Lepisosteus

Lepisosteus is known to be a freshwater fish. However, they do have the ability to survive in high salinity, and low oxygen water after gulping air. Indeterminate gar remains, most likely of Lepisosteus, from the Palana Formation of India suggest that the genus may have persisted in India up to the Late Paleocene. == Description ==

These fish have ganoid scales on their elongated bodies with a single dorsal fin on the posterior side approximately one inch from their caudal fin. Depending on the clarity of the water, Lepisosteus colors will change. In clear water they can have bright colors of green and silvery-white; alternatively if the water is brackish and cloudy, their colors will be more of a brown hue. Hatchlings are approximately 8–10 mm in size. The average full-grown length of Lepisosteus varies from 34 to 78 inches depending on the species. In comparison to their long snouts, Lepisosteus have relatively small heads; however, their mouths full of sharp teeth. == Life history ==

Lepisosteus is a slow-growing genus generally living a long time. Female gars take 6 years to reach sexual maturity, grow larger, and live up to 22 years. Male gars reach maturity around 3 or 4 years after hatching. The males do not often live longer than 11 years. The longnose gar will migrate upstream to smaller streams with faster-moving water to spawn and lay eggs. Fish of this genus that are newly hatched will attach themselves vertically to submerged objects by an adhesive disc on their snout. The youth stay attached to the objects until the yolk sac is absorbed which usually takes about 9 days. After the yolk sac of an egg is absorbed, the roe hatches. Hatchlings stabilize to a horizontal position, take their first aerial breath, and begin feeding. == Diet ==

Because Lepisosteus has evolved to be a top predator, they are voracious eaters that eat a variety of other freshwater fish and crustaceans such as Ictiobus and blue crabs. Adults will float toward the surface of streams to scout prey that are below them while younger fish in this genus will hide in submersed vegetation to ambush hunt. Studies have found this native North American species is a predator of invasive Asian carp, whose habitat they share. This genus is not generally used for recreational hunting because their roe is toxic to humans. There are no significant threats to these top predators other than habitat loss. On the IUCN Red List of Threatened Species, this genus is listed as Least Concern. ==Taxonomy==

Evolution Phylogenetic evidence suggests that Lepisosteus is ancient genus that diverged from its only extant relative, Atractosteus, during the Early Cretaceous. As with Atractosteus, fossil evidence suggests that the ancestral range of the genus was likely centered around western North America during the Cretaceous and early Paleogene, until major climatic changes led to a shift in range to eastern North America by the late Paleogene. • †Lepisosteus bemisi Grande, 2010 • †"Lepisosteus" indicus (Woodward, 1890) (classification in Lepisosteus uncertain, but most closely related to it) Dubious fossil species • †Lepisosteus aganus (Cope, 1877) Nomen dubium • †Lepisosteus bohemicus (Laube, 1901) Nomen dubium • †Lepisosteus cominatoi Santos, 1984 Nomen dubium • †Lepisosteus cycliferus (Cope, 1873) Nomen dubium • †Lepisosteus fimbriatus Wood, 1846 Nomen dubium • †Lepisosteus glaber Marsh, 1871 Nomen nudum • †Lepisosteus integer (Cope, 1877) Nomen dubium • †Lepisosteus knieskerni Fowler, 1911 Nomen dubium • †Lepisosteus longus Lambe, 1908 Nomen dubium • †Lepisosteus nahunticus (Cope, 1869) Nomen dubium • †Lepisosteus notabilis Leidy, 1873 Nomen dubium • †Lepisosteus occidentalis Leidy, 1856 Nomen dubium • †Lepisosteus opertus Estes, 1964 Nomen dubium • †Lepisosteus strausi Kinkelin, 1884 Nomen dubium • †Lepisosteus suessoniensis Gervais, 1888 Nomen nudum • †Lepisosteus whitneyi Marsh, 1871 Nomen nudum Phylogeny }} == References ==