''Allosmerus'' is a

monotypic 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 "unisp ...

genus of

smelt Smelt may refer to: * Smelting, chemical process * The common name of various fish: ** Smelt (fish), a family of small fish, Osmeridae ** Australian smelt in the family Retropinnidae and species ''Retropinna semoni'' ** Big-scale sand smelt ''At ...

. Its sole species, ''Allosmerus elongatus'', the whitebait smelt, is an uncommon Northeast Pacific smelt, about which little is known. Originally described as both ''Osmerus attenuatus'' and ''O. elongatus'', these two species were determined to be

conspecific Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species. Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organism ...

in 1946. The fish can grow from in length, has large eyes, a greenish-gray color on its back, and a silver band along its sides. Unlike most other smelt species which generally have no enlarged teeth in the roof of their mouth, the whitebait has single large tooth in the center of its

vomer The vomer (; ) is one of the unpaired facial bones of the skull. It is located in the midsagittal line, and articulates with the sphenoid, the ethmoid, the left and right palatine bones, and the left and right maxillary bones. The vomer forms ...

, which is sometimes flanked by a smaller tooth on either side. The adult males of the species have a longer

anal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...

. Their

range Range may refer to: Geography * Range (geographic), a chain of hills or mountains; a somewhat linear, complex mountainous or hilly area (cordillera, sierra) ** Mountain range, a group of mountains bordered by lowlands * Range, a term used to i ...

extends from

Vancouver Island Vancouver Island is an island in the northeastern Pacific Ocean and part of the Canadian province of British Columbia. The island is in length, in width at its widest point, and in total area, while are of land. The island is the largest ...

San Francisco, California San Francisco, officially the City and County of San Francisco, is a commercial, Financial District, San Francisco, financial, and Culture of San Francisco, cultural center of Northern California. With a population of 827,526 residents as of ...

, although one fish has been found as far south as

San Pedro, California San Pedro ( ; ) is a neighborhood located within the South Bay (Los Angeles County), South Bay and Los Angeles Harbor Region, Harbor region of the city of Los Angeles, California, United States. Formerly a separate city, it consolidated with Los ...

, a specimen which may have been released as live bait. Often abundant in

bay A bay is a recessed, coastal body of water that directly connects to a larger main body of water, such as an ocean, a lake, or another bay. A large bay is usually called a ''gulf'', ''sea'', ''sound'', or ''bight''. A ''cove'' is a small, ci ...

areas, whitebait are known to spawn on subtidal sandbanks and swim in

schools A school is the educational institution (and, in the case of in-person learning, the building) designed to provide learning environments for the teaching of students, usually under the direction of teachers. Most countries have systems of ...

. The fish has fairly minor economic importance; it serves as food for larger fish, and is netted by some fishermen during the spring and summer to be used as bait.

References

Osmeridae Monotypic ray-finned fish genera Taxa named by Carl Leavitt Hubbs Monotypic marine fish genera Fish described in 1854 {{Osmeriformes-stub