The Dissertations Sticky

[bekateen]

Cardoso, Alexandre Rodrigues. 2008. Filogenia da família Aspredinidae adams, 1854 e revisão taxonômica de Bunocephalinae Eigenmann & Eigenmann, 1888 (teleostei: siluriformes: aspredinidae). PhD dissertation, Pontifícia Universidade Católica do Rio Grande do Sul. Programa de Pós-Graduação em Biociências – Zoologia.

Reference: http://meriva.pucrs.br/dspace/handle/10923/5354; complete PDF HERE.

ABSTRACT
With base on the analysis morphological of 153 characteres and 53 taxa of Aspredinidae are proposed the following results: a)

Acanthobunocephalus

and

Bunocephalus

as monophyletic groups and their interrelations resolved b) eight new species of aspredinids, being that five of them already mentioned by Friel (Acanthobunocephalus sp. nov. 1., Acanthobunocephalus sp. nov. 2., Acanthobunocephalus “l” sp. nov., Amaralia sp. nov. and Ernstichthys sp. nov. ) and three discoveries during the development of this study (Acanthobunocephalus sp. nov. 3., Acanthobunocephalus sp. nov. 4 and Bunocephalus sp. nov. ); c) reallocation of some species of Bunocephalus (B. amazonicus, B. bifidus, B. iheringii, B. quadriradiatus, B. rugosus) in Acanthobunocephalus; d) Bunocephalus aloikae as a species valid and not as synonym of Bunocephalus amaurus; e) key for species from Acanthobunocephalus and Bunocephalus; f) a new classification for Aspredinidae; and g) the corroboration of the hypothesis that Aspredinidae is sister to the Asian Sisoroidea (Amblycipitidae, Akysidae, Sisoridae, and Erethistidae) as proposed by de Pinna, Britto and Diogo Vandewalle & Chardon, and not to the Doradoidea, as suggested by Friel and Sullivan, Lundberg & Hardman.

RESUMO
Com base na análise morfológica de 153 caracteres de 53 táxons de Aspredinidae são propostos os seguintes resultados: a) Acanthobunocephalus e Bunocephalus como grupos monofiléticos e com suas inter-relações resolvidas; b) oito espécies novas de aspredinídeos, sendo que cinco delas já mencionadas por Friel (Acanthobunocephalus sp. nov. 1., Acanthobunocephalus sp. nov. 2., Acanthobunocephalus “l” sp. nov., Amaralia sp. nov. e Ernstichthys sp. nov. ) e três descobertas durante o desenvolvimento deste estudo (Acanthobunocephalus sp. nov. 3., Acanthobunocephalus sp. nov. 4 e Bunocephalus sp. nov. ); c) transferência de algumas espécies de Bunocephalus (B. amazonicus, B. bifidus, B. iheringii, B. quadriradiatus e B. rugosus) para Acanthobunocephalus; d) Bunocephalus aloikae como uma espécie válida e não como sinônimo de Bunocephalus amaurus; e) chave para as espécies de Acanthobunocephalus e Bunocephalus; e) uma nova classificação para Aspredinidae; e f) corroboração da hipótese de que Aspredinidae é grupo irmão do clado asiático Sisoroidea (Amblycipitidae, Akysidae, Sisoridae e Erethistidae), como proposto por de Pinna, Britto e Diogo, Vandewalle & Chardon, e não de Doradoidea como sugerido por Friel e Sullivan, Lundberg & Hardman.

This is dated and some conclusions were never validated (e.g., transferring

Pseudobunocephalus

and one species of

Bunocephalus

to

Acanthobunocephalus

), but it has photos of some Bunocephalus not otherwise easily found.

Also, the keys for these fish were extracted and posted here: Cardoso's (2008) key to the genera Bunocephalus, Pseudobunocephalus, and Acanthobunocephalus.

[bekateen]

Turner, D.R. (2017). "Trophic dynamics of flathead catfish in the Missouri River bordering Nebraska." M.S. Thesis, University of Nebraska, 2017. Dissertations & Theses in Natural Resources. 156.

http://digitalcommons.unl.edu/natresdiss/156
Pdf: http://digitalcommons.unl.edu/cgi/viewc ... natresdiss

ABSTRACT

Understanding the trophic dynamics of large, riverine ecosystems is complex and requires knowledge from several inputs and outputs of the ecosystem. Most riverine ecosystems have been altered in some way whether through damming, channelizing, or diverting water. The Missouri River is not immune to these anthropogenic alterations. The river has dams throughout its middle portion and is channelized from Sioux City, Iowa to its confluence with the Mississippi River. Flathead Catfish pylodictus olivarius [sic] are one of the most ecologically harmful introduced species but little research has looked at the influence native populations of Flathead Catfish have on native prey populations where river modification has occurred. I collected Flathead Catfish diet samples and analyzed potential and realized prey caloric content to answer questions on how this abundant, apex predator influences prey populations within their native range. Flathead Catfish had similar diets among three distinct seasons (spring, summer, fall), selected for three fish species (Common Carp, Flathead Catfish, and Shovelnose Sturgeon) and two macroinvertebrate taxa (Ephemeroptera and Plecoptera), and consumed prey resources in similar quantities to introduced populations. The caloric values for prey items varied but selected species did not have highest nor lowest values. Using our diet indices and consumption rates, I estimated that Flathead Catfish consumed on average 175.3 ± 2.1 kcals (dry weight) per individual per day, equivalent to around 220.9 kg of biomass consumed by the entire sample population daily. This research will help researchers better understand the trophic dynamics within the Missouri River ecosystem.

Keyword:

Pylodictis olivaris

[bekateen]

Silva, L.M.D. (2017). "Análises cromossômicas, clássica e molecular, de três espécies de Farlowella Eigenmann & Eigenmann, 1889 (Siluriformes, Loricariidae, Loricariinae)." [75 f.]. Dissertação (Genética, Conservação e Biologia Evolutiva (GCBEv)) - Instituto Nacional de Pesquisas da Amazônia, Manaus.

Silva, L.M.D. (2017). "Classical and molecular chromosomal analyzes of three species of Farlowella Eigenmann & Eigenmann, 1889 (Siluriformes, Loricariidae, Loricariinae)." [75 f.]. Dissertation (Genetics, Conservation and Evolutionary Biology (GCBEv)) - National Research Institute of the Amazon, Manaus.

http://bdtd.inpa.gov.br/handle/tede/2332

RESUMO:

O gênero Farlowella é conhecido como bagre-vara ou peixe-galho, de distribuição restrita aos rios da América do Sul, tendo, na bacia amazônica, grupos de espécies endêmicas. Este gênero é caracterizado por apresentar: corpo coberto por placas ósseas, pedúnculo caudal longo e deprimido, focinho proeminente e ausência de nadadeira adiposa e por causa de sua morfologia peculiar são apreciados como peixes ornamentais. Entretanto, a sistemática de Farlowella permanece confusa e controversa, e tem passado por diferentes agrupamentos ao longo de sua história. Assim, o presente estudo objetivou analisar, por meio da citogenética clássica e molecular, três espécies de Farlowella que ocorrem na bacia do rio Negro, a fim de encontrar possíveis marcadores espécie-específicos ou populacionais, que permitam inferir sobre os mecanismos de sua evolução cromossômica. Foram analisados 28 indivíduos de três espécies de Farlowella de diferentes localidades: F. cf. amazona proveniente das adjacências da cidade de Barcelos-AM, F. oxyrryncha do Igarapé do Sítio Agenor e F. schreitmuelleri do Igarapé Jundiá, ambos localizados no Município de Manaus-AM. As três espécies apresentaram 2n=58 cromossomos e número fundamental 110, 112 e 116 braços, respectivamente. Quanto à heterocromatina constitutiva, as três espécies exibiram blocos na região centromérica, bem como algumas arcações biteloméricas e somente F. oxyrryncha e F. schreitmuelleri apresentaram marcações intersticiais. Ainda, o padrão de banda C observado no par 27 de F. oxyrryncha caracteriza um sistema de cromossomos sexuais do tipo XX/XY. O par cromossômico nucleolar parece ser homeólogo entre as espécies. A sonda de DNAr 5S foi um marcador espécie-específico. A FISH com sonda telomérica detectou sequências teloméricas intersticiais (ITS) em F. oxyrryncha e em F. schreitmuelleri e estas foram coincidentes com heterocromatina. Em F. oxyrryncha a ITS foi polimórfica, sendo observadas quatro variações. A partir dos dados obtidos foi possível sugerir que os rearranjos cromossômicos, envolvidos na evolução cariotípica desse gênero e na diferenciação de cromossomos sexuais são não Robertsonianos e que as diferenças interespecíficas e populacionais podem sugerir a presença de complexos de espécies nesse gênero.

ABSTRACT

The genus Farlowella is known as catfish or branchfish, of distribution restricted to the rivers of South America, having, in the Amazon basin, groups of endemic species. This genus is characterized by presenting: body covered by bony plates, long and depressed caudal peduncle; prominent snout and absence of adipose fin and because of their peculiar morphology are sold as ornamental fish. However, Farlowella's systematics remains confused and controversial, and has gone through different groupings throughout its history. Thus, the present study aimed to characterize, through classical and molecular cytogenetic analyzes, three Farlowella species that occur in Negro River basin, in order to find possible species-specific markers or population-based markers that allow inferring on the mechanisms of its chromosome evolution. We analyzed 28 individuals of three Farlowella species from different localities: F. cf. amazona from the vicinity of the city of Barcelos-AM, F. oxyrryncha of the Igarapé of Agenor Site and F. schreitmuelleri of Igarapé Jundiá, both located in the Municipality of Manaus-AM. The three species presented 2n = 58 chromosomes and fundamental number 110, 112 and 116 arms. As for constitutive heterochromatin, the three species exhibited blocks in centromeric region and adjacencies, as well as some bitelomeric markers and only F. oxyrryncha and F. schreitmuelleri showed interstitial markings. Furthermore, the C-band pattern observed in pair 27 of F. oxyrryncha appears to characterize a sex chromosome system of type XX/XY. The nucleolar chromosomal pair appears to be homeologous between species. The 5S rDNA probe was a species-specific marker. FISH with telomeric probe detected interstitial telomeric sequences (ITS) in F. oxyrryncha and F. schreitmuelleri and these were matched with heterochromatin. In F. oxyrryncha ITSs was polymorphic, with four variations observed. From the data obtained it was possible to suggest that the chromosomal rearrangements involved in the karyotype evolution of this genus and in the differentiation of sex chromosomes are non Robertsonian rearrangements, and that interspecific and population differences may suggest the presence of species complexes in this genus.

Species analyzed:

• Farlowella cf. amazonum
• Farlowella oxyrryncha
• Farlowella schreitmuelleri

[bekateen]

Andrade, Breno Neves de. 2017. Systematics of Neoplecostomus Eigenmann & Eigenmann, 1888 (Siluriformes: Loricariidae: Neoplecostominae). Ph.D. Thesis, São Paulo State University, S. J. Rio Preto Campus, Brazil.

Andrade, Breno Neves de. 2017. Sistemática de Neoplecostomus Eigenmann & Eigenmann, 1888 (Siluriformes: Loricariidae: Neoplecostominae). Ph.D. Tese, Universidade Estadual Paulista "Júlio de Mesquita Filho", Campus de São José do Rio Preto, Brazil.

LINK: https://repositorio.unesp.br/handle/114 ... ?show=full
Partial PDF: Here
Full (maybe) PDF (link didn't work for me): Here

ABSTRACT

Neoplecostomus

currently includes sixteen valid species, with nine of those described in the last nine years. The genus is distributed at Paraná, Doce, São Francisco, Paraíba do Sul, Ribeira de Iguape, Iguaçu river basins, and other coastal and independent basins in southern and southeastern of Brazil. Moreover, there are evidences of new species for most of these basins and others basins where the genus has not been registered yet. According to the phylogenetic relationships proposed for Neoplecostominae sensu Pereira (2008) and based on morphological data, Neoplecostomus is monophyletic, contrary to the hypothesis based on molecular data, which indicates a non-monophyletic Neoplecostomus. In this context, the aims of the present study were: (1) to perform a phylogenetic analysis and a taxonomic revision of Neoplecostomus genus; (2) to evaluate the specific composition and the monophyly of the genus; and (3) to evaluate the phylogenetic relationship within the genus and among the genus and other Neoplecostominae genera. Phylogenetic analysis was performed with 273 characters from 62 terminal taxa, including species from Astroblepidae, Delturinae, Loricariinae, Hypostominae, Hypoptopomatinae and Neoplecostominae. The analysis produced only one more parsimonious tree that corroborated Neoplecostominae monophyly. Neoplecostominae is composed only by ((

Pareiorhina hyptiorhachis

+ (

Pareiorhina carrancas

+ (

Pareiorhina pelicicei

+ (

Pareiorhina rosai

+

Pareiorhina brachyrhyncha

)))) + (

Pareiorhina rudolphi

+ (

Pareiorhaphis

+ (

Isbrueckerichthys

+ Neoplecostomus)))))). Supported by 34 synapomorphies, Neoplecostomus was also monophyletic in our analysis. The genus showed seven exclusive synapomorphies: a (1) ventral dense plate shield surpassing the transverse line that passes through the base of the pelvic-fin insertions; (2) absence of smaller platelets between a dense plate shield and pectoral-fin insertions; (3) pectoral-fin spine distinctly curved and forming a wide and conspicuous arch; (4) distal portion of the lateropterygium distinctly spatulate; (5) conspicuous rows of enlarged and transversely flattened papillae just posterior to the dentary teeth; (6) two conspicuous rows of enlarged and transversely flattened papillae just posterior to the dentary teeth and (7) conspicuous rows of enlarged and transversely flattened papillae just posterior to the dentary teeth, with rounded format. Additionally, the intra-relationships among Neoplecostomus species were: N. bandeirante + (((N. langeanii + N. jaguari) + ((N. corumba + N. paranensis) + (N. botucatu + (N. yapo + N. selenae)))) + ((N. sp. n. Iguaçu + N. sp. n. Delfim) + (N. sp. n. Piquiri + (N. doceensis + (N. sp. n. Doce + (N. sp. n. São Francisco + N. sp. n. Araguari))))) + (N. ribeirensis + (N. sp. n. Itapemirim + ((N. franciscoensis + N. espiritosantensis) + (N. microps + (N. paraty + N. granosus)))))). As a result of the taxonomic revision, we presented a redescription of the genus and of fifteen of the sixteen valid species, with emphasis on the rediscovery of

Neoplecostomus granosus

and the possible type locality, one species that for several years has been identified as a synonymous of N. microps. Furthermore, seven new species were proposed for the genus and

Neoplecostomus variipictus

was synonymized with N. microps.

