''Prorivulus auriferus'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% ...

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Rivulidae The Rivulidae are a family of killifishes in the order Cyprinodontiformes. They are commonly known as rivulids, South American killifish or New World killifish. The latter names are slightly misleading, however, as they are neither restricted to ...

. It is only known from a small freshwater creek near the coast in the

Valença, Bahia Valença is a Brazilian city in the state of Bahia and has an estimated population of 97,233. It is visited by tourists because it is the main access to the island of Ilha de Tinharé, famous for the town of Morro de São Paulo. The municipali ...

region in Brazil. This species is the only known member of its

. This small

killifish A killifish is any of various oviparous (egg-laying) cyprinodontiform fish (including families Aplocheilidae, Cyprinodontidae, Fundulidae, Profundulidae and Valenciidae). All together, there are 1,270 species of killifish, the biggest famil ...

is up to about in

standard length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish ...

. Males are overall yellowish, while the smaller females are duller in color.

References

Rivulidae Monotypic fish genera Freshwater fish of Brazil Endemic fish of Brazil {{Cyprinodontiformes-stub