Colossoma macropomum (Cuvier, 1818)

Fig. 15

Body deep; greatest depth contained 1.8 to 1.9 and caudal peduncle depth 8.5 to 9.0 times in SL; head length 2.9 to 3.1, predorsal distance 1.5 to 1.7 and caudal peduncle length 8.5 to 9.1 in SL; snout length 3.1 to 3.4, horizontal orbital diameter 5.2 to 5.6 and least interorbital width 1.8 to 2.1 in HL. Mouth terminal; inner row of premaxilla with 2, outer row with 5; inner row of dentary with 3-4, outer with 6 teeth; maxilla toothless. Lateral line complete, with 73-88 pored scales; transverse series above lateral line with 44-50 scale rows and below with 45-50 scale rows. Ventral keel with 42-44 unpaired spines, followed by 6 pairs of spines. Dorsal fin with 14-16, pectoral fin with 12- 15, pelvic fin with 8-9, anal fin with 22-25, and caudal fin with 19 rays (Parron, 2001). Ground color brown, pale- yellowish abdominally; ventral portion of body (except abdomen) covered by large irregular patch of dark-grey pigmentation. Dark-grey fins (Graça, Pavanelli, 2007).

Maximum standard length. 280.0 mm (Graça, Pavanelli, 2007).

Distribution. Río Orinoco and Amazon basins (introduced elsewhere).

Remarks. Colossoma macropomum is a non-native species from the upper rio Paraná and its occurrence can be associated with fish-farming.