Tuesday, January 22, 2013

[Ichthyology • 2010] Microlepidogaster longicolla • A new species of Microlepidogaster (Siluriformes: Loricariidae: Hypoptopomatinae) from the upper rio Paraná basin, Brazil



Microlepidogaster longicolla Calegari & R. E. dos Reis 2010

Abstract
Microlepidogaster longicolla, new species, is described from the rio São João of the upper rio Paraná basin near Brasília, in central Brazil. The new species differs from M. perforatus, the only other species in this genus, by having a continuous lateral line, median lateral plate series reaching, rather than falling short of, the end of the caudal peduncle, a shorter pectoral-fin spine (13.4-16.2 vs. 18.2-21.0% standard length), a smaller interorbital distance (38.9-43.1 vs. 47.7-53.3% head length), and more numerous dentary teeth (16-29 vs. 12-15), in addition to several osteological features. Microlepidogaster longicolla shows a remarkable suite of secondary sexually dimorphic characters, involving the presence of a conical urogenital papilla in males, the presence of a fleshy flap along the dorsal margin of first thickened pelvic-fin ray of males, longer pelvic fin in males, and a more strongly arched first pelvic-fin ray in females. 

Key words: Teleostei, Neotropical, Taxonomy, Catfish, Cascudinhos.

Etymology. The species epithet, longicolla, is from the Latin longus, long and collum, neck, meaning long-necked in allusion to the long predorsal region resulting from the posterior shift of the dorsal fin. An adjective.


Calegari, B.B. & Reis, R.E. 2010 A new species of Microlepidogaster (Siluriformes: Loricariidae: Hypoptopomatinae) from the upper rio Paraná basin, Brazil. Neotropical Ichthyology. 8(3), 625–630.