Astyanax taurorum a new species from dos Touros River, Pelotas River drainage, an upland southern Brazilian river (Characiformes: Characidae)

• Published in: Zoologia (Curitiba, Brazil) Vol. 34; pp. 1 - 8
• Main Authors: de Lucena, Carlos Alberto S., Zaluski, Amanda Bungi, de Lucena, Zilda Margarete Seixas
• Format: Journal Article
• Language: English; Portuguese
• Published: Curitiba Sociedade Brasileira de Zoologia 01.01.2017
• Subjects: Astyanax; Astyanax scabripinnis; Biogeography; Cusps; distribution; Drainage; Evolutionary biology; Fin ray counts; Fins; Fish; Gills; Humerus; Lateral line; Meristic counts; Morphology; New species; Petitions; Phylogenetics; Physical characteristics; Rio Grande do Sul; River basins; Rivers; Taxonomy; Teeth; Uruguay River; Vertebra; ZOOLOGY; Brazil; Rio Grande do Sul Brazil; Argentina; Rio Grande do Sul; Uruguay River; distribution; Taxonomy
• ISSN: 1984-4689; 1984-4670; 1984-4689
• DOI: 10.3897/zoologia.34.e20174

A new species of Astyanax belonging to the Astyanax scabripinnis complex is described from dos Touros River, tributary of the Pelotas River, Uruguay River basin. Astyanax taurorum sp. nov. is distinguished from other species of the Astyanax scabripinnis species complex by having two humeral spots, the first vertically elongated; teeth of inner row of premaxilla with three to five cusps; 2-3 (modes 2 or 3) maxillary teeth; 20-23 (mode 22) branched anal-fin rays; 13-15 (mode 14) gill rakers on lower branch of the first branchial arch; 20-23 (mode 21) total gill rakers in first branchial arch; 33-36 (mode 35) perforated lateral line scales. Astyanax taurorum sp. nov. is similar to Astyanax paris; nevertheless, it can be readily distinguished from it by having a smaller head depth (73.6-83.1% vs. 86.4-95.6%) and smaller interorbital width (24.1-28.0% vs. 30.8-32.8%). In addition, it differs from A. paris by the presence a posttemporal hook-shaped posterodorsal margin.