Phalloceros leptokeras, the Sapucaia toothcarp, is a species of poeciliid fish native to Brazil.
Phalloceros leptokeras is found in Brazil in the middle portions of rio ParaÃÂba do Sul drainage.
The females of this species grow to a total length of , while males remain smaller at .
The fish live in tropical freshwater, and are pelagic.
The fish is named in Latin; leptos means "narrow", and keras, "horn", refers to the large, slender sickle-like hook on the gonopodial appendix.