• Keywords: Phylogeny, Taxonomy, Shells, Morphology, Brazilian Crystalline Shield,
  Fresh water.

RESUMO

Neoplecostomus

é composto atualmente por dezesseis espécies válidas, com nove dessas espécies descritas nos últimos nove anos. O gênero distribui-se pelas bacias dos rios: Paraná, Doce, São Francisco, Paraíba do Sul, Ribeira de Iguape, Iguaçu e outras bacias litorâneas e independentes do sul e sudeste brasileiro, com indícios de espécies novas para a maioria dessas bacias e outras bacias ainda não registradas. De acordo com as relações filogenéticas propostas para Neoplecostominae, por Pereira (2008), com dados morfológicos, Neoplecostomus é monofilético, divergindo das hipóteses baseadas em dados moleculares mais recentes, que aponta Neoplecostomus não monofilético. Desse modo, os objetivos do presente estudo foram: (1) realizar uma análise filogenética e revisar taxonomicamente Neoplecostomus; (2) avaliar a composição e monofiletismo do gênero e, (3) avaliar as relações filogenéticas de suas espécies e delas com os demais Neoplecostominae. A análise filogenética foi realizada com base em 273 caracteres, investigados em 62 táxons terminais, com membros pertencentes à Astroblepidae, Delturinae, Loricariinae, Hypostominae, Hypoptopomatinae e Neoplecostominae. Os resultados obtidos, a partir de uma única árvore mais parcimoniosa, corroboram Neoplecostominae monofilético, formado apenas por ((

Pareiorhina hyptiorhachis

+ (

Pareiorhina carrancas

+ (

Pareiorhina pelicicei

+ (

Pareiorhina rosai

+

Pareiorhina brachyrhyncha

)))) + (

Pareiorhina rudolphi

+ (

Pareiorhaphis

+ (

Isbrueckerichthys

+ Neoplecostomus)))))). Neoplecostomus também resulta monofilético em nossa análise, suportado por 34 sinapomorfias, sendo sete sinapomorfias exclusivas: (1) escudo ventral, pentagonal ou hexagonal, formado por pequenas placas, ultrapassando a linha transversal que passa pela base do raio indiviso da nadadeira pélvica; (2) placas menores entre o escudo ventral de placas (pentagonal ou hexagonal) e a inserção do raio indiviso da nadadeira peitoral ausentes; (3) perfil dorsal do raio não ramificado da nadadeira peitoral com curvatura acentuada; (4) porção distal do lateropterígio claramente espatulado; (5) papilas conspícuas posteriores ao dentário presentes; (6) duas fileiras de papilas conspícuas posterior ao dentário e, (7) papilas conspícuas após os dentes do dentário arredondadas. Adicionalmente, a seguinte intra-relação de Neoplecostomus foi encontrada: N. bandeirante + (((N. langeanii + N. jaguari) + ((N. corumba + N. paranensis) + (N. botucatu + (N. yapo + N. selenae)))) + ((N. sp. n. Iguaçu + N. sp. n. Delfim) + (N. sp. n. Piquiri + (N. doceensis + (N. sp. n. Doce + (N. sp. n. São Francisco + N. sp. n. Araguari))))) + (N. ribeirensis + (N. sp. n. Itapemirim + ((N. franciscoensis + N. espiritosantensis) + (N. microps + (N. paraty + N. granosus)))))). Apresenta-se também o resultado da revisão taxonômica, com a redescrição do gênero e de quinze das dezesseis espécies válidas, com destaque para redescoberta de

Neoplecostomus granosus

e sua possível localidade tipo, espécie que há vários anos acreditava-se ser sinônimo de

Neoplecostomus microps

. Ainda, sete espécies novas são propostas para o gênero e

Neoplecostomus variipictus

é sinonimizado com N. microps.

• Palavras-chave: Filogenia, Taxonomia, Cascudos, Morfologia, Escudo Cristalino Brasileiro,
  Água doce.

[bekateen]

This is an older dissertation, but it should have been listed here when it was released:

Vera-Alcaraz, H.S. 2013. Phylogenetic systematics of armored catfishes of the family Callichthyidae (Siluriformes, Loricariodea). Ph.D. Thesis, Pontifícia Universidade Católica Do Rio Grande Do Sul, Brazil.

Vera-Alcaraz, H.S. 2013. Relações filogenéticas das espécies da família Callichthyidae (Ostariophysi, Siluriformes). Ph.D. Tese, Pontifícia Universidade Católica Do Rio Grande Do Sul, Brazil.

ABSTRACT

The phylogeny of the family Callichthyidae (Siluriformes) was investigated performing a Cladistic parsimony analysis under a Total Evidence approach. Characters explored are mainly based in osteology and molecular data of nuclear and mitochondrial genes. The ingroup included 131 terminals representing 111 species, the outgroup included 13 terminals representing 13 species including

Copionodon

as the rooting taxa. The phylogenetic analysis resulted in 89 most parsimonious trees which are summarized in a strict consensus cladogram; a new phylogenetic classification and the discussion of this paper are addressed based in this topology. The Total Evidence phylogenetic analysis corroborated the monophyly of the family Callichthyidae, subfamilies Callichthyinae and Corydoradinae, genera

Callichthys

,

Dianema

,

Lepthoplosternum

,

Megalechis

, and

Scleromystax

. However, the genera

Aspidoras

,

Corydoras

, and

Hoplosternum

are recovered nonmonophyletic. To reconcile this situation, a revalidation of the genera

Hoplisoma

and

Gastrodermus

is proposed to accommodate most species currently recognized in Corydoras.

Aspidoras virgulatus

and

Corydoras lacerdai

are transferred to Scleromystax to conceive their currently containing genera monophyletic. On the other hand, Hoplosternum is recovered paraphyletic. However, it was decided to hold making taxonomic changes at this moment until molecular dataset is completed for this genus, which is referred temporarily as “Hoplosternum”. Synapomorphies for each clade recovered and ranked in the phylogenetic classification are reported here, emphasizing their morphological diagnoses. Interrelationships between species and clades are discussed and compared with previous taxonomic and phylogenetic hypotheses. In addition, the taxonomy of

Hoplisoma nattereri

was reviewed in order to elucidate its synonymy and investigate the presence of cryptic diversity under this name.

Hoplisoma nattereri

and H. triseriatus are considered valid species. Geographic distribution for each species is also reported.

Corydoras juquiaae

is removed from the synonymy of Hoplisoma nattereri and transferred to

Scleromystax juquiaae

, new combination. Scleromystax prionotos is considered a junior synonym of S. juquiaae. All these species are illustrated in this paper. In addition, the original figure of S. juquiaae prepared but never published by Rudolph von Ihering is reproduced here. Phylogenetic relationships of Hoplisoma nattereri and H. triseriatus are discussed and also the morphometric and genetic distance of some of the populations sampled.

RESUMO

A filogenia da família Callichthyidae (Siluriformes) foi estudada realizando uma análise de Parcimônia Cladística sob uma abordagem de Evidência Total. Caracteres explorados foram principalmente baseados em osteologia e dados moleculares de genes nucleares e mitocondriais. O grupo interno incluiu 131 terminais representando 111 espécies; o grupo externo incluiu 13 terminais representando 13 espécies e incluindo

Copionodon

como o terminal de enraizamento da topologia. A análise filogenética resultou em 89 árvores mais parcimoniosas que foram resumidas em um cladograma de consenso estrito; com base nessa topologia, se propõe e discute uma nova classificação filogenética para Callichthyidae. A análise filogenética de Evidência Total corroborou o monofiletismo da família Callichthyidae, subfamílias Callichthyinae e Corydoradinae, gêneros

Callichthys

,

Dianema

,

Lepthoplosternum

,

Megalechis

e

Scleromystax

. No entanto, os gêneros

Aspidoras

,

Corydoras

e

Hoplosternum

foram recuperados nãomonofiléticos. Para conciliar esta situação, se propõe a revalidação dos gêneros

Hoplisoma

e

Gastrodermus

para acomodar a maioria das espécies atualmente reconhecidas em Corydoras.

Aspidoras virgulatus

e

Corydoras lacerdai

foram transferidas para Scleromystax e assim conceber esses gêneros como monofiléticos. Por outro lado, as espécies de Hoplosternum foram recuperadas como parafiléticas. No entanto, decidiu-se não fazer mudanças taxonômicas no momento até concluir a coleta de dados moleculares para este grupo, o qual é reconhecido temporariamente como “Hoplosternum”. Sinapomorfias para cada clado recuperado e proposto na classificação filogenética são aqui mostrados, enfatizando seus caracteres morfológicos diagnósticos. Inter-relações entre as espécies e clados são discutidas e comparadas com estudos taxonômicos e hipóteses filogenéticas anteriores. Adicionalmente, a taxonomia de

Hoplisoma nattereri

foi revisada a fim de elucidar sua sinonímia e investigar a presença de diversidade críptica sob este nome. Hoplisoma nattereri e H. triseriatus são consideradas espécies válidas. A distribuição geográfica para cada espécie é reportada.

Corydoras juquiaae

é removida da sinonímia de Hoplisoma nattereri e transferida para Scleromystax juquiaae, nova combinação.

Scleromystax prionotos

é considerada um sinônimo júnior de S. juquiaae. Todas estas espécies são ilustradas neste artigo. Também, a figura original de Corydoras juquiaae preparada, mas nunca publicada, por Rudolph von Ihering é aqui reproduzida. As relações filogenéticas de Hoplisoma nattereri e H. triseriatus foram discutidas como assim a sua morfometría e a distância genética de algumas das populações amostradas.

[bekateen]

Santos, M. F. D. (2017). Phylogenetic systematics and chromosome evolution in Amazonian species of Aspredinidae (Ostariophysi, Siluriformes). Ph.D. Thesis (Genetics, Conservation and Evolutionary Biology (GCBEv)) - National Research Institute of the Amazon, Manaus.

Santos, M. F. D. (2017). Sistemática filogenética e evolução cromossômica em espécies amazônicas de Aspredinidae (Ostariophysi, Siluriformes). Ph.D. Tese (Genética, Conservação e Biologia Evolutiva (GCBEv)) - Instituto Nacional de Pesquisas da Amazônia, Manaus.

Link: http://bdtd.inpa.gov.br/handle/tede/2451

ABSTRACT
The Aspredinidae family, order Siluriformes, is a group of Neotropical fishes, popularly known as “banjo catfishes” or “rabeca”. It is strictly distributed in South America, and within the Amazon River basin, there are endemic species groups. In the present study, cytogenetic and molecular analysis were performed with species of this family, aiming at understanding the evolutionary processes involved in the diversification of these small catfishes, in order to infer their taxonomic status. Some inedited chromosomal characterizations were presented, of the species

Amaralia hypsiura

, Bunocephalus cf. aloikae, B. amaurus, B. coracoideus, B. aff coracoideus, B. verrucosus and

Platystacus cotylephorus

. The chromosomal data, with the 5S rDNA mapping and the constitutive heterochromatin distribution, revealed a new sex chromosomes system of the X 1 X 1 X 2 X 2 /X 1 Y 1 X 2 Y 2 type in a B. coracoideus population. The karyotype characterization of P. cotylephorus revealed a second event of XX/XO sex system for Siluriformes. The analysis of a phylogram with four

Bunocephalus coracoideus

populations, based on one mitogenome region, revealed some clades with genetic diversity, suggesting the existence of well supported Evolutionary Significant Units, building a species complex, under allopatric and sympatric speciation processes. Yet, the chromosomal data allowed noticing a trend on the reduction of the diploid number during the chromosomal evolution of the family, in relation to the ancestral karyotype of the Siluriformes, although keeping a karyotype with most of the chromosomes being two-armed ones. Later on, by means of chromosomal rearrangements of the type pericentric inversions and fission, the diploid number of some species increased and the karyotype morphology changed to single-armed chromosomes, a synapomorphy for the family. The karyotype diversity, both on the diploid number and the chromosome morphology in Aspredinidae, it very similar to the ones found in families from the Asiatic clade Sisoroidea (Amblycipitidae, Akysidae, Sisoridae and Erethistidae), suggesting that these families went under the different selective pressures for the karyotype building or a common natural history. Thus, it corroborates the propositions of Aspredinidae and Sisoroidea as sister-groups, suggested by Ferraris (1989), de Pinna (1998), Britto (2002), Diogo et al. (2004) and Cardoso (2000).

