The Cynopoecilus melanotaenia complex is a morphologically homogeneous killifish group, endemic from an area encompassing southern Brazil and northeastern Uruguay. It presently comprises four valid species: C. melanotaenia, the type species of the genus, and C. fulgens, C. intimus, and C. nigrovittatus. 

Brazil: Laguna: Tubarão river floodplains

Cynopoecilus feltrini, n. sp., from the lower Tubarão river basin, southern Brazil, is distinguished from all congeners of the C. melanotaenia complex by having frontal E-scales medially overlapped, branchiostegal region orangish red in males and dorsum with few dark brown spots above opercular region. A phylogenetic tree derived from the analysis of a fragment of the mitochondrial gene cytochrome c oxidase subunit I (681 bp) indicates that C. feltrini is a member of the clade that includes all species of the C. melanotaenia complex except C. melanotaenia, as well as that C. feltrini is the sister group of a clade comprising C. fulgens and C. nigrovittatus.

Most likely not different as for other taxon in the genus.

Max. size cm.
Dorsal ,
Anal ,
D/A ,
LL scale count (average)
Pre- dorsal length to % SL – %
Depth to % SL – %

Costa W.J.E.M., P. F. de Amorim, J.L.O. Mattos, 2016. A new species of inseminating seasonal killifish of the Cynopoecilus melanotaenia complex from southern Brazil (Cyprinodontiformes: Rivulidae) Biodiversity Data Journal 4: e6888

Costa W.J.E.M., 2014. A new genus of miniature cynolebiasine from the Atlantic Forest and alternative biogeographical explanations for seasonal killifish distribution patterns in South America (Cyprinodontiformes: Rivulidae). Vertebrate Zoology 64: 23-33 

Costa W.J.E.M., 1995. Revision of the Neotropical Annual Fish Genus Cynopoecilus (Cyprinodontiformes: Rivulidae). Copeia 1995 (2): 456.