Scientists have described four new species of loricariid catfish from the genus Hypancistrus.
Jonathan Armbruster, Nathan Lujan and Donald Taphorn described the four new species as Hypancistrus contradens, H. debilittera, H. furunculus and H. lunaorum in a paper in the latest issue of the journal Copeia.
All four of the new suckermouth catfishes were discovered in the upper Rio Orinoco in southern Venezuela.
Hypancistrus contradensHypancistrus contradens was caught in the Rio Ventuari and Rio Orinoco in Venezuela and is dark in colour with small white spots.
The species, which has been sold in the aquarium trade as L201, can be confused with H. lunaorum and H. inspector.
The authors said that contradens can be distinguished "from H. lunaorum by having the spots larger than the nasal aperture diameter (vs. spots smaller then the nasal aperture diameter or absent); and from H. inspector (Fig. 3) by having the adpressed dorsal fin reaching the adipose-fin spine (vs. not reaching), the spots on the head the same size as the rest of the body (vs. much smaller on the head), the spots on the caudal fin all free (vs. spots in the upper lobes combining to form bands), and 22-23 (only one of 29 with 24) plates in the mid-ventral series (vs. 24)."
The species is believed to be an omnivorous grazer of aufwuchs. Stomach analyses revealed organic and inorganic matter, including filamentous algae.
Most specimens were collected on bedrock or the cracks between it.
The species is known from the lower reaches of the Rio Ventuari and the main channel of the Orinoco near the mouth of the Ventuari. Juveniles, which may be H. contradens or a related species, have also been recorded from the Rio Casiquiare and the Rio Negro.
Hypancistrus debilitteraHypancistrus debilittera was discovered in the Rio Orinoco at Puerto Ayacucho, just north of San Fernando de Atabapo.
Like contradens, H. debilittera was also found on bedrock in slow or moderate flowing water, and probably fills a similar trophic niche.
The species is grey with a highly variable pattern of spots, bars and vermiculations.
Hypancistrus furunculusHypancistrus furunculus is black to dark grey species with a series of bars on the flanks and dorsal fin.
The species was discovered in the mainstream Rio Orinoco, just west of San Fernando de Atabapo near the mouth of the Rio Ventuari. The type specimens were purchased from aquarium collectors operating in the area.
The species gets its name from the Latin furunculus, which means pilferer, and refers to the bandit-like mask over the eyes of this species.
Hypancistrus lunaorumHypancistrus lunaorum was discovered in the Rio Ventuari, where it lives in flowing water on bedrock outcrops.
The species is black in colour with tiny white spots evenly distributed over the body and fins.
Experts at Planet Catfish claim that the species have been sold under the following L-numbers: L201 (H. contradens); L129 (H. debilittera); L199 (H. furunculus) and L339 (H. lunaorum).
For more information see the paper: Armbruster JW, Lujan NK and DC Taphorn (2007) - Four new Hypancistrus (Siluriformes: Loricariidae) from Amazonas, Venezuela. Copeia, Vol. 2007, Issue 1, pp. 62-79.