• Key words: Banjo fish, Chromosomes

RESUMO
A família Aspredinidae, ordem Siluriformes, é composta por um grupo de peixes neotropicais, popularmente conhecidos como bagres banjo ou rabeca. Possui distribuição restrita à América do Sul, tendo na bacia amazônica, importantes grupos de espécies endêmicas. No presente trabalho, foram realizadas análises citogenéticas e moleculares em espécies desta família, com objetivo de compreender os processos evolutivos envolvidos na diversificação destes pequenos bagres, a fim de inferir no status taxonômico. Foram disponibilizadas caracterizações cromossômicas inéditas de

Amaralia hypsiura

, Bunocephalus cf. aloikae, B. amaurus, B. coracoideus, B. aff coracoideus, B. verrucosus e

Platystacus cotylephorus

. Os dados cromossômicos, com mapeamento de DNAr 5S e distribuição da heterocromatina constitutiva revelaram um sistema de cromossomos sexuais inédito do tipo X 1 X 1 X 2 X 2 /X 1 Y 1 X 2 Y 2 em uma população de B. coracoideus. E caracterização cariotípica de P. cotylephorus revelou um segundo caso em Siluriformes de sistema sexual XX/XO. A análise de um filograma com quatro populações de

Bunocephalus coracoideus

, com base em uma região do mitogenoma, revelou clados com diversidade genética, que corroboraram os dados de distribuição geográfica e variação cariotípica, sugerindo a existência de Unidades Evolutivas Significativas bem suportadas, formando um complexo de espécies, em processo de especiação alopátrica e simpátrica. Ainda, os dados cromossômicos permitiram a percepção de uma tendência à redução do número diploide na evolução cromossômica da família em relação ao cariótipo ancestral dos Siluriformes, conservando um cariótipo com maioria de cromossomos de dois braços. E, posteriormente, por rearranjos cromossômicos do tipo inversões pericêntricas e fissões, o número diploide de algumas espécies teria aumentado e a morfologia cariotípica se modificado para cromossomos de um braço, sendo este uma sinapomorfia na família. A
diversidade cariotípica, tanto no número diploide como na morfologia dos cromossomos em Aspredinidae é muito parecida às encontradas nas famílias do clado asiático Sisoroidea (Amblycipitidae, Akysidae, Sisoridae e Erethistidae), sugerindo que essas famílias sofreram as diferentes pressões seletivas para formação dos cariótipos ou uma história natural em comum. Assim, corroborando com a proposta de Aspredinidae e Sisoroidea serem grupos-irmãos, sugerida por Ferraris (1989), de Pinna (1998), Britto (2002), Diogo et al. (2004) e Cardoso (2010).

• Palavras-chave: Peixe-banjo, Cromossomos

[bekateen]

Rivera Rivera, C.J. (2017). Phylogeny of denticulate catfish (Loricarioidei: Siluriformes) and their use as a new model to understand the evolution and development of dental tissue in new areas of the vertebrate body. Doctoral dissertation, University of Geneva. https://archive-ouverte.unige.ch/unige:101381
http://dx.doi.org/10.13097/archive-ouverte/unige:101381
Not publicly available until until 2019-07-15

ABSTRACT
Dental structures originally emerged as components of the exoskeleton of ancestral vertebrates. Throughout evolution, these structures started being built inside the oral cavity, allowing these ancestral vertebrates to switch to a more predatory lifestyle and opening a vast diversity of new ecological niches. However, to date, the evolutionary and developmental processes by which dental structures can be built in new areas of the body plan are not clear. One of the main limitations for investigating this question is the lack of informative model organisms that show a clear gain of dental structures in new areas of the body. In this study, I focus my studies on catfish (Teleostei: Silurifomes): a highly diverse group of fish that contains a lineage of denticulate catfish (Loricarioidei) in which dental structures presumably emerged de novo on extra-oral body surfaces. I use the Loricarioidei to study the evolutionary and developmental mechanisms through which dentition can be built in new areas of the vertebrate body plan. Because this lineage has never been studied in the context of dental evolution, I must take a multidisciplinary approach at this question to have a broad perspective of the factors related to the gain of dental structures in the loricarioid body. In this work I integrate information that I recovered through studies in the fields of molecular phylogenetics, morphology, evolutionary biology and developmental biology. I begin by determining the phylogenetic landscape in which these denticles emerged, and start by placing the Loricarioidei within the catfish phylogeny. However, the fast molecular evolution of this group and the general diversity of evolutionary rates among catfish species raise methodological challenges for inferring this phylogeny correctly. I address these challenges and propose two new methods, LS³ and LS⁴, to improve any phylogeny inference in which extreme heterogeneous evolutionary rates may be a source of bias. I apply LS⁴ as implemented in a software I produced for this work, LSX, on a new molecular dataset to address the position of the Loricarioidei, and I am able to place this lineage nested within Siluriformes, among groups of catfish that have a naked skin. These results confirm that dental structures indeed emerged de novo in the extra-oral regions of loricarioids. I then ask if the evolutionary emergence of the loricarioid denticles was linked to the formation of other bony elements observed in this lineage, such as dermal bony plates. Through ancestral state reconstruction, I find that the emergence of loricarioid denticles was not linked in evolution to the emergence of dermal bony plates, but that an underlying superficial bone is likely essential for the formation of these dental structures. In the final section of this work I enter into the developmental mechanisms through which these de novo dental structures are built. I use the species Ancistrus triradiatus, which is the new model loricarioid catfish species developed in the laboratory of Juan Montoya-Burgos. Through in situ hybridization and immunostaining studies, I find that loricarioid denticles, despite being an independent emergence of dental structures in new body areas, are produced by deploying the same developmental genetic program that produces oral teeth in other vertebrates. This indicates that dental structures found inside and outside the oral cavity in this loricarioid model species are homologous. In view of these results I conclude that it is possible for vertebrates to gain dental structures in new areas of the body through the cooption of the oral tooth developmental program.

• Keywords: Phylogenetics, Systematics, Long branch attraction, R, Bioinformatics, Siluriformes, Diplomystidae, Loricarioidei, Armored catfish, Denticles, Trunk dental tissue, Denticle development, Odontodes

[bekateen]

Well done Luiz! Congratulations!
http://nou-rau.uem.br/nou-rau/document/ ... s000227650

EDIT: As of 11-October-2018, the entire dissertation is now available here in pdf format: https://www.oceandocs.org/bitstream/han ... sequence=1

Luiz Fernando Caserta Tencatt. (2018). Os cascudos Aspidoras Ihering, 1907 (Siluriformes: Callichthyidae): uma revisão taxonômica, com a descrição de uma espécie nova. Tese (doutorado em Ecologia de Ambientes Aquáticos Continentais), Universidade Estadual de Maringá. Departamento de Biologia.

Luiz Fernando Caserta Tencatt. (2018). The Aspidoras Ihering, 1907 (Siluriformes: Callichthyidae) armored catfishes: a taxonomic review, with description of a new species. Thesis (Doctorate in Ecology of Continental Aquatic Environments), State University of Maringá. Department of Biology.

RESUMO:

Aspidoras

foi descrito por Ihering como um gênero monotípico para abrigar A. rochai. Atualmente, o gênero inclui 24 espécies válidas, sendo relativamente bem Distribuído ao longo do território brasileiro, ocorrendo de São Paulo, seu registro mais ao sul, até o Ceará. Após a primeira revisão taxonômica fornecida por Nijssen & Isbrücker 40 anos atrás, nenhum trabalho extensivo com o objetivo de elucidar a taxonomia de Aspidoras foi conduzido. Uma revisão taxonômica abrangente foi realizada para o reconhecimento claro do gênero através de uma nova diagnose, que inclui uma possível característica exclusiva, a presença de pequenas expansões laminares na base dos raios ramificados da nadadeira peitoral. Considerando a nova diagnose e os dados filogenéticos disponíveis atualmente, A. pauciradiatus e A. virgulatus foram excluídas de Aspidoras, sendo transferidas para Corydoras e Scleromystax, respectivamente. A respeito das demais espécies, algumas sinonímias novas são propostas: A. eurycephalus e A. taurus com A. albater; A. menezesi e A. spilotus com A. raimundi; e A. microgaleus e A. marianae com A. poecilus. Adicionalmente, uma espécie nova das bacias dos rios Araguaia e Paraguai no estado do Mato Grosso é descrita. A espécie nova pode ser distinguida de suas congeneres por apresentar a combinação de duas características: parapófise do complexo de vértebras bem desenvolvido, e porção anterior do infraorbital 1 com expansão laminar pouco desenvolvida, ligeiramente ultrapassando a margem posterior da cápsula nasal. Assim, o número de espécies válidas em Aspidoras foi reduzido de 24 para 17. Redescrições para A. albater, A. belenos, A. depinnai, A. fuscoguttatus, A. lakoi, A. maculosus, A. poecilus, A. psammatides, A. raimundi e A. velites foram fornecidas. Uma chave de identificação englobando as espécies de Aspidoras, com exceção de A. carvalhoi, também é fornecida.

ABSTRACT:

Aspidoras

was described by Ihering as a monotypic genus to harbour A. rochai. Currently, the genus comprises 24 valid species, and is relatively well distributed across the Brazilian territory, occurring from São Paulo, its southernmost record, to Ceará. After its first taxonomic review provided by Nijssen & Isbrücker 40 years ago, no extensive work aiming to elucidate the taxonomy of Aspidoras was conducted. Therefore, a comprehensive taxonomic review was carried out, allowing the clear recognition of the genus through a new diagnosis that includes a possible exclusive feature, the presence of small laminar expansions on base of the pectoral-fin branched rays. Considering the new diagnosis plus the currently available phylogenetic data, A. pauciradiatus and A. virgulatus are herein excluded from Aspidoras, being transferred to Corydoras and Scleromystax, respectively. Regarding the remaining species, some new synonymies are proposed: A. eurycephalus and A. taurus with A. albater; A. menezesi and A. spilotus with A. raimundi; and A. microgaleus and A. marianae with A. poecilus. Additionally, a new species from the rivers Araguaia and Paraguay basins in Mato Grosso State is described. The new species can be distinguished from its congeners by having the combination of two features: parapophysis of the complex vertebra well developed, and anterior portion of infraorbital 1 with poorly-developed laminar expansion, slightly surpassing posterior margin of nasal capsule. Thereby, the number of valid species within Aspidoras was reduced from 24 to 17. Redescriptions for A. albater, A. belenos, A. depinnai, A. fuscoguttatus, A. lakoi, A. maculosus, A. poecilus, A. psammatides, A. raimundi and A. velites are provided. An identification key encompassing the species of Aspidoras, with exception of A. carvalhoi, is also provided.

[bekateen]

Thereza, Mariana Ribeiro. (2018). Identification guide for siluriform fish (Teleostei: Ostariophysi) from the Rio Grande basin, upper Paraná river. Masters Dissertation, Universidade Estadual Paulista (UNESP), São José do Rio Preto Campus.

Source: http://hdl.handle.net/11449/153403
PDF: https://repositorio.unesp.br/bitstream/ ... sAllowed=y

Thereza, Mariana Ribeiro. (2018). Guia de identificação dos peixes Siluriformes (Teleostei: Ostariophysi) da bacia do rio Grande, alto rio Paraná. Dissertação Mestrado, Universidade Estadual Paulista (UNESP), Campus de São José do Rio Preto.

ABSTRACT:
The Grande River basin belongs to Alto Paraná River, which is the most studied portion of Paraná River basin regarding the icthyofauna. However, this does not indicates that the basin was fully sampled or inventoried. In addition, the researchers do not contain tools to identify the species. The Siluriformes, one of the six orders that is found in the Grande River basin, shows great representativeness with more than 30% (it may reach 35%) of the total of fish species. Our aim was to elaborate an identification guide composed by one identification key, diagnosis and photographic records of each Siluriformes species from the Grande River basin. We found 86 valid species, one new genera and two new species. The species belong to 11 families, whereas Loricariidae was the most diverse one with 41% of the total species richness. The revised material of Siluriformes from the Grande River basin of the fish collection of the Department of Zoology and Botany was mainly from the São Paulo State drainage and few records from Minas Gerais State drainages. The accumulation curve showed an exponential pattern, indicating that despite extensively studied, it is possible that Grande River basin still has new species to be found and described by science.

• Key words: taxonomy, catfishes, identification key

RESUMO:
A bacia do rio Grande pertence a porção mais estudada com relação a ictiofauna da drenagem do rio Paraná, a bacia do Alto rio Paraná. Entretanto, isso não significa que a bacia foi amostrada e inventariada em sua totalidade. Além disso, nenhuma das pesquisas apresenta ferramentas adequadas para a identificação das espécies. Os Siluriformes, uma das seis ordens que compõem a ictiofauna da bacia do rio Grande, apresentam grande representatividade dentro da bacia, com cerca de 30% (podendo chegar a 35%) das espécies de peixes. Sendo assim, o objetivo deste trabalho foi a elaboração de um guia de identificação composto por chave de identificação, diagnoses e registro fotográficos das espécies de Siluriformes da bacia do rio Grande. Foram listadas 86 espécies válidas, um novo gênero e duas novas espécies para a bacia. As espécies pertencem à onze famílias, sendo Loricariidae a mais diversa, com 41% da riqueza de espécies. O material revisado de Siluriformes da bacia do rio Grande da coleção do Departamento de Zoologia de Botânica da UNESP de São José do Rio Preto foi amostrado principalmente nas drenagens do estado de São Paulo e em menor proporção nas drenagens de Minas Gerais. A curva de acumulação de espécies apresentou crescimento exponencial, indicando que apesar de extensivamente estudada, é possível que a bacia do rio Grande ainda apresente novas espécies a serem encontradas e descritas pela ciência.

