Baryancistrus beggini, new species, is described from the upper Río Orinoco and lower portions of its tributaries, the Río Guaviare in Colombia and Río Ventuari in Venezuela. Baryancistrus beggini is unique within Hypostominae in having a uniformly dark black to brown base color with a blue sheen in life, and the first three to five plates of the midventral series strongly bent, forming a distinctive keel above the pectoral fins along each side of the body. It is further distinguished by having a naked abdomen, two to three symmetrical and ordered predorsal plate rows including the nuchal plate, and the last dorsal-fin ray adnate with adipose fin via a posterior membrane that extends beyond the preadipose plate up to half the length of the adipose-fin spine.
Lujan, N.K., Arce, M. & Armbruster, J.W. 2009. A New Black Baryancistrus with Blue Sheen from the Upper Orinoco (Siluriformes: Loricariidae). Copeia. 2009 (1): 50-56.