Hoplias

1. Inferior margins of dentaries almost parallel, in ventral view; tongue without denticles ............................................. ....................................... H. intermedius ( H. lacerdae group)

1’. Inferior margins of dentaries converging towards symphysis; tongue with denticles ......................................... ...................................................... 2 ( H. malabaricus group)

2. Scales on caudal-fin base forming rounded margin ........ 3

2’. Scales on caudal-fin base forming straight margin........ 4

3. Scales on caudal-fin base decreasing abruptely in size.. .......................................................................... H. misionera

3’. Scales on caudal-fin base decreasing gradually in size .......................................................................... Hoplias sp. 2

4. Lateral line, posterior to dorsal-fin origin, with 32 to 34 pored scales.......................................................... H. mbigua

4’. Lateral line, posterior to dorsal-fin origin, with 29 to 31, rarely 32 pored scales................................. Hoplias sp. 3