lyre-tail pleco

This loricariid is distinguished by the absence of an adipose fin, the presence of small plates on the abdominal region, and greatly enlarged pectoral spines. Its body is protected by five rows of keels formed by hypertrophied odontodes, providing it with a robust armor.

Coloration ranges from dark brown to nearly uniform black, devoid of spots or light spots, unlike its sister species Acanthicus adonis. The caudal fin features characteristic stripes of ochre to gray color. The species can reach up to 53.0 cm in standard length (about 60 cm total length).

Geographic variations are noted: specimens from the Orinoco, Rio Branco, and Takutu basins often exhibit darker coloration and a more depressed body than those from other regions.

A benthic species, Acanthicus hystrix frequents the main channels of rivers, in moderate to strong currents. It hides under rock and gravel conglomerates or among medium to large rocky blocks. Omnivorous and detritivorous, it primarily feeds on periphyton colonizing submerged logs along wooded banks.

Mature males exhibit pronounced territorial behavior and can be aggressive in defending their shelters. This aggressiveness suggests limited tolerance among adults in confined spaces, with the species not forming structured shoals but occupying its habitat dispersedly.

Sexual maturity is attained at a significant size, concurrent with the development of hypertrophied odontodes in males. Like its closest congeners, the species is presumed oviparous and cavernicolous, with male likely guarding the spawn within a protected cavity.