Tometes makue (Characidae: Serrasalminae), a new species from Guiana shield, described from the rio Negro Basin (Brazil) and Orinoco Basin (Venezuela)

Abstract

Tometes makue is a new species of Tometes Valenciennes, 1850 from Guiana shield. Previously identified as a Mylesinus species by Kner (1860), Sepulveda (1984) and Jégu et al. (1989), T. makue presents the main characteristics of T. trilobatus Valenciennes, 1850, type species of Tometes, and T. lebaili Jégu et al., 2002. T. makue differs from Mylesinus by stronger and shorter tri- and bicuspid teeth, two last sigmoid premaxillary teeth, a shorter lateral premaxillary processus and the two median lingual teeth bracked together. T. makue differs from T. trilobatus and T. lebaili by a smaller number of prepelvic serrae, which are often absent in the larger specimens (0-9 in adults vs. 11-24 in T. trilobatus and 19-26 in T. lebaili). T. makue differs from T. trilobatus by a greater number of dentary teeth on the labial series (6-11 vs. 5-6 in T. trilobatus). T. makue and T. trilobatus present an horizontal and terminal mouth, whereas it is oblique and upturned in T. lebaili. Juveniles of T. makue present 6 to 10 vertical black stripes on the sides and a humeral black spot between 40 and 85 mm SL. Larger specimens are uniformly grey. Observations on stomach contents indicate that T. makue feed mainly on Podostemaceae. T. makue, which can reach 379 mm SL, is an endemic rheophilic species from Orinoco basin, in Venezuela, and rio Negro basin, in Brazil. T. makue, T. trilobatus, T. lebaili and Mylesinus paraschomburgkii form a group of large phytophagous serrasalmins endemic of the Podostemaceae meadows of Guiana shield, from Caroni river in Venezuela to Maroni river in French Guiana.