The hitch (''Lavinia exilicauda'') is a
cyprinid
Cyprinidae is a family of freshwater fish commonly called the carp or minnow family. It includes the carps, the true minnows, and relatives like the barbs and barbels. Cyprinidae is the largest and most diverse fish family and the largest ver ...
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% of ...
endemic to central
California
California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...
, and was once very common. The common name may derive from a
Pomoan word for this species. It is the only species in the
monospecific genus
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...
''Lavinia''.
Taxonomy
The hitch was first formally
described in 1854 by
Spencer Fullerton Baird and
Charles Frédéric Girard
Charles Frédéric Girard (8 March 1822 – 29 January 1895) was a French biologist specializing in ichthyology and herpetology.
Born in Mulhouse, France, he studied at the College of Neuchâtel, Switzerland, as a student of Louis Agassiz. I ...
with its
type locality given as the
Sacramento River
The Sacramento River ( es, RÃo Sacramento) is the principal river of Northern California in the United States and is the largest river in California. Rising in the Klamath Mountains, the river flows south for before reaching the Sacramento†...
in
California
California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...
.
While the hitch is closely related to the
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. Once considered the sole member of its genus, it has recently been sp ...
(''Hesperoleucus symmetricus''), and the two species can hybridize, leading some authorities to place ''H. symmetricus'' in ''Lavinia'',
genomic data appear to support the fishes' separate lineages.
The ''Lavinia'' genus has been placed in the subfamily
Leuciscinae
Leuciscinae is a subfamily of the freshwater fish family Cyprinidae, which contains the true minnows.
Members of the Old World (OW) clade of minnows within this subfamily are known as European minnows. As the name suggests, most members of the O ...
of 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 ...
Cyprinidae in the 5th edition of ''
Fishes of the World''.
Other authorities classify the Leuciscidae as a family and place the genus ''Lavinia'' in the subfamily
Laviniinae of that family.
Three
distinct population segment {{no footnotes, date=February 2018
A distinct population segment (DPS) is the smallest division of a taxonomic species permitted to be protected under the U.S. Endangered Species Act. ''Species'', as defined in the Act for listing purposes, is a ...
s (DPS)
or subspecies of the hitch are recognized:
*Clear Lake hitch (''chi'' in Pomoan language)
*Monterey hitch (Salinas hitch, Pajaro hitch)
*Sacramento hitch (Central Valley hitch)
These common names or DPS correspond to the subspecies ''Lavinia exilicauda chi'' (Hopkirk, 1974), ''Lavinia exilicauda harengus'' (Girard, 1856) and ''Lavinia exilicauda exilicauda'' (Baird and Girard in Girard, 1854), respectively.
Description
The hitch shape is deep and laterally compressed, with a small head, and a terminal mouth pointing upwards. They are generally silver all over; younger fish have a black spot at the base of the tail, losing it as they age, and becoming generally darker as well. The anal fin is noticeably longer than for other California minnows, with 11-14 rays, while the dorsal fin has 10-13 rays, and is placed further back, the base being positioned between pelvic and anal fins. The tail fin is large and deeply forked. They can get large for minnows, with lengths of up to 36 cm. All of these features make them look much like the
golden shiner
The golden shiner (''Notemigonus crysoleucas'') is a cyprinid fish native to eastern North America. It is the sole member of its genus. Much used as a bait fish, it is probably the most widely pond-cultured fish in the United States. It can be fo ...
. The hitch is closely related to the
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. Once considered the sole member of its genus, it has recently been sp ...
(''Hesperoleucus symmetricus'' complex), and these taxa can hybridize with each other.
[
Hitch are omnivores of the open water, eating a combination of filamentous algae, insects, and ]zooplankton
Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...
. They can be found in lakes, sloughs, and slow-moving sections of rivers and streams. With the highest temperature tolerance among the native fish of the Central Valley, they can be found in both warm and cool water; they also have considerable salt tolerance, for instance occurring in Suisun Marsh
Located in northern California, the Suisun Marsh ( ) has been referred to as the largest brackish water marsh on west coast of the United States of America. The marsh land is part of the San Francisco Bay tidal estuary, and subject to tidal ebb ...
(7-8 ppt salinity), and Salinas River lagoon (9 ppt).
Distribution
Their range includes the Sacramento River
The Sacramento River ( es, RÃo Sacramento) is the principal river of Northern California in the United States and is the largest river in California. Rising in the Klamath Mountains, the river flows south for before reaching the Sacramento†...
-San Joaquin River
The San Joaquin River (; es, RÃo San JoaquÃn) is the longest river of Central California. The long river starts in the high Sierra Nevada, and flows through the rich agricultural region of the northern San Joaquin Valley before reaching Suis ...
System of the Central Valley, the Russian River, Clear Lake, Pajaro River
The Pajaro River (''pájaro'' is ''bird'' in Spanish) is a U.S. river in the Central Coast region of California, forming part of the border between San Benito and Santa Clara Counties, the entire border between San Benito and Santa Cruz Cou ...
, and Salinas River. Although once abundant, but no longer commercially fished in Clear Lake, populations have been declining. The most likely cause appears to be loss of springtime spawning water flows due to water diversion and damming.
Conservation
The Clear Lake hitch was listed as threatened under the California Endangered Species Act
In 1970 California became one of the first states in the U.S. to implement an act that conserves and protects endangered species and their environments. The California Endangered Species Act (CESA) declares that "all native species of fishes, amph ...
in 2014.
Notes
References
* Peter B. Moyle, ''Inland Fishes of California'' (University of California Press, 2002), pp. 136–139
*
{{Taxonbar, from=Q3753948, from2=Q6502713
Lavinia (fish)
Endemic fauna of California
Fish of the Western United States
Freshwater fish of North America
Sacramento River
Salinas River (California)
San Joaquin River
Fish described in 1854
Taxa named by Spencer Fullerton Baird