Acary avion

Acanthicus adonis is among the largest armored catfish species and reaches a length of 1 m (3.3 ft). It is dark brown to black with numerous white spots as a juvenile. As the fish matures, the spots become less numerous and smaller, often disappearing entirely in large adults. Its close relative A. hystrix always lack white spots, regardless of age. In contrast, A. adonis lacks the vermiculated pattern often (but not always) found on the underparts of A. hystrix.

Acanthicus adonis is found in South America where it has been recorded from the Tocantins River basin in Brazil, in the Solimões River at the triple border between Brazil, Colombia and Peru, and in the Yujo River basin, part of the Ucayali River basin, in Peru. This catfish is found in white and clear water rivers where it is a demersal species. These fish are opportunistic omnivores.

Acanthicus adonis is classified in the genus Acanthicus which is derived from the Greek akánthinos, meaning "thorny", alluding to entire upper surface of the head of A. hystrix, the type species, being armed with long erectile odontodes. The specific name, adonis, is from Greek mythology, where Adonis was a handsome young man loved by the goddess Aphrodite, here referring to the attractive spotted juvenile colour pattern.