The species of the Hypostomus cochliodon group (Siluriformes: Loricariidae)

The Hypostomus cochliodon group consists of eight species that were formerly recognized as Cochliodon Kner: H. cochliodon Kner, H. hondae (Regan), H. levis (Pearson), H. oculeus (Fowler), H. plecostomoides (Eigenmann), H. pospisili (Schultz; a synonym of H. hondae ), H. pyrineusi (Miranda-Ribeiro), and H. taphorni (Lilyestrom) and four additional species described herein: H. ericius , H. hemicochliodon, H. pagei, and H. sculpodon . The species occur in four phenetic groups: the intermediate group of H. hemicochliodon and H. sculpodon that appear to be transitional species between other Hypostomus and the H. cochliodon group in terms of diet and tooth shape, a monotypic group containing H. cochliodon , a group characterized by an odontodeless opercle that contains H. ericius, H. levis, H. oculeus , H. pyrineusi , and H. taphorni, and an undifferentiated northern group that contains H. hondae, H. pagei, and H. plecostomoides .