Ichthyologists from the USA and Venezuela have described a new species of bristlenose plecs (Ancistrus) from northern Venezuela.
Donald Taphorn, Jonathan Armbruster and Douglas Rodríguez-Olarte name the new catfish Ancistrus falconensis in a recent issue of the journal Zootaxa.
The new species is known from the Hueque and Ricoa Rivers, small, isolated Caribbean drainages of northwest Falcón state (after which the species is named), Venezuela.
According to the authors, “Falcón state is arid in the area of the type locality of A. falconensis, and water resources face increasing demands for urban, agricultural and industrial uses.
“Deforestation, river channelization and water diversion heavily impact most coastal streams, causing accelerating habitat loss and degradation. Thus, this new species must be considered vulnerable to extinction.”
Identification
Ancistrus falconensis is distinguished from A. martini, the species occupying adjacent river drainages to the west of its range in the lake Maracaibo Basin (but separated by an expanse of arid coastal desert where no species of Ancistrus have been found) by color pattern: A. falconensis lacks distinct, light rounded spots on nose, tentacles and sides of the body (vs. present) and lacks dark spots on the spines and rays of all fins (vs. present).
Ancistrus falconensis can be separated from A. gymnorhynchus, the species in adjacent watersheds to the south of its range by almost always having light spots on the abdomen of adults (vs. abdomen almost always uniformly gray in adults) and by the following ratios in specimens greater than 60 mm standard length: mouth width/pectoral spine length (0.66–0.92 vs. 0.48–0.67), dentary tooth cup length/pectoral spine length (0.21–0.26 vs. 0.14–0.22), and premaxillary tooth cup length/pectoral spine length (0.15–0.22 vs. 0.22–0.32).
Ancistrus falconensis can be distinguished from A. triradiatus, which is present in adjacent drainages to the south, but uncommon, by color pattern: A. falconensis lacks rows of dark spots on the dorsal, caudal, pectoral and pelvic fins (vs. present) and A. falconensis has small white spots on the abdomen (vs. absent).
For more information, see the paper: Taphorn, DC, JW Armbruster & D Rodríguez-Olarte (2010) Ancistrus falconensis n. sp. and A. gymnorhynchus Kner (Siluriformes: Loricariidae) from central Venezuelan Caribbean coastal streams. Zootaxa 2345, pp. 19–32.