Osteology and myology of Pimelodus blochii

[Shane]

A new article on catfishes has been published:

European Journal of Morphology
Volume 42, Number 3 / July 2005

Osteology and myology of the cephalic region and pectoral girdle of
Pimelodus blochii, comparison with other pimelodines, and comments on the
synapomorphies and phylogenetic relationships of the Pimelodinae
(Ostariophysi: Siluriformes)

R Diogo

Abstract: The cephalic and pectoral girdle structures of the pimelodin
Pimelodus blochii (Pimelodus group) are described and compared to those of
representatives of the two other main pimelodin groups, namely Calophysus
macropterus (Calophysus group) and Pseudoplatystoma fasciatum (Sorubim
group), and of a representative of the peculiar pimelodin genus
Hypophthalmus, H. edentatus, and several other catfishes, as the
foundation for a discussion on the synapomorphies and phylogenetic
relationships of the Pimelodinae. Three new, additional potential
synapomorphies to support the monophyly of the Pimelodinae are pointed
out: (1) presence of a â??muscle 1 of the mandibular barbelsâ?? running from
the antero-ventro-mesial surface of the cartilaginous plates carrying
these barbels to the dentaries; (2) presence of a muscle tensor tripodis
running from the posterior surface of the neurocranium to the dorsal
surface of the swimbladder near the tripus; and (3) presence of a
â??drumming muscle of the swimbladderâ?? running from the parapophyses of the
fourth vertebra and, eventually, the posterior surface of the
neurocranium, to the antero and antero-ventral surface of the swimbladder.
The subfamilies Pimelodinae, Heptapterinae and Pseudopimelodinae seem to
constitute a monophyletic assemblage, thus contradicting the commonly
accepted idea that the family Pimelodidae is a polyphyletic clade.