Kryptolebias
Kryptolebias is a genus of killifish in the family Rivulidae mostly native to warm parts of South America but with one species found north through the Caribbean region to the Gulf Coast states of the United States. They are small fish, up to in total length. They are non-annual killifish. The genus was originally named Cryptolebias but this name was pre-occupied by a genus of fossil fish.