Lavinia is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of cyprinid

Cyprinid

The family Cyprinidae, from the Ancient Greek kyprînos , consists of the carps, the true minnows, and their relatives . Commonly called the carp family or the minnow family, its members are also known as cyprinids...

 fish

Fish

Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate 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...

 consisting of one or two species native to western North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

.

While there is little doubt as to the membership of the Hitch

Lavinia exilicauda

The hitch Lavinia exilicauda is a cyprinid fish endemic to central California, and once very common. The name is derived from the Pomoan word for this species....

 (L. exilicauda), the position of the closely related California Roach

California roach

The California roach, Hesperoleucus symmetricus, is a cyprinid fish native to western North America and abundant in the intermittent streams throughout central California. It is the sole member of its genus....

 is less clear. While FishBase

FishBase

FishBase is a comprehensive database of information about fish species . It is the largest and most extensively accessed online database on adult finfish on the web...

, ITIS and Taxonomicon all record it as Hesperoleucus symmetricus, Moyle observes that hybrids of the two species are fertile, and that the genetic relationship is also close, and the older genus Lavinia should take precedence.

The origin of the genus name is the mythological Lavinia

Lavinia

In Roman mythology, Lavinia is the daughter of Latinus and Amata and the last wife of Aeneas.Lavinia, the only child of the king and "ripe for marriage", had been courted by many men in Ausonia who hoped to become the king of Latium. Turnus, ruler of the Rutuli, was the most likely of the suitors,...

, although the rationale is unclear.