Cyprinodontiformes

Albornoz-Garzón, Juan G., Conde-Saldaña, Cristhian C., López-Delgado, Edwin O., García-Melo, Jorge E. & Villa-Navarro, Francisco A., 2020, Fishes from the Río Alvarado drainage, Upper Río Magdalena Basin, Colombia, Check List 16 (5), pp. 1181-1198 : 1194-1195

Cyprinodontiformes

1 Pectoral fin with all rays branched; dorsal and anal fins origin posteriorly placed; anal fin in males not modified into a gonopodium ...................... Rivulidae : Rivulus (Cynodonichthys) magdalenae ( Fig. 4G)

1′ Pectoral fin having unbranched rays; dorsal and anal fins placed on middle of body; males with anal fin modified into a gonopodium ................ Poeciliidae : 2

2 Dorsal fin with dark spots; body without dark dots and blotches (in both sexes)... Poecilia sphenops ( Fig. 4H)

2′ Dorsal fin without dark spots; body usually with dark dots and blotches (only in males) ................................ ........................................ Poecilia reticulata ( Fig. 4I)