• Palavras-chave: Taxonomia, Cascudos, Bagres, Chave de identificação

[bekateen]

Motta, Veronica de Barros Slobodian. (2018). Taxonomic revision of Pimelodella Eigenmann & Eigenmann, 1888 (Siluriformes: Heptapteridae). Doctoral Thesis, Museu de Zoologia, University of São Paulo, São Paulo. Retrieved 2018-04-18, from http://www.teses.usp.br/teses/disponive ... 18-142608/
INCOMPLETE PDF: http://www.teses.usp.br/teses/disponive ... FICADA.pdf

Motta, Veronica de Barros Slobodian. (2018). Revisão taxonômica de Pimelodella Eigenmann & Eigenmann, 1888 (Siluriformes: Heptapteridae): uma proposta integrativa para a delimitação de espécies com estratégias multidisciplinares. Tese de Doutorado - Programa de Pós-Graduação em Sistemática, Taxonomia e Biodiversidade, Museu de Zoologia, Universidade de São Paulo, 2017.

ABSTRACT
Primary taxonomic research in neotropical ichthyology still suffers from limited integration between morphological and molecular tools, despite major recent advancements in both fields. Such tools, if used in an integrative manner, could help in solving long-standing taxonomic problems. The genus

Pimelodella

Eigenmann & Eigenmann, 1888 is a perfect case for an integrative and multidisciplinary approach in taxonomy. Pimelodella is a genus of the Heptapteridae broadly distributed throughout trans- and cis-Andean South America, and one of the main components of Neotropical Ichthyofauna. Nowadays is the most species-rich genus of the family, with 79 valid species. However, the validity and delimitation of those species is extremely problematic, due their broad geographic distribution, conserved morphology, and ancient and imprecise descriptions. Pimelodella is undoubtedly one of the most severe taxonomic bottlenecks in neotropical ichthyology. This project presents a taxonomic revision of Pimelodella using an integrative morphological-molecular approach. The traditional taxonomic revision covers the genus in its entirety, with all the components of this kind of study. All types were examined, and the number of valid species herein recognized was reduced to 55 species, for which full descriptions are presented. The molecular taxonomy was done for a circumscribed subset of the genus, with representation enough to understand the molecular divergences and compare them with the traditional taxonomy results, allowing an evaluation of the results of the revision.

• Key words: Comparative Anatomy, Integrative taxonomy, Neotropical Ichthyofauna, Species Trees.

RESUMO
A pesquisa taxonômica primária ainda apresenta pouca integração entre as ferramentas morfológicas e moleculares para o estudo de peixes neotropicais, apesar de grandes avanços recentes em ambos os campos. Tais ferramentas, se usadas de maneira integrativa, poderiam solucionar grupos reconhecidos por representarem problemas taxonômicos renitentes. O gênero

Pimelodella

Eigenmann & Eigenmann, 1888 se enquadra como um ótimo caso para a aplicação de uma estratégia integrativa e multidisciplinar. Pimelodella é um gênero da família Heptapteridae, distribuído amplamente por drenagens sul-americanas trans- e cis-andinas e compreende um dos principais componentes da ictiofauna neotropical. Atualmente é reconhecido como o maior gênero da família, com 79 espécies válidas descritas. Entretanto, a validade e delimitação dessas espécies é problemática, devido à elevada diversidade do gênero, aliada à ampla distribuição, morfologia conservada e descrições antigas e imprecisas. Trata-se de um dos grandes gargalos taxonômicos na sistemática e taxonomia de peixes neotropicais. Este projeto apresenta uma revisão taxonômica de Pimelodella utilizando uma abordagem integrativa morfológica-molecular. A revisão taxonômica clássica cobre a integridade da diversidade do gênero, com todos os componentes deste tipo de estudo. Todos os tipos foram examinados, e o número de espécies validas é aqui reduzido para 55 espécies, para as quais descrições completas são apresentadas. A parte molecular foi realizada em um subgrupo delimitado, com diversidade suficiente para que as estimativas de divergência molecular pudessem ser comparadas aos resultados da revisão morfológica, fornecendo um modelo de avaliação para o restante da revisão.

• Anatomia Comparada, Árvores de espécies, Ictiofauna Neotropical, Taxonomia integrativa

[bekateen]

Slusher, Monique Renee. (2018). "Morphological Correlates and Behavioral Functions of Sound Production in Loricariid Catfish, With a Focus on Pterygoplichthys pardalis (Castelnau, 1855)". Dissertations and Theses. Paper 4155.
https://pdxscholar.library.pdx.edu/open ... _etds/4155
http://dx.doi.org/10.15760/etd.6043
Persistent Identifier: http://archives.pdx.edu/ds/psu/23894

Abstract
The Neotropical catfish

Pterygoplichthys pardalis

produces a harsh stridulation sound upon manual capture. This stridulation sound is made on the abduction of the pectoral fin spine, and is accomplished by friction of a ridged dorsal condyle against a rough spinal fossa of the cleithrum in the pectoral girdle. The sound produced has an average frequency of 121 Hz, and is used with other anti-predator adaptations such as bony subdermal armor and defensive fin-spreading. Pterygoplichthys pardalis does not display behavioral modification in response to conspecific stridulation sound, and therefore it is likely that stridulation sound in P. pardalis is being used as a predator deterrent.

[bekateen]

Pacaya Flores, F. (2018). Reproduction in captivity of the "brown carachama" Hypostomus hemicochliodon (loricariidae), in the "Carlos Miguel Castañeda Ruíz" research center. IIAP. San Martín.

Pacaya Flores, F. (2018). Reproducción en cautiverio de la “carachama parda” Hypostomus hemicochliodon (loricariidae), en el centro de investigaciones “Carlos Miguel Castañeda Ruíz”. IIAP. San Martín.

http://renati.sunedu.gob.pe/handle/sunedu/210679

The present study was carried out at the "Carlos Miguel Castañeda Ruiz" Research Center of the IIAP - San Martín Headquarters, located in the Bello Horizonte hamlet of Banda de Shilcayo district, during the months of May 2014-January 2015; aiming to establish a captive reproduction mechanism of the "Brown Carachama"

Hypostomus hemicochliodon

by proposing three treatments: T1 (PVC nests), T2 (Bamboo stem nests) and a control treatment (natural nests), each treatment with 3 replicas, randomly distributed, each replicate in an area of ​​250 m2, with 180 reproducers of Hypostomus hemicochliodon, randomly distributed 20 individuals per experimental unit. After an adaptation period of 60 days, the experimental phase began. The reproductive samplings and physical-chemical parameters of the water in the ponds were carried out every two weeks. 32 reproductive events were obtained, with T0 (59%) being the most responsive, followed by T2 (25%) and T1 (16%). It was concluded statistically (p> 0.05) that there is a significant difference (value p = 0.0191), indicating in the number of individuals obtained, T1 was better (T1> T2> T0). There is also a significant difference in the weight (g) of eggs obtained, indicating that T1 and T2 are equal, and both are greater than those obtained from T0. The results of the physico-chemical parameters of the water indicate that the Hypostomus hemicochliodon reproducers have a wide range of tolerance compared to their natural environment, achieving their reproduction in captivity.

El presente estudio se realizó en el Centro de Investigaciones “Carlos Miguel Castañeda Ruiz” del IIAP – Sede San Martín, ubicado en el caserío Bello Horizonte del distrito Banda de Shilcayo, durante los meses de Mayo del 2014-Enero del 2015; teniendo como objetivo establecer un mecanismo de reproducción en cautiverio de la “Carachama parda” Hypostomus hemicochliodon mediante el planteamiento de tres tratamientos: T1 (Nidos de PVC), T2 (Nidos de tallo de Bambú) y un tratamiento testigo (Nidos naturales), cada tratamiento con 3 réplicas, distribuidas al azar, cada replica en un área de 250 m2, con 180 reproductores de Hypostomus hemicochliodon, repartidos al azar 20 individuos por unidad experimental. Luego de un periodo de adaptación de 60 días, se inició la fase experimental. Se realizó quincenalmente los muestreos de reproducción y de parámetros físico-químicos del agua de los estanques. Se obtuvieron 32 eventos reproductivos, siendo el de mayor respuesta el T0 (59%), seguida del T2 (25%) y el T1 (16%). Se concluyó estadísticamente (p > 0.05) que existe diferencia significativa (valor p = 0,0191), indicando en el número de individuos obtenidos, el T1 fue mejor (T1>T2>T0). Además existe diferencia significativa en el peso (g) de ovas obtenidas, señalando que el T1 y T2 son iguales, y ambos mayores a los obtenidos del T0. Los resultados de los valores de parámetros físico-químicos del agua nos indican que los reproductores de Hypostomus hemicochliodon tienen un amplio rango de tolerancia en comparación a su medio natural, logrando su reproducción en cautiverio.

[bekateen]

MAGALHÃES, Maithê Gaspar Pontes. 2018. Description of Molecular Biodiversity of Hypancistrus zebra (Loricariidae: Siluriformes), a Species of Ornamental Fish Threatened with Extinction. Dissertation (Master's Degree in Computational Biology and Systems) - Instituto Oswaldo Cruz, Oswaldo Cruz Foundation, Rio de Janeiro, 2018.

MAGALHÃES, Maithê Gaspar Pontes. 2018. Descrição da Biodiversidade Molecular de Hypancistrus zebra (Loricariidae: Siluriformes), uma Espécie de Peixe Ornamental Ameaçada de Extinção. 2018. 77 f. Dissertação (Mestrado em Biologia Computacional e Sistemas)-Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, 2018.

https://www.arca.fiocruz.br/handle/icict/28446

ABSTRACT
The impact of human activities on Earth is so deep that a new geological epoch, the Anthropocene, has been widely debated. In this new epoch, biodiversity loss stands out among the key features affecting global health. The construction of dams for hydroelectric power generation has the potential to have a major impact on local fauna, especially in regions with high biodiversity and endemism, such as the Brazilian Amazon.

Hypancistrus zebra

is a species of fish endemic to the Big Bend of the Xingu River, in the Amazon basin, threatened with extinction due to the impact of the Belo Monte Power Plant dam and illegal capture for international fish aquarium. However, until the beginning of this work, only two nucleotide sequences were available from Genbank and the BOLD System, the main public databases of this type of information In this work, seven transcripts of different organs of Hypancistrus zebra were sequenced. We produced more than 200 million readings used to assemble over half a million transcripts. In the generated database, we identified more than 35,000 single nucleotide variants (SNVs) and almost four thousand insertions and deletions (indels) distributed among the seven organs of H. zebra. From the analysis of these data, we developed pairs of primers for amplification of indels identified in six transcripts and of frames with at least three SNVs identified in seven other transcripts. We suggest this set of transcripts as the most suitable for application in works aiming the conservation of this species. Mobile genetic elements of several families were found and expressed in the seven organs. The frequency of transcripts with mobile genetic elements varied from 12% in the transcriptome of the heart to 33% in the gill. In addition, we assembled the mitochondrial genome, with 16,330 bp, of this species. The information and the database produced in this work reduces the knowledge gap on the genetic diversity of Hypancistrus zebra and can be used for population genetics studies and the conservation of this and other phylogenetically close species. This information, especially those related to genetic genetic elements, can also support research on the karyotype variation found in the Loricariidae family, of which H. zebra is a part.

• KEYWORDS: Transcriptome, Mitochondrial Genome, Catfish, Biodiversity

RESUMO
Os impactos das atividades humanas na Terra são tão profundos que a proposta de definição de uma nova época geológica, o Antropoceno, tem sido amplamente debatida. Nesta nova época, a perda da biodiversidade destaca-se entre as principais características que afetam a saúde global. A construção de barragens para geração de energia hidrelétrica tem potencial de causar grande impacto na fauna local, especialmente em regiões com elevada biodiversidade e endemismo, como a Amazônia brasileira. O

Hypancistrus zebra

é uma espécie de peixe endêmico da Volta Grande do rio Xingu, na bacia amazônica, ameaçada de extinção devido ao impacto da construção da barragem da Usina de Belo Monte e à captura ilegal para aquariofilia internacional. Apesar disso, até o início desse trabalho, apenas duas sequências de nucleotídeos eram disponíveis no Genbank e no BOLD System, principais bancos de dados públicos desse tipo de informação. Neste trabalho, foram sequenciados sete transcriptomas de diferentes órgãos de Hypancistrus zebra Produzimos mais de 200 milhões de leituras utilizadas para montar mais de meio milhão de transcritos. Neste banco de dados produzido, identificamos mais de 35 mil variantes de nucleotídeo único (SNVs) e quase quatro mil inserções e deleções (indels) distribuídos entre os transcriptomas dos sete órgãos de H. zebra. A partir da análise desses dados, desenvolvemos pares de iniciadores para amplificação de indels identificados em seis transcritos e de janelas contendo pelo menos três SNVs identificadas em sete outros transcritos. Sugerimos esse conjunto de transcritos como os mais adequados para aplicação em trabalhos visando a conservação dessa espécie. Foram encontrados elementos genéticos móveis de diversas famílias e expressos nos sete órgãos. A frequência de trancritos com elementos genéticos móveis variou de 12% no transcriptoma do coração a 33% na brânquia. Além disso, montamos o genoma mitocondrial, com 16.330 pb, dessa espécie. As informações e o banco de dados produzidos neste trabalho reduzem a lacuna de conhecimento sobre a diversidade genética do Hypancistrus zebra e podem ser usados para estudos de genética de população e da conservação dessa e de outras espécies filogenéticamente próximas. Essas informações, em especial às relacionadas a elementos genéticos móveis, também podem dar apoio à investigação sobre a variação cariotípica encontrada na família Loricariidae, da qual o H. zebra faz parte.

