Lepisosteus (from Greek lepis (), 'scale' and osteon (), 'bone') is a genus of gars in the family Lepisosteidae. It contains four extant species, found throughout eastern and central North America. It is one of two extant gar genera alongside Atractosteus. 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. The longnose gar will migrate upstream to smaller streams with faster-moving water to spawn and lay eggs. 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 <small>Grande, 2010</small>