SCOTCAT.COM  

Cortés-Hernández, M. Á. et al 2025 (3)

Abstract: A new species of Pimelodella is described from the upper and middle basin of the Orinoco River, upper basin of Negro River, and upper basin of the Apaporis River. The new species is distinguished from its congeners by its unique dark saddle on the predorsal region, and also by its maxillary barbel reaching or slightly exceeding the adipose-fin insertion; anterior margin of pectoral fin-spine with minute straight dentitions covering the middle third of the spine, serrae along its distal third, and posterior margin with 8–10 retrorse dentitions along 40–45% of the middle section of the spine; adipose fin short (23.5–27.2% of SL); caudal fin lobes subequal; 38 total vertebrae; and diffuse dark band along the sub-distal region of the dorsal fin. Polymorphism of fusion pattern of the epiphyseal branches of the supraorbital sensory canals is reported for the new species, and its Negro-Orinoco biogeographic pattern is discussed, (Cortés-Hernández, M. Á. et al 2025). Pimelodella: Adipose fin long, low with a curved margin. The humeral process is long and spiky. Body usually plain with a dark lateral stripe; rather depressed body. Pimelodus: Adipose fin short, high, with a straight or sloping margin. Humeral process broad, triangular. Body variously patterned, usually quite deep, like Synodontis. Aquarium Care: Treat as you would do with any member of the Pimelodella in that they will be predatory on small fishes in the aquarium and it is also better to keep them in small groups rather than singularly, as this will dilute the aggression. Diet: Will eat any aquarium prepared foods such as tablets, pellets, frozen and live foods. Not fussy eaters. Etymology: The specific name nuchalis: From the Latin nuchalis (neck), alluding to the dark saddle on the predorsal region.

None

None

Heptapteridae

South America: Atabapo and Inírida rivers of the upper basin of the Orinoco River, and the Tomo River, a direct tributary of the middle basin of the Orinoco River. Additionally, the new species occurs in the Amazon River basin, in the Guainía River, tributary of the upper basin of the Negro River, and in the Pacoa stream, a tributary of the Apaporis River from the Caquetá River drainage. Type locality: Colombia, Guainía, Río Atabapo, isla Chamochina, border between Colombia and Venezuela, 03°46’57.11”N 67°37’59.1”W.

7.0cm. (2¾ins)

23-26°C (73-79°F)

6.0-7.0.

Cortés-Hernández, M. Á., Conde-Saldaña, C. C., Bermúdez-Casas, K. V., Villa-Navarro, F. A., & DoNascimiento, C. (2025). A long-hidden species of Pimelodella (Siluriformes: Heptapteridae) from the upper and middle Orinoco, and western Amazon tributaries. Neotropical Ichthyology, 23(2), e240112.
Fish in the News 2025.