• PALAVRAS-CHAVE: Transcriptoma, Genoma Mitocondrial, Peixes-Gato, Biodiversidade

[bekateen]

EDIT: 20/11/22 - This is now published here.

Ten new species proposed:

• Trichomycterus astromycterus
  sp. nov.
• T. barrocus sp. nov.
• T. brucutu sp. nov.
• T. illuvies sp. nov.
• T. melanopygius sp. nov.
• T. ipatinguensis sp. nov.
• T. pussilipygius sp. nov.
• T. sordislutum sp. nov.
• T. vinnulus sp. nov.
• T. tantalus sp. nov.

Reis, V. J. C. (2018). Diversity of the genus Trichomycterus Valenciennes, 1832 (Siluriformes, Trichomycteridae) in the Rio Doce basin: a systematic study integrating phenotypes, DNA and classical taxonomy. Master's Dissertation, Museu de Zoologia, University of São Paulo, São Paulo. doi:10.11606/D.38.2018.tde-08102018-132640. Retrieved 2019-07-08, from www.teses.usp.br

http://www.teses.usp.br/teses/disponive ... 640/en.php

Reis, V. J. C. (2018). Diversidade do gênero Trichomycterus Valenciennes, 1832 (Siluriformes, Trichomycteridae) na bacia do Rio Doce: um estudo sistemático integrando fenótipos, DNA e taxonomia clássica. (Dissertação, Museu de Zoologia, Universidade de São Paulo).

ABSTRACT
The diversity of the genus

Trichomycterus

Valenciennes 1832 in the Rio Doce basin is investigated using conventional and modern morphology and DNA analyses. The work is presented in two Chapters. Chapter One, entitled Diversity of the genus Trichomycterus Valenciennes, 1832 (Siluriforms, Trichomycteridae) in the Rio Doce basin: a systematic study integrating phenotypes, DNA and classical taxonomy integratively analyzes specimens of the genus from the entire Rio Doce drainage and adjacent basins, both from available world-wide collections and from active sampling efforts. A combination of phenotypic and DNA (COI barcoding analysis) provides evidence for the existence of 14 species in the basin, 10 of which are new: T. alternatus Eigenmann, 1917; T. argos Lezama et al., 2012; T. astromycterus sp. nov.; T. barrocus sp. nov.; T. brucutu sp. nov.; T. brunoi Barbosa & Costa, 2010; T. immaculatus (Eigenmann & Eigenmann, 1889)] T. illuvies sp. nov.; T. melanopygius sp. nov.; T. ipatinguensis sp. nov.; T. pussilipygius sp. nov.; T. sordislutum sp. nov.; T. vinnulus sp. nov; and T. tantalus sp. nov. . In addition, a lectotype is designated for T. immaculatus and the species is considered as a senior synonym of

Trichomycterus pradensis

Sarmento-Soares et al., 2005. Although remarkable, such increase in species number of Trichomycterus in a single drainage matches similar recent increments in some other Southeastern Brazilian basins, such as the Paraíba do Sul and Iguaçu. The kind of differentiation among species herein recognized varies, with some of them being well-differentiated in morphology but not in barcoding data, and others showing the opposite phenomenon. The geographical distribution of each of the 14 species is plotted in the Rio Doce basin. The wide geographical distribution of some species (T. alternatus and T. immaculatus) is explained against data from geomorphological processes and comparative information on their biology. Chapter two, The type specimens of

Trichomycterus alternatus

(Eigenmann, 1917) and T. zonatus (Eigenmann, 1918), with elements for future revisionary work (Teleostei, Siluriformes, Trichomycteridae) focuses on the complex taxonomy, nomenclature and type material status of T. alternatus and T. zonatus. The type series of the two species are analyzed in detail, both in morphology and locality data. Osteological information was obtained with conventional and a new technique of radiographic stereo-triplets. Our new data elucidates their species distinctiveness, diagnostic characteristics, type localities and show that T. zonatus does not occur in the Rio Doce basin.

• Keywords: barcoding, biogeographical dispertion, Integrative taxonomy, Neotropical catfish, species delimitation

RESUMO
A diversidade do gênero

Trichomycterus

Valenciennes 1832 na bacia do Rio Doce é investigada utilizando métodos convencionais e modernos em análises morfológicas e moleculares. Os resultados desta dissertação são apresentados em dois capítulos. Capítulo um, intitulado Diversity of the genus Trichomycterus Valenciennes, 1832 (Siluriforms, Trichomycteridae) in the Rio Doce basin: a systematic study integrating phenotypes, DNA and classical taxonomy examinou espécimes pertencentes a este gênero encontrados no Rio Doce e em bacias adjacentes disponíveis em coleções nacionais e internacionais e coletados durante esta dissertação. O conjunto de dados obtidos através de análises morfológicas e moleculares (COI, DNA barcoding) revelou a existência de 14 espécies na bacia do Rio Doce, das quais 10 novas: T. alternatus Eigenmann, 1917; T. argos Lezama et al., 2012; T. astromycterus sp. nov.; T. barrocus sp. nov.; T. brucutu sp. nov.; T. brunoi Barbosa & Costa, 2010; T. immaculatus (Eigenmann & Eigenmann, 1889)] T. illuvies sp. nov.; T. melanopygius sp. nov.; T. ipatinguensis sp. nov.; T. pussilipygius sp. nov.; T. sordislutum sp. nov.; T. vinnulus sp. nov; and T. tantalus sp. nov. Além disso, é designado um lectótipo para T. immaculatus, espécie aqui proposta como sinônimo sênior de

Trichomycterus pradensis

Sarmento-Soares et al., 2005. O acentuado incremento em número de espécies de Trichomycterus para uma única bacia segue um padrão de crescimento em biodiversidade conhecida do gênero para outras drenagens do sudeste brasileiro a exemplo do rio Paraíba do Sul e Iguaçu. Os tipos de diferenciação detectada entre as espécies aqui tratadas variam, com algumas bem corroboradas morfologicamente, porém muito similares ou indiferenciáveis em análise de DNA barcoding, e outras apresentando o fenômeno oposto. As distribuições geográficas de cada uma das 14 espécies são mapeadas com base em todo o material examinado. A ampla distribuição geográfica de algumas espécies (T. alternatus and T. immaculatus) é explicada através de processos geomorfológicos e informações comparativas sobre suas biologias. O capítulo dois, The type specimens of

Trichomycterus alternatus

(Eigenmann, 1917) and T. zonatus (Eigenmann, 1918), with elements for future revisionary work (Teleostei, Siluriformes, Trichomycteridae) se concentra em esclarecer a complexa taxonomia, nomenclatura e o status do material tipo de T. alternatus e T. zonatus. As séries tipos das duas espécies foram minuciosamente analisadas tanto para morfologia como para suas respectivas localidades de proveniência. Informações osteológicas foram obtidas através de técnicas de radiografia convencionais e uma nova metodologia chamada stereo triplets. Os dados obtidos corroboram as respectivas espécies como distintas, e permitem uma avaliação precisa de seus respectivos caracteres diagnósticos e localidades tipo. Também se chegou à conclusão que T. zonatus não ocorre na bacia do Rio Doce.

• Keywords: bagres neotropicais, barcoding, delimitação de espécies, dispersão biogeográfica, Taxonomia integrativa

[bekateen]

Diaz, Ana Milena. (2018). Evaluation of the physicochemical parameters of the water and the condition of the fins in the real fish (

Panaque nigrolineatus

), during the storage in the export warehouse of Bogotá. De La Salle University, Animal Husbandry Program. Bogotá D.C., June 2018.

http://repository.lasalle.edu.co/handle/10185/28740
Full PDF: http://repository.lasalle.edu.co/bitstr ... sAllowed=y

Diaz, Ana Milena. (2018). Evaluación de parámetros fisicoquímic0s del agua y del estado de las aletas en el pez cucha real (

Panaque nigrolineatus

), durante el acopio en bodega de exportación de Bogotá. Universidad De la Salle, Programa De Zootecnia. Bogotá D.C., Junio De 2018.

ABSTRACT
The family of loricariid fish is typically South American, very diverse in forms, sizes and even in eating habits, there are about 500 species, most are for ornamental use. They are very popular fish in aquariums around the world, as they act as cleaners of the glasses of aquariums, by consuming the algae that adhere to them. The genus

Panaque

or cucha real is a species of singular beauty, desired by aquarists from all over the world. In Colombia they are called buckets and in the world they are called plecos or sucker mouth catfish.

The export of fish is based on the capture, stockpiling, handling in the winery and export, which leads to failures on the part of the fishermen in the way they are caught and the bad handling that is given to the fish, which leads to losses of animals or mistreatment of them at the fins level. The present work seeks to analyze whether water quality and post-capture management affects the survival and quality of the fins in individuals stocked in warehouses, prior to being sent abroad.

Resumen
La familia de los peces loricáridos es típicamente suramericana, muy diversa en formas, tallas
e incluso en hábitos alimentarios, existiendo cerca de 500 especies, la mayoría son de uso
ornamental. Son peces muy populares en los acuarios de todo el mundo, pues actúan como
limpiadores de los vidrios de los acuarios, al consumir las algas que se adhieren a estos. El
género

Panaque

o cucha real es una especie de singular belleza, apetecida por acuarófilos de
todo el mundo. En Colombia se les llama cuchas y en el mundo se les denomina plecos o sucker
mouth catfish.

La exportación de peces se basa en la captura, acopio, manejo en bodega y exportación, lo cual
conlleva fallas por parte de los pescadores en la forma como los capturan y el mal manejo que
se les da a los peces, lo que acarrea pérdidas de animales o maltrato de los mismos a nivel de
aletas. El presente trabajo busca analizar si la calidad del agua y el manejo postcaptura, afecta
la supervivencia y la calidad de las aletas en individuos acopiados en bodegas, previos a ser
enviados al exterior.

[bekateen]

Riley, R. J. (2019). Keeping it together: the effect of familiarity, personality, and active interactions on group coordination. Doctoral thesis, Department of Zoology, University of Cambridge. Doi: 10.17863/CAM.35774

https://www.repository.cam.ac.uk/handle/1810/288486
https://doi.org/10.17863/CAM.35774

ABSTRACT
Group coordination is a universal feature of social life. Animals form social groups for a variety of reasons, including predator evasion and more efficient foraging, and individuals living in social groups must coordinate their activities in order for groups to function. Consequently, the factors that facilitate or impede group coordination are of great interest in understanding the lives of social animals. Familiarity between individuals has well-documented effects on group coordination, with familiar groups outperforming unfamiliar ones in predator evasion, foraging, and cohesion. Individuals also generally prefer to coordinate with familiar conspecifics over unfamiliar ones. Despite these advantages, the mechanisms through which familiarity might aid group coordination are poorly understood. Similarly, the individual personalities of group members have well-documented effects on group performance: bold individuals are more likely to be ‘leaders’ and determine the direction of group movements, and groups comprised of individuals of differing personalities outperform groups of all bold or all shy individuals. While the effect of individual personalities on group behaviour has been recorded extensively, the ways in which individuals affect each other’s behaviour are still poorly documented. In particular, active interactions where one individual can directly affect the behaviour of others have received limited attention, as it is difficult to distinguish such actions from passive effects. I used two systems to investigate how individual behaviours can lead to group coordination. In three-spined sticklebacks (

Gasterosteus aculeatus

), well-established boldness assays allowed me to assess the effects of personality and familiarity on 1) coordination between pairs of fish; I found that individuals in unfamiliar pairs exhibited coordination patterns consistent with their individual personalities, with bold individuals more likely to leave cover independently, while in familiar pairs, individuals behaved in ways seemingly unrelated to their boldness scores. I also investigated how personality and familiarity affect 2) group coordination and individual performance in a problem-solving paradigm. I found that familiarity, relative individual personality, and group mean personality interact to affect individual foraging success, and that group cohesion was affected by the interaction of group familiarity and group mean personality. These results suggest that individual characteristics can impact the behaviour of groups, and that the characteristics of an individual’s group can in turn affect an individual’s behaviour and success. In the Bronze Cory catfish (

Corydoras aeneus

), I described a novel tactile interaction style termed ‘nudging’ that individuals use during group coordination. I investigated 3) the effect of familiarity on nudging and coordination in pairs and triplets. These results show that nudging can be used to overcome the disadvantages of familiarity, which has important implications for how communication can underlie group coordination in the absence of familiarity. I then investigated how 4) nudging affects group coordination following a flight response to a potential threat. I demonstrated that nudging leads to a higher likelihood of group cohesion and longer group flight times. This shows how active interactions can mediate group responses and affect the ecologically relevant scenario of predator evasion. Finally, I investigated 5) the development of this nudging behaviour. My results show that Bronze Cory catfish larvae develop toleration for tactile stimulation with age alongside their propensity to nudge conspecifics. This suggests that Bronze Cory catfish larvae require social feedback to develop appropriate responses to nudges from conspecifics and supports the important role of nudging in Bronze Cory catfish sociality. The presence of active interactions in the Bronze Cory catfish` modifies the way that social behaviour manifests in this species and has great potential for further questions about social behaviour and group functioning.

