Bembidion is the largest 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 beetles in the family Carabidae by number of species. There have been many attempts to divide it into smaller genera, most notably by René Jeannel

René Jeannel

René Jeannel was a French entomologist. He was director of the Muséum national d'histoire naturelle from 1945-1951. Jeanell's most important work was on the insect fauna of caves in the Pyrenees, France and in the Carpathians, Romania. He also worked in Africa...

 in 1941 and by G.G. Perrault in 1981, but none of them has been generally accepted. All species are small (less than 7.5 mm) and move very fast. Most of them live close to water. The genus has a biantitropical distribution

Biantitropical distribution

Biantitropical distribution refers to the pattern of species that exist at comparable latitudes across the equator but not in the tropics. For example, a species may be found north of the Tropic of Cancer and south of the Tropic of Capricorn, but not in between. This usually has to do with the...

. In warmer regions it is substituted by closely related Tachys and other genera.

This genus is divided into numerus subgenera, some of which are elevated to full genus rank by various authors; as noted above, however, no universally accepted way of splitting the genus exists as of yet. Bembidion subgenera include:

• Bembidion (Bembidion)
• Bembidion (Eurytrachelus) (sometimes in Odontium)
• Bembidion (Notaphus)
• Bembidion (Ocydromus)
• Bembidion (Odontium)