Taxonomic revision of the genus Anostomoides (Characiformes: Anostomidae) Author Assega, Fernando Massayuki Author Birindelli, José Luís Olivan text Zootaxa 2019 2019-07-23 4646 1 124 144 journal article 26149 10.11646/zootaxa.4646.1.7 5a6ece22-47cb-49ec-b8c2-5b3f370ac6de 1175-5326 3346413 115C2766-5709-4903-BCFE-A3613891C2EB Genus Anostomoides Pellegrin Anostomoides Pellegrin 1909: 346 . Type species: Anostomoides atrianalis Pellegrin 1909 . Type by monotypy. Gender: masculine. Diagnosis. The genus Anostomoides is diagnosed among Anostomidae by having the following combination of non-exclusive features: mouth upturned or slightly upturned with four teeth on premaxillary ( Fig. 2 ), including symphyseal tooth unicuspid or bicuspid (never tricuspid), remaining teeth slightly tricuspid (with medial cuspid distinctly larger); four dentary teeth, symphyseal tooth with truncate cutting edge (without cusps); second tooth unicuspid, and two lateral teeth with small cusps (three or slightly more cusps) ( Fig. 3 ); lower jaw lip with dermal papillae either rounded or forming ridges. See Discussion for comparisons with other genera. Distribution. The species of Anostomoides are distributed in the Amazon, Essequibo , and Orinoco basins and their tributaries, in Brazil , Bolivia , Colombia , Guyana , Peru , and Venezuela .