''Epomis'' is a genus of

ground beetle Ground beetles are a large, cosmopolitan distribution, cosmopolitan family (biology), family of beetles, the Carabidae, with more than 40,000 species worldwide, around 2,000 of which are found in North America and 2,700 in Europe. As of 2015, it i ...

s (Carabidae). The larvae of this genus are notable for being obligate role-reversal predators.

Amphibians Amphibians are four-limbed and ectothermic vertebrates of the class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial, fossorial, arbore ...

such as frogs are normally predators of beetles; however, ''Epomis'' larvae feed exclusively on amphibians.

Description

''Epomis'' beetles are often metallic blue- or green-colored, with a striking yellow-orange rim on the

elytra An elytron (; ; , ) is a modified, hardened forewing of beetles (Coleoptera), though a few of the true bugs (Hemiptera) such as the family Schizopteridae are extremely similar; in true bugs, the forewings are called hemelytra (sometimes alterna ...

and mostly yellow-colored legs and antennae. They are in length.Basilewsky, P. (1955). Révision des epèces africaines du genre Epomis (Carabidae). Transactions of the Royal Entomological Society of London 107: 95-116. They can be distinguished from the closely related genus '' Chlaenius'' by the short (less than three times as long as wide) and triangular labial palps.Trautner Jürgen, & Geigenmüller Katrin (1987). ''Tiger beetles, ground beetles. Illustrated key to the Cicindelidae and Carabidae of Europe.'' TRIOPS Verlag. The larvae reach a body length up to , they are white or yellow colored, with black and orange markings. Like many

larvae, they are elongated with two extensions (urogomphi) at the rear end. They have characteristic double-hooked

mandibles In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower tooth, teeth in place. The mandible sits beneath the maxilla. It is the only movabl ...

. Larvae of the two European species can be distinguished by their color patterns.

Feeding behavior

''Epomis'' larvae hunt in a rare reversal of the usual predator-prey relationship between amphibians and insects. They lure their amphibian predators by making prey-like movements, then evade the predator's attack and disable the predator, often with a bite to the throat or underside. After the attack, the larva stays attached to the amphibian while feeding on it, similarly to external parasites. Adult ''Epomis'' beetles are

generalist A generalist is a person with a wide array of knowledge on a variety of subjects, useful or not. It may also refer to: Occupations * a physician who provides general health care, as opposed to a medical specialist; see also: ** General pract ...

predators but can also feed on amphibians. They sneak up behind their victims, and hold on firmly using their legs. To paralyze the victim, the beetle makes an incision in the pelvic region with its mandibles. The incision apparently cuts leg muscles. The amphibian loses its ability to move and is eaten by the beetle. Scientists speculate that ''Epomis'' evolved this behavior as an aggressive evasion tactic in response to

predation Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...

by amphibians and the success of this tactic led to ''Epomis'' becoming an obligate predator, itself.

Taxonomic status

The genus ''Epomis'' belongs to tribe Chlaeniini in the subfamily

Licininae Licininae is a subfamily of beetles in the family Carabidae, containing the following genera: * '' Acanthoodes'' Basilewsky, 1953 * '' Actodus'' Alluaud, 1915 * '' Acutosternus'' Lecordier & Girard, 1988 * '' Adelopomorpha'' Heller, 1916 * '' An ...

, which consists of species associated with swamps, temporary ponds, and similar types of wetland habitats. It contains about 30 species distributed in the Old World only, with the majority of species occurring in the

Afrotropical The Afrotropical realm is one of Earth's eight biogeographic realms. It includes Africa south of the Sahara Desert, the majority of the Arabian Peninsula, the island of Madagascar, southern Iran and extreme southwestern Pakistan, and the island ...

region. Many taxonomists consider ''Epomis'' as a subgenus of '' Chlaenius'', but differences in larval and adult morphology, as well as the unique life history of ''Epomis'' beetles, support their separate standing as a genus.Pietro Brandmayr, Teresa Bonacci, Tullia Zetto Brandmayr (2010): Larval morphology of epomis circumscriptus (Duftschmid 1812) and of first instar E. dejeani, Dejean, 1831 (Coleoptera, Carabidae, Chlaeniini), with morphofunctional remarks. Zootaxa 2388: 49-58.

List of species

* '' Epomis alluaudi'' Fairmaire, 1901 * '' Epomis amarae'' Andrewes, 1920 * '' Epomis'' ''barkeri'' Csiki, 1931 * '' Epomis bocandei'' (Laferte-Senectere, 1852) * '' Epomis circumscriptus'' Duftschmid, 1812 * '' Epomis croesus'' (Fabricius, 1801) * '' Epomis croyi'' Kirschenhofer, 2003 * '' Epomis daressalaami'' Jedlicka, 1957 * '' Epomis dejeani'' Dejean, 1831 * '' Epomis deplanatus'' (Laferte-Senectere, 1851) * '' Epomis duvaucelii'' (Dejean, 1831) * '' Epomis elisabethanus'' Burgeon, 1935 * '' Epomis elongatus'' (Klug, 1833) * '' Epomis fimbriatus'' (Klug, 1833) * '' Epomis immunitus'' Murray, 1858 * '' Epomis jordani'' (Basilewsky, 1955) * '' Epomis kenyerii'' Kirschenhofer, 2003 * '' Epomis lastii'' Bates, 1886 * '' Epomis latreillei'' (Laferte-Senectere, 1852) * '' Epomis louwerensi'' Andrewes, 1936 * '' Epomis loveridgei'' (Basilewsky, 1951) * '' Epomis nigricans'' Wiedemann, 1821 * '' Epomis nossibianus'' Facchini, 2011 * '' Epomis pharaonis'' Motschulsky, 1865 * '' Epomis protensus'' Chaudoir, 1876 * '' Epomis rhodesianus'' Peringuey, 1899 * '' Epomis simba'' Alluaud, 1929 * '' Epomis tschitscherini'' Jedlicka, 1952 * '' Epomis vientianensis'' Kirschenhofer, 2009 * '' Epomis violaceipennis'' Chaudoir, 1876

References

External links

''Epomis'' Bonelli, 1810
Carabidae of the World {{Taxonbar, from=Q1347509 Licininae Articles containing video clips