Abstract
The Acanthicus group is allocated in the Ancistrini tribe (Hypostominae, Loricariidae) and is compounded by 13 species in four genera: Acanthicus, Megalancistrus, Pseudacanthicus e Leporacanthicus. The genera Oligancistrus and Spectracanthicus are closely related to the Acanthicus group and have a basal position in relation to the others genera of the group. The taxonomic problems of the …