Helogenes marmoratus Gunther, 1863
Identification: The possession of nine principal fin rays in the lower lobe of the caudal fin of Helogenes marmoratus distinguished the species from H. gouldingi and H. castaneus, which have eight principal rays on the lower lobe of that fin. The 39-48 anal-fin rays of H. marmoratus separates that species from H. uruyensis, which as 32-37 anal-fin rays. Maximum size: 73 mm SL.
Range: Helogenes marmoratus is known from the Atlantic drainages of Guianas, upper Orinoco and Negro systems and upper Amazon River basin.
Information from Vari, R. P. & H. Ortega. 1986. The catfishes of the Neotropical family Helogenidae (Ostariophysi: Siluroidei). Smithsonian Contributions to Zoology, 442: 1-20.