The largest catfish family just got larger, with the descriptions of two new species of plecs (Loricariidae) in two new genera by loricariid experts Nathan Lujan and Jonathan Armbruster.
The descriptions of Micracanthicus vandragti and Soromonichthys stearleyi, both from the Orinoco River drainage in Venezuela, were published in the latest issue of the journal Copeia.
Micracanthicus vandragti (pictured above)
This species has been imported into the aquarium trade as L280, and is named after Randy Van Dragt, Professor of Biology at Calvin College since 1981, whose patient introductions to tropical ecology and fish ecomorphology benefited the first author immeasurably.
It is known from the lower Ventuari River and the Orinoco River near its confluence with the Ventuari.
Micracanthicus vandragti is distinguished from other plecs in having the teeth on the lower jaw with longer shafts and larger cusps than those on the upper jaw, enlarged swim bladder and bladder capsules, short tooth cups on the lower jaw bones, four to five predorsal plates of varying sizes and irregular arrangement, an oval oral disc, seven dorsal-fin rays, lacking plates on the abdomen, separate dorsal and adipose fins, and a pointed snout.
This species was collected in shallow, rocky parts of the Ventuari River.
An analysis of gut contents and gut morphology suggests that it is carnivorous and feeds on invertebrates.
Soromonichthys stearleyi
This species has a unique pattern of plate loss on its snout, which distinguishes it from other plecs: plates are absent from the mesethmoid surface and the front margin of the snout.
It is additionally distinguished by its green body with small yellow-gold spots on the head and thin vertical bars on the body, and the presence of seven dorsal-fin rays.
Soromonichthys stearleyi is known only from the Soromoni Creek, a clearwater tributary of the upper Orinoco River, where it was collected from shallow riffles and runs over clean cobble substrate interspersed with sand and patches of a rooted, moss-like aquatic macrophyte.
The species is named after Ralph Stearley, Professor of Geology at Calvin College since 1992, whose patient introductory tutelage in fish osteology set the first author on his career.
For more information, see the paper: Lujan, NK and JW Armbruster (2011) Two new genera and species of Ancistrini (Siluriformes: Loricariidae) from the Western Guiana Shield. Copeia 2011, pp. 216–225.
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