Rhinotridens chromocaudatus, new genus and species from the Rio Purus drainage
Posted: 21 Oct 2023, 18:01
, new genus and species
Datovo A, Ochoa L, Vita L, Presti P, Ohara WM, de Pinna MCC. A new genus and species of miniature tridentine catfish from the Amazon basin (Siluriformes: Trichomycteridae). Neotrop Ichthyol. 2023; 21(3):e230076. https://doi.org/10.1590/1982-0224-2023-0076
https://www.scielo.br/j/ni/a/zYNSQkgR6t ... k/?lang=en
Datovo A, Ochoa L, Vita L, Presti P, Ohara WM, de Pinna MCC. A new genus and species of miniature tridentine catfish from the Amazon basin (Siluriformes: Trichomycteridae). Neotrop Ichthyol. 2023; 21(3):e230076. https://doi.org/10.1590/1982-0224-2023-0076
https://www.scielo.br/j/ni/a/zYNSQkgR6t ... k/?lang=en
Keywords: Freshwater; Loricarioidei; Ostariophysi; Systematics; TaxonomyAbstract
A new miniature tridentine catfish is described from the rio Purus drainage, Amazon basin, Brazil. It differs from all other tridentines in having several unique autapomorphies: conspicuous anteromedial protuberance in the snout; set of symphyseal premaxillary and dentary teeth inclined posteromedially; distal process of the hyomandibula directed anteriorly; rod-like orbitosphenoid ossified only ventral to the optic nerve; mesethmoid cornua inclined ventrolaterally; opercular and interopercular odontodophores separated by a large interspace; basipterygia fused sagittally; and conspicuous dark brown horizontal stripe in the middle of the caudal fin. The new taxon is hypothesized to be sister to the clade formed by Tridensimilis and Tridens. A detailed osteological description of the new taxon is provided based on X-ray microcomputed tomography (µCT-scans) data and on cleared and stained specimens. Our analysis also reveals that “Tridens” brevis, an enigmatic species that has been indecisively assigned to three different tridentine genera over the past 134 years, belongs to Tridentopsis.Consequently, Tridensimilis is a monotypic genus that currently includes only T. venezuelae.