• Keywords: Social behaviour, familiarity, group coordination

[Horlack]

Developmental and functional analysis of scutes in the armored catfish Corydoras aeneus

Be careful : Not a science news, but a Thesis !

Author : Emily Volk
Source : Undergraduate Honors These , University of Colorado, Boulder, April 4 2019
HTML : https://scholar.colorado.edu/honr_theses/1832/
PDF : https://scholar.colorado.edu/cgi/viewco ... onr_theses

Fish scales are specialized biological structures of current interest in innovative materials design because of the combination of protective function, flexibility, and light weight they offer. This study presents a developmental and functional investigation of a particular fish scale structure, the scutes (bony external plates) of the armored Bronze Corydoras Catfish (Corydoras aeneus). Scutes in this model fish species were analyzed via three complementary approaches. First, scutes were documented throughout fish development via high-quality microscope images. These images were subsequently used to inform fabrication of synthetic models to characterize the relationship between scute overlap and overall bending stiffness of scute assemblies. These models indicated that scute overlap resulted in a 318% increase in bending stiffness. My study also presents insight into how increased bending stiffness could influence the swimming strategy of live larval C. aeneus. By synthesizing the insight from these developmental and functional investigations of the scutes of C. aeneus, my study aims to contribute to a better functional understanding of the evolutionary pathway of C. aeneus as well as inform fabrication of future innovative designs utilizing the unique structure and dynamics of scute assemblies.

[bekateen]

Modertor's note, Mastiglanis sp(1) was described in July 2020 and is now

Mastiglanis yaguas

. (link here: viewtopic.php?f=14&t=49301)

Fuster, D. R. F. (2019). Revisión taxonómica del género Mastiglanis (Bockmann, 1994)(Siluriformes: Heptapteridae) en Perú. Thesis for a Professional Degree in Biology, Universidad Nacional Mayor de San Marcos, Universidad del Perú, Decana de América. Escuela Profesional de Ciencias Biológicas.

http://cybertesis.unmsm.edu.pe/handle/cybertesis/10514
PDF: http://cybertesis.unmsm.edu.pe/bitstrea ... sAllowed=y

NOTE: I've added the two undescribed fish to the CLOG as

Mastiglanis sp(1)

and

Mastiglanis sp(2)

.

ABSTRACT

Mastiglanis

is a monotypic genus, with the type species M. asopos, belonging to Heptapteridae. This freshwater species is widely distributed along the Amazon and Orinoco River basins. In this research, a taxonomic review of specimens collected from the Putumayo and Nanay River, Amazon rivers basin in Peru. The morphological analysis was carried out taking morphometric (36 measurements) and meristic (20 counts) data, with the help of a digital caliper and stereo microscope; some osteological counts and descriptions were made of clear and stained material. This study revealed two new species of Mastiglanis. The two new species of Mastiglanis differ from M. asopos by having short snout. Mastiglanis sp1 is differentiated from its congeners by having eight branched anal fin rays and a large pelvic fin large; additionally, Mastiglanis sp1 is differentiated from M. asopos by having more number of vertebrae, epibranchial spines, ceratobranchial spines, by having a short process in the sinfisial region of the premaxila, thin body, broad interorbital space, big eyes, head tall, and thin. Mastiglanis sp2 differs from all its congeners by having a lower caudal peduncle; additionally, it differs from M. asopos by having a larger eye diameter; and from Mastiglanis sp1 by having more branched anal fin rays, short pelvic-fin, broader head, smaller interorbital space and smaller posterior nostrils space. The two new species are distributed in the Yaguas River, tributary of the Putumayo River; and in the Nanay River tributaries from the Amazon basin, from the Loreto Department, Peru.

• Keywords: small catfish, morphology, freshwater, Peruvian Amazon.

RESUMEN

Mastiglanis

es un género monotípico, con la especie tipo M. asopos, que pertenece a Heptapteridae, esta especie de agua dulce se encuentra ampliamente distribuida a lo largo de los ríos Amazonas y Orinoco. En la investigación se realizó una revisión taxonómica de ejemplares colectados en las cuencas del Putumayo y Amazonas en Perú. El análisis morfológico fue realizado considerando datos morfométricos (36 medidas) y merísticos (20 conteos), con ayuda de un calibrador digital y estéreo microscopio; algunos conteos y descripciones osteológicas fueron realizados de material diafanizado. En este estudio se revelan dos nuevas especies de Mastiglanis. Las dos especies nuevas de Mastiglanis se diferencian de M. asopos por tener el hocico corto. Mastiglanis sp1 se diferencia de sus congéneres por presentar 8 radios ramificados en la aleta anal, aleta pélvica grande, adicionalmente Mastiglanis sp1 es diferenciado de M. asopos por presentar mayor número de vertebras, espinas epibranquiales, espinas ceratobranquiales, por tener el proceso en la región sinfisial de la premaxila corto, cuerpo delgado, espacio interorbital amplio, ojo grande, cabeza alta y delgada. Mastiglanis sp2, se diferencia de todos sus congéneres por presentar el pedúnculo caudal bajo; adicionalmente se diferencia de M. asopos por tener un mayor diámetro del ojo; y de Mastiglanis sp1 por tener más radios anales ramificados, aleta pélvica corta, cabeza ancha, espacio interorbital menor y el espacio entre las narinas posteriores menores. Las dos nuevas especies se encuentran distribuidas en los ríos Yaguas, tributario del rio Putumayo; y en el río Nanay tributario de la cuenca del Amazonas, en el departamento de Loreto, Perú.

• Palabras claves: bagres menudos, morfología, agua dulce, Amazonia Peruana

[bekateen]

Moderator's note: these two species are described now: viewtopic.php?t=50042
Hypostomus sp. nov. A =

Hypostomus cafuringa

Hypostomus sp. nov. B =

Hypostomus crulsi

SOARES, Yan Felipe Figueira. (2019). Description of new species of Hypostomus (Siluriformes: Loricariidae) for Central Brazil. Dissertation (Master in Zoology). University of Brasilia, Brasilia.

https://repositorio.unb.br/handle/10482/35787
PDF: https://repositorio.unb.br/bitstream/10 ... Soares.pdf

ABSTRACT:
We described two new species of

Hypostomus

from central Brazil based on morphological data sets, with lineages previously identified in genomic studies. A machine learning classification procedure (random forest) was used to investigate the morphological variation and to identify species diagnostic characters. The new species Hypostomus sp. nov. A is characterized by the reduced size, dark spots under a light background, deeper caudal peduncle, smaller first ray of the pectoral fin and smaller base of the dorsal fin when compared to its congeners. Hypostomus sp. nov. A is known for the headwaters of the river Maranhão, upper Tocantins river basin, Federal District, Brazil. The second new species Hypostomus sp. nov. B is characterized by dark spots under a light background, absence of plaques in the abdomen, smaller first ray of the pelvic fin, smaller first ray of the pectoral fin and smaller body size. Hypostomus sp. nov. B is known for the headwaters of the São Bartolomeu river, upper Paraná river basin, Federal District Brazil.

RESUMO:
Descrevemos duas novas espécies de

Hypostomus

do Brasil central que foram identificadas previamente em estudos genômicos, promovendo uma descrição com a diagnose baseada em conjuntos de dados morfológicos. Foi utilizado um procedimento de classificação de aprendizado de máquina (random forest) para investigar a variação morfológica e identificar caracteres diagnósticos para as espécies. A nova espécie Hypostomus sp. nov. A é caracterizada pelo tamanho reduzido, pontos escuros sob um fundo claro, altura do pedúnculo caudal maior, primeiro raio da nadadeira peitoral menor e base da nadadeira dorsal menor, quando comparada aos seus congêneres. Hypostomus sp. nov. A é conhecida das cabeceiras do rio Maranhão, bacia do alto rio Tocantins, Distrito Federal, Brasil. A segunda nova espécie Hypostomus sp. nov. B é caracterizada por possuir pontos escuros sob um fundo claro, ausência de placas na região do abdômen, primeiro raio da nadadeira pélvica menor, primeiro raio da nadadeira peitoral menor, tamanho corporal menor. Hypostomus sp. nov. B é conhecida das cabeceiras do rio São Bartolomeu, bacia do alto rio Paraná, Distrito Federal Brasil.

[bekateen]

Martine, G. (2019). Distribuição do ictioplâncton em diferentes micro-habitats do médio Rio Uruguai, Brasil. Dissertação de Mestrado, Programa de Pós Graduação em Ambiente e Tecnologias Sustentáveis da Universidade Federal da Fronteira Sul.

https://rd.uffs.edu.br/handle/prefix/3098
PDF: https://rd.uffs.edu.br/bitstream/prefix ... ARTINE.pdf

ABSTRACT
Research related to ichthyoplankton provides relevant information about its initial development, but for the Uruguay River basin, little is known about which environments are preferred by fish larvae during the early stages of their life cycle. From this, the objective of this work was to evaluate five microhabitats in three sample stations in the middle Uruguay River, located in the municipalities of Porto Mauá, Porto Vera Cruz and São Nicolau, RS, respectively. Monthly collections were carried out at night, from November 2017 to January 2018, totaling 180 samplings. The spatial distribution of the sampling stations lies in a stretch of approximately 150 km. Each sampling station presents four microhabitats in the Uruguay River: rapids, island, margin and well; and one near the mouth of a tributary river: Santa Rosa River (PM), Amandaú River (PVC) and Rio Piratinim (SN). At all points, active collections were carried out from trawls with a mesh of 500 μm conical-cylindrical plankton. The variables: transparency, velocity, temperature, dissolved oxygen, electrical conductivity, pH, depth and river level were measured monthly. The samples collected were fixed in 4% formaldehyde, sorted and identified at the species level. The larval stages considered were: vitelline larval (LV), pre-flexion larval (LP), larval flexion (LF) and post-flexion larval (OLP). 1,523 larvae were captured, four orders, 14 families, 27 genera and 19 species. Of these, 92.12% belong to the Siluriform order, with the Pimelodidae family (89.43%) being the most abundant, being

Parapimelodus valenciennis

(50.10%),

Pimelodus maculatus

(15.30%) and

Iheringichthys labrosus

(8.14%). Migratory fish species were also captured: the Characiformes

Megaleporinus obtusidens

and

Salminus brasiliensis

and the Siluriformes

Luciopimelodus pati

,

Pimelodus maculatus

,

Pseudoplatystoma corruscans

and

Sorubim lima

. There was no statistically significant difference in larval distribution in the collection months (p> 0.05). Regarding the total larvae / 10m3 and the sampling stations, PVC had the highest densities (p <0.05). As for the larval stages and the sampling stations, LV presented the highest density in the PM station (p <0.05). For the larval stages of pre-flexion, flexion and post-flexion, there was a significant statistical difference (p <0.05), in which PVC presented the highest densities. The CCA revealed the most grouped and segregated wells and rapids of the island, margin and tributary (P <0.05) microhabitats. The CCA1 showed that water velocity (p <0.05), depth (p <0.05) and water transparency (p <0.05) were the most important factors for the distribution of larval stages. The LV stage (p <0.05) was positively correlated with water velocity and the greatest depth of the environment. Post-flexion larvae (p <0.05) were mainly related to greater transparency and inversely related to water depth and velocity. The NMDS revealed clear spatial segregation between the channel and island microhabitats of the margin and the tributary. According to the results, it is concluded that the PVC sampling station had the highest densities of fish larvae, and the micro-habitat Ilha represents the site of higher incidence of total larvae, which characterizes it as a nursery of fish larvae in initial stages, mainly Siluriformes.

Keywords: Reproduction of fish. Eggs and larvae. Spatial distribution. Nursery areas. Medium river Uruguay.

[bekateen]

Marden, Caroline Louise. (2019). Characterisation of the microbial communities in the gastrointestinal tract of wood-eating organisms. Doctoral dissertation, University of Portsmouth.

https://ethos.bl.uk/OrderDetails.do?uin ... hos.800220
https://researchportal.port.ac.uk/porta ... d395).html
PDF: https://researchportal.port.ac.uk/porta ... r_viva.pdf

ABSTRACT
Wood recycling is key to biogeochemical cycling and largely driven by microorganisms, with bacteria and fungi naturally coexisting together in the environment. Terrestrial isopods Oniscus asellus and Porcellio scaber have adaptations to enable them to colonise diverse terrestrial environments and scavenge on dead and decaying organic matter that is rich in cellulose. The Amazonian catfish,

Panaque nigrolineatus

have physiological adaptions enabling the scraping and consumption of wood, facilitating a detritivorous dietary strategy. Substrates high in lignocellulose are difficult to degrade and as yet, it is unclear whether these organisms obtain any direct nutritional benefits from ingestion and degradation of lignocellulose. However, there are numerous systems that rely on microbial symbioses to provide energy and other nutritional benefits for host organisms via lignocellulose decomposition. Whilst previous studies on the microbial communities of O. asellus, P. scaber and P. nigrolineatus, have focused upon the bacterial populations, the presence and role of fungi in lignocellulose degradation has not yet been examined. These studies describe the bacterial and fungal communities within the gastrointestinal tracts using next generation sequencing. The hepatopancreas of O. asellus and P. scaber was predominantly colonised by one bacterial species and had more fungal diversity. The hindgut was colonised bymore diverse bacterial and fungal communities. Due to the woodlouse inhabiting diverse environments, including those with heavy metal pollution, culture methods were used to detect antimicrobial resistance in the gastrointestinal tract of woodlice. The effects of diet on enteric fungal populations were examined in each gastrointestinal tract region of P. nigrolineatus and fungal species were found to vary in different regions of the gastrointestinal tract as a function of diet. This is the first study to investigate the bacterial and fungal communities within the hepatopancreas and hindgut from two species of woodlice, using the same individual woodlouse, using next generation sequencing. This is the first study to detect fungi in the digestive tract of any woodlice. This study is the first to examine the fungal community in a xylivorous fish and results support the hypothesis that diet influences fungal distribution and diversity within the gastrointestinal tract of P. nigrolineatus. This study provides new insights into the microbial communities that may have a symbiotic role involved in wood degradation in the GI tracts of woodeating organisms. This study also highlights the need for further research into fungi inhabiting many diverse environments to give more complete and balanced information about the absence and presence of microorganisms.

