Abstract
Two new species of Hypostomus Lacépède (Teleostei: Loricariidae) from the rio Paranaíba and rio Grande basins, both in the upper rio Paraná basin, central Brazil, are described herein. One of them is distinguished from all congeners, except H. albopunctatus, by having the pectoral-fin spine length equal to or smaller than the pelvic-fin spine. From H. albopunctatus, it is distinguished by having round dark spots (vs. pale) on body and fins. The second species is distinguished from all congeners, except H. multidens and H. ternetzi, by having more than 115 teeth (vs. less than 109) per ramus on dentary and premaxilla. It is distinguished most readily from H. ternetzi by having teeth with two symmetrical (vs. asymmetrical) cusps. It is distinguished from H. multidens by having round dark spots (vs. pale) over body and fins.
Highlights
Hypostomus occurs widely throughout the neotropics and is one of the most speciose genera among siluriforms, comprising about 117 to 130 species
The upper rio Paraná basin is known as region of endemism for fishes (Britski & Langeani, 1988; Vari, 1988) compared to the remaining portions of the La Plata basin, which includes rio Iguaçu, lower rio Paraná, rio Paraguay, and rio Uruguay basins
Hypostomus denticulatus is distinguished from similar-looking H. ternetzi by having 116-214 teeth per jaw ramus vs. 39-127 teeth per ramus; beige to light-brown body color vs. dark brown; larger orbital diameter, 18.5 to 21.2% of HL (n = 20) vs. 14.5 to 16.1% (n = 20); abdomen naked vs. abdomen partially plated; and teeth with two symmetrical cusps (Fig. 2a) vs. two asymmetrical cusps (Fig. 2b)
Summary
Hypostomus occurs widely throughout the neotropics and is one of the most speciose genera among siluriforms, comprising about 117 to 130 species. The lower count is according to Ferraris (2007) who recognized Aphanotorulus, Isorineloricaria and Squaliforma as valid genera. Ichthyological surveys by the Núcleo de Pesquisas em Limnologia, Ictiologia e Aqüicultura (Nupélia), of the Universidade Estadual de Maringá, jointly with Furnas Centrais Elétricas, provided five years of monthly ichthyological samples from the rio Corumbá basin, a tributary to rio Paranaíba, in Goiás State, central Brazil. These surveys provided enough material to distinguish two new species of Hypostomus. Both are diagnosed from congeners by color, morphometric and meristic traits, and are described
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
