Hello again !
I'm here this time to give some sort of an answer to the question which made me create this thread in the first place. As i can see, I wasn't the first one to ask it, and I won't be the last one either. That's why I wanted to share the result of my researches for some reasonably small predatory fishes. Here we go :
Bony tongues : Pantodon buchholzi (African butterfly fish)
Pikes :
- Pike Characins : Ctenolucius hujeta, Boulangerella maculata
- Pike Minnows : Belonesox belizanus
- Pikeheads : Luciocephalus aura, Luciocephalus pulcher
- Pike Cichlids : Crenicichla regani, Crenicichla compressiceps, Crenicichla zebrina, Crenicichla strigata
Knifefishes : Xenomystus nigri (African knifefish)
Polypteridae :
- Polypterus : Polypterus delhezi, Polypterus palmas palmas, Polypterus senegalus, Polypterus mokelembembe
- Other Polypteridae : Erpetoichthys calabaricus (Ropefish)
Spiny eels :
- Macrognathus genus : Macrognathus meklongensis, Macrognathus aculeatus
- Mastacembelus genus : Mastacembelus caudiocellatus, Mastacembelus albomaculatus, Mastacembelus plagiostomus
Snakeheads : Channa bleheri
Perch-like fishes : Monocirrhus polyacanthus (Amazon leaf fish), Ctenopoma acutirostre (Leopard bush fish), Toxotes jaculatrix (Banded Archerfish)
I hope it will help some people. Feel free to share other ideas if you have some.
Enjoy your monsters !