[bekateen]

REIS, Ryuller Gama Abreu Reis. (2020). Larviculture of acari bread Hypancistrus sp. L333 (Siluriformes Locariidae): food management and stocking density. Dissertation (Master in Aquaculture and Tropical Aquatic Resources) - Federal Rural University of the Amazon, Belém, 2020.

http://repositorio.ufra.edu.br/jspui/ha ... 456789/961

Abstract:
Acari Pão

L333

(Hypancistrus sp.) is an Amazonian species, endemic from the Xingu River, with an important potential for ornamental aquaculture, because its colors and the high value in the market of ornamental aquatic organisms. However, there is little scientific information about the ideal breeding conditions for the species, such as reproduction, larviculture, feed management and nutrition. In this context, one of the major gaps to the captive production of ornamental aquatic organisms is the lack of knowledge about the requirements and food management of the species. The present study aimed to evaluate some managements in the intensive larviculture of Acari Pão L333, more specifically to determine the amount of live food (Artemia nauplii), the stocking density and the time for the food transition from live food to the formulated diet (weaning). The first study was divided into two experiments, where the objective were to evaluate four initial prey concentrations (T100 -100, T200 - 200, T300 - 300 and T400 - 400 nauplii / larvae / day), with amount of prey doubling every six days of the experiment. The second experiment was carried out to determine the ideal stocking density (1, 5, 10, 15 larvae / L) for the species. In the second study, the best time for the weaning was evaluated, in which the substitution was tested after 5, 10, 15 and 20 days of live food supplied. In addition, two treatments were added, in which the larvae received the live food and the formulated diet throughout the experimental period. The results showed that for the larviculture of the species the initial prey concentration of 400 artemia nauplii / larvae / day and the stocking density of 5 larvae / L are recommended. The best period for the weaning was after five days of live food supplied; however, the results of survival with the exclusive use of the formulated diet emerges as a great possibility for future studies on the topic.

• Keywords: Acari bread L333 - Larviculture, Ornamental fish
  Acari bread L333 - Food, Siluriformes Lori, Hypancistrus sp., Ornamental fish culture, Ornamental fish species

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COMMENT: This thesis has some great maps of the area, and also many good photographs of the habitats present along the Xingu. Many diverse rocky and sandy surfaces are shown where loricariids were collected, any of which would probably look neat in an aquarium

Gonçalves, A. P. (2020). Structure of the rheophilic ichthyofauna of the Xingu river, Brazilian Amazon: environmental, spatial and temporal effects on the species distribution pattern. Doctoral Thesis, Biologia de Água Doce e Pesca Interior - BADPI.

Gonçalves, A. P. (2020). Estrutura da ictiofauna reofílica do rio Xingu, Amazônia Brasileira: efeitos ambientais, espaciais e temporais no padrão de distribuição das espécies. Tese, Doutora. Biologia de Água Doce e Pesca Interior - BADPI Doutorado - BADPI.

https://repositorio.inpa.gov.br/handle/1/13016
https://repositorio.inpa.gov.br/bitstre ... cavels.pdf

ABSTRACT
Rapids and waterfalls are environments that have extreme and peculiar environmental characteristics when compared to other river stretches. These sites harbor fish species with unique ecological characteristics, with remarkable morphological and behavioral specializations related to the life in structurally complex environments with fast and turbulent waters. In this study we evaluated the structure of the ichthyofauna in the rapids of Xingu River, aiming to a better understanding of the fish assemblage composition and its spatial and temporal variations. We recorded 160 fish species in the rapids, belonging to 97 genera, 25 families and seven orders. Characiformes presented the highest number of families, and Siluriformes the highest number of species. Fifty-two species are endemic to the Xingu River, 11 species are officially considered under some degree of extinction risk, and not all species are protected by the large mosaic of conservation units in the Xingu River basin. The stretch corresponding to the Volta Grande do Xingu harbors the highest diversity of rheophilic fishes along the analyzed stretch of the river, and some species apparently occur only in that stretch. The Volta Grande do Xingu is one of the largest continuous rapids in the world, but the structure of the fish assemblages of this region varies both seasonaly and regarding local habitat characteristics. The largest variations were observed between the main channel rapids of the Xingu and Bacajá rivers, and between the flooding period compared to the receding and dought periods. Although some species occurred in just a few sites or were more abundant in some periods of the hydrologic cycle, several species occurred in all sampling sites and periods, highlighting the possible role of habitat connectivity along the rapids continuum. However, additional analyses of the distribution and abundance of Loricariidae species in Volta Grande evidenced the role of spatial factors acting at different distance scales, which together with the local structure of microhabitats are essential for the maintenance of the loricariid diversity. Food availability did not have a major influence on the structure of Loricariid assemblages, apparently due to the high availability of food items from epilithic and benthic macroinvertebrates. Despite the biological importance of waterfalls and rapids environments, especially those of Volta Grande, a hydroelectric megadam is installed in the region and a huge gold mining project is being licensed, threatening one of the world's most spectacular river rapids.

RESUMO
As corredeiras e cachoeiras são ambientes que apresentam características ambientais extremas e diferentes da maior parte do curso dos rios. Esses locais abrigam espécies de peixes com características ecológicas peculiares, com especializações morfológicas e comportamentais relacionados à vida em ambientes estruturalmente complexos e com águas rápidas e turbulentas. Neste estudo avaliamos a estrutura da ictiofauna associada aos ambientes de corredeiras do rio Xingu, buscando um melhor entendimento da composição das assembleias de peixes e suas variações espaciais e temporais. Foram registradas 160 espécies de peixes abrigando as corredeiras do rio Xingu, pertencentes a 97 gêneros, 25 famílias e sete ordens. Characiformes apresentou o maior número de famílias e Siluriformes o maior número de espécies. Cinquenta e duas espécies são endêmicas do rio Xingu, 11 espécies são oficialmente consideradas sob algum grau de ameaça de extinção, e nem todas as espécies estão protegidas pelo grande mosaico de unidades de conservação presentes na bacia do rio Xingu. O trecho da Volta Grande do rio Xingu apresenta a maior diversidade de espécies de peixes reofílicos, e algumas espécies ocorrem apenas naquele trecho. A Volta Grande é um dos maiores contínuos de corredeiras do mundo, mas a estrutura das assembleias de peixes dessa região apresenta diferenças em relação aos períodos sazonais e em função das características locais dos sítios de amostragem. As maiores variações foram observada entre as corredeiras do canal principal do rio Xingu e as corredeiras do rio Bacajá, e entre os períodos de enchente em relação à vazante e seca. Embora algumas espécies tenham ocorrido em apenas alguns sítios ou tenham sido mais abundantes em alguns períodos, a Volta Grande apresenta um conjunto de espécies que ocorrem em todos os sítios e períodos, evidenciando o possível papel da conectividade de hábitats ao longo do contínuo de corredeiras. Uma análise mais aprofundada da distribuição e abundância de espécies de Loricariidae na Volta Grande demonstrou que fatores espaciais em diferentes escalas de distância, bem como a estrutura local de micro-hábitats são essenciais para a manutenção das espécies dessa família. Disponibilidade de alimento não apresentou grande influência na estruturação das assembleias de Loricariídeos, aparentemente devido à alta disponibilidade de itens alimentares do epilíton e de macroinvertebrados bentônicos. Apesar da importância biológica dos ambientes de cachoeiras e corredeiras, em especial as da Volta Grande, um megaprojeto hidrelétrico está sendo finalizado nessa região e há projetos de mineração de ouro sendo licenciados, colocando em risco uma das áreas de corredeiras mais excepcionais do mundo.

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Valverde Tobar, C. L. (2020). Morphological aspects of Transancistrus santarosensis (Loricariidae) present in the trans-Andean basins of the Andes Mountains of Ecuador. Thesis, University of Guayaquil.

http://repositorio.ug.edu.ec/handle/redug/48681
PDF: http://repositorio.ug.edu.ec/bitstream/ ... 0%20CD.pdf

ABSTRACT
Geometric morphometry is the application of statistical analysis about the variation in the real shape of organisms and can be used to differentiate populations or species. This study focuses on comparing the morphological and bone variations of

Transancistrus santarosensis

in different locations in the western part of the Andes Mountains of Ecuador. The samples of T. santarosensis were obtained in the basins of the Caluma, BuluBulu, Tenguel and Santa Rosa rivers in a range of 100 to 280 masl. A total of 65 specimens of T. santarosensis were analyzed and the size ranges ranged from 5.1 to 12.5 mm in total length. Regarding the consensus form of the specimens from each locality, significant differences p <0.0005 were observed. The northern specimens presented a reduction between the anal fin and the caudal fin, as well as between the dorsal and adipose fins; in addition, a reduction in the abdomen was observed in the southern specimens. The specimens from the four localities showed no differences in the morphology of the cephalic plates. The morphology of the plates is characteristic at the gender level since the same morphological characters are observed in T. aequinoctialis.

• Keywords: Geometric morphometry, Morphological variations, Consensus shape, Cephalic plates, Alizarin red.

Valverde Tobar, C. L. (2020). Aspectos morfológicos de Transancistrus santarosensis (Loricariidae) presentes en las cuencas transandinas de la Cordillera de los Andes de Ecuador. Tesis, Universidad de Guayaquil.

RESUMEN
La morfometría geométrica es la aplicación de análisis estadísticos acerca de la variación de la forma real de los organismos y puede ser utilizada para diferenciar poblaciones o especies. Este estudio se enfoca en comparar las variaciones morfológicas y óseos de

Transancistrus santarosensis

en distintas localidades de la zona occidental de la Cordillera de los Andes de Ecuador. Las muestras de T. santarosensis fueron obtenidos en las cuencas de los Ríos Caluma, BuluBulu, Tenguel y Santa Rosa en un rango de 100 a 280 msnm. Se analizaron en total 65 especímenes de T. santarosensis y los rangos de tallas oscilaron entre 5.1 a 12,5 mm de longitud total. En cuanto a la forma consenso de los especímenes de cada localidad, se observó diferencias significativas p < 0.0005. Los especímenes del norte presentaron una reducción entre la aleta anal y la aleta caudal, así mismo entre la aleta dorsal y la adiposa; además se observó una reducción en el abdomen en los especímenes del sur. Los especímenes de las cuatro localidades no mostraron diferencias en la morfología de las placas cefálicas. L a morfología de las placas es característica a nivel de género ya que, en T. aequinoctialis se observan los mismos caracteres morfológicos.

• PALABRAS CLAVES:
  Morfometría geométrica, variaciones morfológicas, forma
  consenso, placas cefálicas, rojo alizarina

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Dwyer, T. W. (2020). Human Mortality Rate of Noodling Catfish in Oklahoma (Doctoral dissertation, University of Central Oklahoma).

https://search.proquest.com/docview/245 ... nview=true

Noodling is a legal method of catching certain species of fish in the state of Oklahoma and in other states in the South and Midwest. Unlike other forms of angling, noodling requires that the angler be in the same physical aquatic environment as the targeted animal without the aid of equipment such as rods, reels, and nets. The peril of this method of fishing is apparent in the numerous injuries reported annually in Oklahoma. In addition, anglers are sometimes killed while noodling. Other forms of fishing, both sport and commercial, are much more common and have better documentation and regulations pertaining to their dangers. For example, commercial fishing in the Pacific Northwest carries great risk associated with the occupation; long hours at sea, hazardous environments, sleep deprivation, and heavy equipment account for the lives of commercial fisherman each season. Prior research has shown that some commercial fishing occupations are, per capita, among the deadliest jobs in the world (Davis, 2012). Through statistical analysis and case studies of noodling deaths, this research sought to determine if, in comparison to the well-documented deadly occupation of commercial fishing, noodling ranks as one of the most hazardous types of fishing on the planet. While far fewer people participate in hand-fishing, the data indicate that, per capita, it is extremely dangerous when compared to other types of fishing. Thus, the regulating authorities should educate participants of the risks, and perhaps formulate additional policies to prevent the further unnecessary loss of life.

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Jesus, T. S. (2020). Feeding habits and morphological relationships of species of Loricariidae (Actinopterygii: Siluriformes) from the Volta Grande region of the Xingu River, Pará, Brazil. Dissertation, Masters of Biological Sciences, National Institute of Amazonian Research.

