[[Apteronotus]] Presently, fifteen species are included in the genus Apteronotus. They can be identified by the following features (Albert, 2001): (1) body surface deep brown or black with a white mid-dorsal stripe and white mental and caudal patches; (2) elongate posterior limb of the anguloarticular; (3) surface of cranial bones solid, not pitted; (4) behavior of inhabiting upland streams, small rivers and lagoons; (5) premaxilla gracile, scroll-shaped in adults, with two or fewer teeth.

Published as part of Carlos David de Santana, 2003, Apteronotus caudimaculosus n. sp. (Gymnotiformes: Apteronotidae), a sexually dimorphic black ghost knifefish from the Pantanal, Western Brazil, with a note on the monophyly of the A. albifrons species complex., pp. 1-11 in Zootaxa 252 on page 1