Triportheus nematurus
General data
South America: Paraná-Paraguay River basin.
Max length: 18.3 cm SL
Body deep; greatest body depth contained 2.7 to 3.2 and caudal peduncle depth 10.2 to 12.1 times in SL; head length 3.6 to 4.4, predorsal distance 1.6 to 1.8 and caudal peduncle length 9.3 to 14.7 in SL; snout length 3.9 to 5.0, horizontal orbital diameter 3.0 to 3.6 and least interorbital width 2.5 to 3.6 in HL.
Mouth terminal; inner row of premaxilla with 6, outer row with 6 or 7, inner row of dentary with 1, outer row of dentary with 5 or 6 and maxilla up to 2 teeth. First gill arch with 43-48 gill rakers.
Lateral line 33-37 pored scales; transverse series above lateral line with 6 scale rows and below with 2 or 3 scale rows.
Dorsal fin with 11, pectoral fin with 11-13, pelvic fin with 7, anal fin with 28- 34 and caudal fin with 19 rays.
Ground color silvery; longitudinal series of dark-brown spots on flank scales above pectoral-fin origin; black blotch on posterior portion of caudal peduncle, extending to median caudal-fin rays.
