A new species of cave catfish has been described from Colombia.
The description of the new catfish, named Trichomycterus santanderensis, by Cesar Castellanos-Morales is published in the latest issue of the journal Zootaxa.
The new species is known from the El Puente Cave in the upper Lebrija River drainage in northeast Colombia, and is named after its type locality (the cave lies within the Santander Department).
Trichomycterus santanderensis can be distinguished from other members of the genus in having the eyes variably reduced (from visible to imperceptible due to covering by thick skin), deep head, wide mouth, long barbels, the first pectoral-fin ray extended as a filament that is about 95% of the pectoral-fin length, and light-red pigmentation.
The cave where the catfish were discovered is oriented vertically with narrow, rocky passageways and galleries.
Small, shallow wells in which the catfish reside are found on the cave floor; the bottom of the wells are rocky and sediment-rich and the water was relatively cool (21.5C).
There are three other Trichomycterus species restricted to caves: T. chaberti (Umayalanta Cave in Bolivia), T. itacarambiensis (Olhos d gua Cave in Brazil) and T. spelaeus (Punto Fijo Cave in Venezuela). Trichomycterus santanderensis is distinguished from T. chaberti in having a more anteriorly-oriented dorsal fin with respect to the pelvic fin and longer filament on the first pectoral-fin ray.
It differs from T. itacarambiensis in having a more posteriorly-oriented pelvic and anal fins with respect to the dorsal fin, and from T. spelaeus in having variably reduced eyes, wider mouth and the tip of the pelvic fin reaching the anal-fin base.
For more information, see the paper: Castellanos-Morales, CA (2007) Trichomycterus santanderensis: A new species of troglomorphic catfish (Siluriformes, Trichomycteridae) from Colombia. Zootaxa 1541, 49"55.