Diapoma guarani

Diapoma guarani (Mahnert, Géry, 1987)

Fig. 11

Body elongate; greatest body depth contained 3.2 to 3.4, caudal-peduncle depth 9.9 to 11.3 times in S L; head length 4.5 to 4.6, predorsal length 1.8 to 1.9, and caudal-peduncle length 8.3 to 10.0 in SL; snout length 3.4 to 3.8, horizontal orbital diameter 2.3 to 2.5, and least interorbital width 2.8 to 3.0 times in HL. Mouth terminal; inner and outer row of premaxilla with 3 or 4, dentary with 12-16 and maxilla with 4 or 5 teeth. Lateral line with 6 or 7 pored scales; longitudinal series with 29-31 scales; transverse series above lateral line with 4½ or 5 scales above and below with 4 scale rows. Dorsal fin with 10, pectoral fin with 12-14, pelvic fin with 7 rays, anal with 22-24 rays, and caudal fin with 19 rays. Ground color whitish to pale yellow; darkbrown longitudinal stripe, from pseudotympanum to median caudal-fin rays. Fins overall reddish; distal margin of dorsal, caudal and anal fins black.

Maximum standard length. 48.0 mm.

Distribution. Upper rio Paraná basin, in Argentina, Brazil and Paraguay.

Remarks. Diapoma guarani was identified as Hyphessobrycon sp. by Graça, Pavanelli (2007). Thomaz et al. (2015), in a molecular phylogeny of the Stevardiinae, proposed a new classification where the species of Cyanocharax Malabarba, Weitzman, 2003 and Hyphessobrycon guarani were reallocated to Diapoma Cope, 1894.