Jesus, T. S. (2020). Hábitos alimentares e relações morfológicas de espécies de Loricariidae (Actinopterygii: Siluriformes) da região da Volta Grande do rio Xingu, Pará, Brasil. Dissertação, Mestre em Ciências Biológicas, Instituto Nacional de Pesquisas da Amazônia.

https://repositorio.inpa.gov.br/handle/1/36384
PDF: https://repositorio.inpa.gov.br/bitstre ... 0Jesus.pdf

The relationship between morphological attributes and foraging habits was analyzed in 13 species of Loricariidae from Volta Grande do Xingu. We investigated the degree of similarity of morphological characteristics related to obtaining and processing food; and whether the composition of the species' diet is associated with the morphological features. Field collections were carried out between the years 2012 and 2013, including the receding water (July) and low water (September, October, and November) periods in the Volta Grande do Xingu region. The fish capture was carried out throughout direct search, through diving sessions, gillnets, and nets. A total of 185 individuals were used for morphological and diet analysis. 21 morphological attributes associated with food capture and assimilation were selected and analyzed by ordering methods, (Principal coordinate analysis (PCoA) and grouping (Cluster)), which allowed the visualization of morphological patterns between the species of the subfamilies Hypoptopomatinae, Hypostominae and Loricariinae. The analysis of the species diet indicated a broad diet spectrum, with 33 types of alimentary items identified. The Alimentary Importance Index (IAi) was used to identify the main alimentary items for each species, and according to the results, the species were classified into five trophic categories: detritivore, algivore, carnivore, omnivore, and xylophage. The non-metric multidimensional scaling (nMDS) and Cluster identified different trophic patterns and the use of alimentary resources by the species. The correlations between morphology and diet were tested by the Mantel test and a correlation was found between them, indicating that the morphological patterns are related to the feeding habits of the analyzed species, meaning that, the more different the morphologies, the more distinct the diets. Overall, our results show that the diversity of identified alimentary items demonstrated that diet among loricariids can be quite distinct, the importance of rapids environments for the trophic dynamics of these species and that the morphological variety of the digestive tract among species of Loricariidae may have allowed the success in the exploration of different food resources.

As relações entre atributos morfológicos e hábitos alimentares foram analisadas em 13 espécies de Loricariidae da Volta Grande do rio Xingu. Foi investigado o grau de similaridade de características morfológicas relacionadas à obtenção e processamento do alimento, e se a composição da dieta das espécies está associada às características morfológicas mensuradas. As coletas foram realizadas entre os anos de 2012 e 2013 compreendendo os períodos de vazante (julho) e seca (setembro, outubro e novembro) na região da Volta Grande do Xingu. A captura dos peixes foi realizada através da busca direta, por meio de sessões de mergulho, redes de emalhar e tarrafas. Um total de 185 exemplares foram utilizados para análises morfológicas e de dieta. Foram analisados 21 atributos morfológicos associados à captura e assimilação de alimentos e analisados por métodos de ordenação (Análise de coordenadas principais (PCoA) e agrupamento (Cluster)), o que permitiu a comparação de padrões morfológicos entre as espécies das subfamílias Hypoptopomatinae, Hypostominae e Loricariinae. A análise da dieta das espécies indicou um amplo espectro alimentar, tendo sido identificados 33 tipos de itens alimentares. O Índice de Importância Alimentar (IAi) foi utilizado para identificar os principais itens consumidos por cada espécie, e de acordo com os resultados, as espécies foram classificadas em cinco categorias tróficas: detritívora, algívora, carnívora, onívora e xilófaga. As análises de escalonamento multidimensional não-métrico (nMDS) e de agrupamento identificaram diferentes padrões tróficos e de uso dos recursos alimentares pelas espécies. As correlações entre morfologia e dieta foram testadas pelo teste de Mantel e constatada correlação entre elas, indicando que os padrões morfológicos são relacionados aos hábitos alimentares das espécies analisadas, ou seja, quanto mais diferentes as morfologias, mais distintas são as dietas. Finalmente, a diversidade de itens alimentares identificados demonstra a importância dos ambientes de corredeira para a dinâmica trófica dessas espécies e que a variedade morfológica do trato digestório entre as espécies de Loricariidae pode ter permitido o sucesso na exploração de diferentes recursos alimentares.

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Almeida, R. B. D. 2019. Delimitação de espécies e filogeografia molecular comparada para Isbrueckerichthys (Siluriformes: Loricariidae): a influência de captura de rios na história evolutiva.

https://www.acervodigital.ufpr.br/handle/1884/71311

ABSTRACT
The evolution and distribution of Neotropical fish are strictly linked to geologic events of dispersion. An important mechanism that promote the species dispersion and the evolution of fishes is the event known as headwaters capture or river capture. This kind of geological events interconnects adjacent basins and isolate the ones that were previously connected, promoting at same time the isolation (vicariance) and the dispersion (geodispersion) of fish species. In Brazilian south/southeast regions geographical alterations promoted events of river capture and faunal interchange between coastal drainages and higher of the Brazilian crystalline shield. The genus

Isbrueckerichthys

(Loricariidae: Neoplecostominae) is endemic of Brazilian south/southeast, making them a key group to understand the evolutive effects of river capture events in these regions. The aim of this work was to infer patterns of geographic distribution and genetic diversity of Isbrueckerichthys in bordering regions of the Ponta Grossa Arch for the Ribeira de Iguape and Tibagi rivers basins. Also, to prospect the evolutionary history associated with geologic events of river capture in the group diversification. For this purpose, were performed molecular identification and species delimitation analysis of DNA barcoding and GMYC using cytochrome c oxidase subunit I. For the populational investigations were performed Analysis of Molecular Variance and diversity, phylogenetic and phylogeographical inferences, molecular clock, besides the population genetics index, as ΦST, haplotipic diversity, nucleotic diversity, haplotipic diversity, haplotipic network, Mantel Test and bayesian analysis of structuration. I. calvus and I. saxicola behaves as a single taxonomic category both in relation to K2P genetic divergence (1,32% ±0,022%), as in GMYC and phylogenetic inferences. Populational analysis shown a high haplotipic diversity (h) = 0,859 and nucleotic diversity (π) = 0,05026. Mantel Test shown a strong positive correlation among geographic distribution and genetic diversity. Analysis also shown a scenario where the Isbrueckerichthys ancestral reaches the higher lands from the coastal Drainages through a river capture process about 12 million years ago. The results confirm the hypothesis that driver capture events in Ponta Grossa Arch region contributes for the diversity and shape their distribution in Tibagi river basin, and proposes the incipient speciation among I. saxicola e I. calvus in this region.

Key-words: biogeography, headwaters capture, species delimitation, GMYC

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Kubicek, Kole Matthew (2020). Investigation of Ontogeny, Homology and Heterochrony in the Siluriform Skeleton. Doctoral dissertation, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /193002.

https://oaktrust.library.tamu.edu/handle/1969.1/193002

Catfishes (Otophysi: Siluriformes) is a remarkably diverse assemblage (~4000 spp) that is distributed across the globe in fresh and marine waters. Catfishes are united by several modifications of the skeleton, including the extreme modification of certain elements (e.g., the pectoral-fin spine) and the presence of several bones that are currently presumed to be the result of fusion (e.g., the parieto-supraoccipital). In light of this, there have been a vast number of anatomical investigations of the adult skeleton in catfishes; however, comprehensive information on early development of the skeleton remains scarce. This dissertation reports detailed information on the development of the skeleton in catfishes to address issues of homology, provide ontogenetic information on a systematically important character complex, and assess the role that heterochrony may have played in the evolution of the skeleton. I provide a detailed description of skeletal development for two species of North American catfish, Ictalurus punctatus and Noturus gyrinus. Development of the skeleton was complete by 22.4 mm SL in I. punctatus and 14.1 mm SL in N. gyrinus, excluding the dorsal- and anal-fin distal radials in the latter. No major differences were identified between the ossification sequences compiled for each species. No signs of ontogenetic fusion were observed in previously purported compound elements. I also examined the development of the pectoral-fin spine across the order to determine if it develops from a single ontogenetic pathway and standardize terminology of the spine ornamentation for use in systematic studies. The earliest stages of pectoral-fin spine development were highly conserved across the order and most of the morphological diversity of the structure can be attributed to the presence/absence of five traits (distal rami, anterior/posterior serrae, denticuli, and odontodes). Finally, I compare the ossification sequences of four catfishes and 3 non-siluriform otophysans in order to determine what heterochronic shifts (changes in the relative timing of developmental events), if any, are characteristic of catfishes. Eight different bones were found to be shifted in their appearance within the ossification sequence of catfishes, including the morphologically diverse and functionally important pectoral-fin spine.

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Dantas, O. B. (2022). Geographic distribution of Parotocinclus jumbo complex species (Loricariidae, Hypoptopomatinae) in drainages in northeastern Brazil. Bachelor's thesis, Universidade Federal do Rio Grande do Norte, Natal.

Dantas, O.B. (2022). Distribuição geográfica das espécies do complexo de Parotocinclus jumbo (Loricariidae, Hypoptopomatinae) nas drenagens do nordeste do Brasil. Trabalho de conclusão de curso (Graduação em Ciências Biológicas) – Universidade Federal do Rio Grande do Norte, Natal.

https://repositorio.ufrn.br/handle/123456789/46847
PDF: https://repositorio.ufrn.br/bitstream/1 ... s_2022.pdf

Abstract
The genus Parotocinclus has many beetle species described from the watersheds of Northeastern Brazil, mainly in the Caatinga. Most of these fish have a restricted geographic distribution, usually occurring in a single basin, including endangered species. However,

Parotocinclus jumbo

has a wide geographic distribution, known in several basins in the Northeast region. In an integrative taxonomy study of this beetle from six of the eight basins in which it occurs, it was indicated that P. jumbo is a species complex with at least four new species [emphasis added], which are in the description phase. Thus, in this work we address some taxonomic uncertainties involving morphological and molecular data of two P. jumbo lineages, which occur in the Coruripe and Capibaribe river basins. The results here suggest that these two lineages belong to the species already identified and in the description phase, with the lineage that occurs in the Capibaribe River belonging to P. jumbo, which also occurs in the Rio Paraíba do Norte, and the lineage present in the Rio Coruripe belonging to Parotocinclus sp. n. 3, present in the basins of the Paraíba do Meio and Ipojuca rivers. Therefore, we suggest the expansion of the geographic distribution of these species so that P. jumbo registers occurrence in the basins of the rivers Paraíba do Norte and Capibaribe; and Parotocinclus sp. n. 3 records occurrence in the basins of the Ipojuca, Paraíba do Meio and Coruripe rivers, being the only species of the group with presence in basins inserted in the Atlantic Forest and Caatinga biomes, which includes relevant information to assess their conservation status.

Keywords: Integrative taxonomy; Caatinga fishes; Morphology; Genetics; Coastal basins

Resumo
O gênero Parotocinclus possui muitas espécies de cascudinhos descritas das bacias hidrográficas do Nordeste do Brasil, principalmente na Caatinga. A maioria desses peixes apresenta distribuição geográfica restrita, geralmente ocorrendo em uma única bacia, incluindo espécies ameaçadas de extinção. No entanto,

Parotocinclus jumbo

, possui uma ampla distribuição geográfica, conhecida em diversas bacias da região do Nordeste. Em um estudo de taxonomia integrativa desse cascudinho de seis das oito bacias em que ocorre, indicou que P. jumbo se trata de um complexo de espécies com pelo menos quatro espécies novas, que estão em fase de descrição. Com isso, neste trabalho tratamos algumas incertezas taxonômicas envolvendo dados morfológicos e moleculares de duas linhagens de P. jumbo, as quais ocorrem nas bacias dos rios Coruripe e Capibaribe. Os resultados aqui sugerem que essas duas linhagens pertencem às espécies já identificadas e em fase de descrição, sendo a linhagem que ocorre no Rio Capibaribe pertencente a P. jumbo, que também ocorre no Rio Paraíba do Norte, e a linhagem presente no Rio Coruripe pertencente a Parotocinclus sp. n. 3, presente nas bacias dos rios Paraíba do Meio e Ipojuca. Portanto, sugerimos a expansão da distribuição geográfica dessas espécies de modo que P. jumbo registra ocorrência nas bacias dos rios Paraíba do Norte e Capibaribe; e Parotocinclus sp. n. 3 registra ocorrência nas bacias dos rios Ipojuca, Paraíba do Meio e Coruripe, sendo as únicas espécies do grupo com presença em bacias inseridas nos biomas de Mata Atlântica e Caatinga, o que contempla com informações relevantes para avaliar o seu estado de conservação.

Palavras chaves: Taxonomia integrativa; Peixes da Caatinga; Morfologia; Genética; Bacias costeiras

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Akin, D. (2022). Descriptions and Phylogenetic Relationships of the Guiana Shield Pencil Catfishes. Master's Thesis, Auburn University.

https://etd.auburn.edu/handle/10415/8300

The systematics of the catfish genus

Trichomycterus

Valenciennes 1832 are complicated and unresolved. This genus is paraphyletic, containing all members of the Trichomycterinae that cannot be adequately placed into an established genus due to the paucity of clearly defining characters that separated the lineages within this subfamily. The complete revision of

Trichomycterus

is a daunting task, and one that cannot be undertaken until most of the diversity within geographically relevant clades are described. This study describes six new species of

Trichomycterus

of the Pakaraima Mountains and nearby Kusad Mountain of the Guiana Shield region of South America. Additionally, I explore the phylogenetic relationships of these species and construct a time-calibrated phylogeny of the

Eremophilus

lineage within the Trichomycterinae. The results presented here suggest that there are two clades of

Trichomycterus

in the Guiana Shield, one species described in this study may constitute a species complex, that the diversification within the

Eremophilus

lineage occurred concurrently with the rise of the Andes Mountains, and that upper portion of the Ireng River may have flown north into the Grand Pakaraima River before being captured by the modern-day Rio Branco.