Pseudancistrus orinoco[2] is a species of catfish in the family Loricariidae.

It is native to South America, where it occurs in the Orinoco basin.

The species reaches 10 cm (3.9 in) in total length.

[3] P. orinoco sometimes appears in the aquarium trade, where it is typically known either as the large-snouted pleco or by its associated L-number, which is L-126.

[4] While initially described as Lithoxancistrus orinoco (a name which is still used for the species by some sources[4][1]), it was reclassified as a member of Pseudancistrus by Jonathan W. Armbruster of Auburn University in 2004.