Five new species of the Hypostomus cochliodon group (Siluriformes: Loricariidae) from the middle and lower Amazon System

Abstract

Five new species of Hypostomus from the cochliodon group are described from the middle and lower Amazonian Basin. Data for a population of H. hemicochliodon Armbruster, 2003 from Rio Branco (Roraima, Brazil) and comments on the identity of Hypostomus cochliodon Kner, 1854, and on the paraphyly of the group are given. A hypothesis that Hypostomus soniae sp. n. may have been separated from a Paraguayan species during the late Tertiary is advanced. A key for identification for the species of the Hypostomus cochliodon group from Amazon Basin is given.