Click beetles Temporal range: | |
---|---|
![]() | |
Click beetle adults and larvae (wireworms) Left: Wheat wireworm ( Agriotes mancus ) Right: Sand wireworm ( Horistonotus uhlerii ) | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Coleoptera |
Suborder: | Polyphaga |
Infraorder: | Elateriformia |
Superfamily: | Elateroidea |
Family: | Elateridae Leach, 1815 |
Subfamilies [1] | |
Agrypninae Contents | |
Synonyms | |
Ampedidae |
Elateridae or click beetles (or "typical click beetles" to distinguish them from the related families Cerophytidae and Eucnemidae, which are also capable of clicking) are a family of beetles. Other names include elaters, snapping beetles, spring beetles or skipjacks. This family was defined by William Elford Leach (1790–1836) in 1815. They are a cosmopolitan beetle family characterized by the unusual click mechanism they possess. There are a few other families of Elateroidea in which a few members have the same mechanism, but most elaterid subfamilies can click. A spine on the prosternum can be snapped into a corresponding notch on the mesosternum, producing a violent "click" that can bounce the beetle into the air. [3] Clicking is mainly used to avoid predation, although it is also useful when the beetle is on its back and needs to right itself. There are about 9300 known species worldwide, [4] and 965 valid species in North America. [5]
Leach took the family name from the genus Elater , coined by Linnaeus in 1758. In Greek, ἐλατήρ means one who drives, pushes, or beats out. [6] It is also the origin of the word "elastic", from the notion of beating out a ductile substance. [7]
Some click beetles are large and colorful, but most are under two centimeters long and brown or black, without markings. The adults are typically nocturnal and phytophagous, but only some are of economic importance. On hot nights they may enter houses, but are not pests there. Click beetle larvae, called wireworms, are usually saprophagous, living on dead organisms, but some species are serious agricultural pests, and others are active predators of other insect larvae. Some elaterid species are bioluminescent in both larval and adult form, such as those of the genus Pyrophorus .
Larvae are elongate, cylindrical or somewhat flattened, with hard bodies, somewhat resembling mealworms. The three pairs of legs on the thoracic segments are short and the last abdominal segment is, as is frequently the case in beetle larvae, directed downward and may serve as a terminal proleg in some species. [8] The ninth segment, the rearmost, is pointed in larvae of Agriotes , Dalopius and Melanotus , but is bifid due to a so-called caudal notch in Selatosomus (formerly Ctenicera), Limonius , Hypnoides and Athous species. [9] The dorsum of the ninth abdominal segment may also have sharp processes, such as in the Oestodini, including the genera Drapetes and Oestodes . Although some species complete their development in one year (e.g. Conoderus ), most wireworms spend three or four years in the soil, feeding on decaying vegetation and the roots of plants, and often causing damage to agricultural crops such as potato, strawberry, maize, and wheat. [10] [11] The subterranean habits of wireworms, their ability to quickly locate food by following carbon dioxide gradients produced by plant material in the soil, [12] and their remarkable ability to recover from illness induced by insecticide exposure (sometimes after many months), [13] make it hard to exterminate them once they have begun to attack a crop. Wireworms can pass easily through the soil on account of their shape and their propensity for following pre-existing burrows, [14] and can travel from plant to plant, thus injuring the roots of multiple plants within a short time. Methods for pest control include crop rotation and clearing the land of insects before sowing.
Other subterranean creatures such as the leatherjacket grub of crane flies which have no legs, and geophilid centipedes, which may have over two hundred, are sometimes confused with the six-legged wireworms. [8]
The oldest known species date to the Triassic, but most are problematic due to only being known from isolated elytra. Many fossil elaterids belong to the extinct subfamily Protagrypninae. [15]
The Elateroidea are a large superfamily of beetles. It contains the familiar click beetles, fireflies, and soldier beetles and their relatives. It consists of about 25,000 species.
Pyrophorus is a genus of click beetle. They are one of several genera in the tribe Pyrophorini, all of which are bioluminescent. Their bioluminescence is similar to that of another group of beetles, the fireflies, although click beetles do not flash, but remain constantly glowing. They have two luminescent spots at the posterior corners of the pronotum, and another brighter light organ on the most-anterior surface of the ventral abdomen. This light organ is even brighter and can only be seen when in flight. Bioluminescent click beetles are found throughout tropical, subtropical and temperate America. Species from Texas, Florida, Puerto Rico, and Cuba are now in different genera in the tribe Pyrophorini, such as Deilelater and Ignelater.
Byrrhoidea is a superfamily of beetles belonging to Elateriformia that includes several families which are either aquatic or associated with a semi-aquatic habitat. Other than the superfamily Hydrophiloidea, most of the remaining Polyphagan beetles which are aquatic are in this superfamily.
The Rhagophthalmidae are a family of beetles within the superfamily Elateroidea. Members of this beetle family have bioluminescent organs on the larvae, and sometimes adults, and are closely related to the Phengodidae, though historically they have been often treated as a subfamily of Lampyridae, or as related to that family. Some recent evidence suggested that they were the sister group to the Phengodidae, and somewhat distantly related to Lampyridae, whose sister taxon was Cantharidae, but more reliable genome-based phylogenetics placed as the sister group to the Lampyridae.
Alaus oculatus, commonly called the eastern eyed click beetle or eyed elater, is a species of click beetle.
Agrypnus murinus is a species of click beetle belonging to the family Elateridae subfamily Agrypninae.
The Omalisinae are a small subfamily of morphologically derived elaterid beetles. The Omalisinae were long considered an independent family in the deprecated family Cantharoidea, and later a family in the Elateroidea, but molecular phylogenies have demonstrated the morphological similarity of Omalisinae to other soft bodied beetles is a case of parallel evolution (homoplasy) of their soft bodies, rather than an apomorphy. Members of this beetle subfamily have been reported to have bioluminescent organs on the larvae, although no recent publications have confirmed this. Some recent evidence indicated they were the sister group to a clade comprising the families Rhagophthalmidae and Phengodidae, however a more comprehensive phylogenetic analysis based on genome sequences strongly supported the Omalisinae as being contained within the Elateridae.
Pyrophorus noctilucus, common name headlight elater, is a species of click beetle.
Drilini is a tribe of beetles known commonly as the false firefly beetles, in the family Elateridae.
Agriotes sputator is a species of click beetle, commonly known as the common click beetle. The adult beetle is brown and inconspicuous, and the larvae live in the soil and are known as wireworms. They are agricultural pests that devour the roots and underground parts of many crops and other plants.
Limonius is a genus of click beetles in the family Elateridae. Many of the species formerly placed in this genus have been removed to other genera such as Gambrinus.
Elaterinae is a subfamily of click beetles in the family Elateridae, containing 12 tribes worldwide.
Agrypninae is a subfamily of click beetles in the family Elateridae. There are at least 130 genera and more than 430 described species in Agrypninae.
Dendrometrinae is a very large subfamily of click beetles in the family Elateridae, containing 10 tribes worldwide, including several formerly recognized subfamily-rank groups such as Athoinae, Crepidomeninae, Denticollinae, Oxynopterinae, Prosterninae, and Semiotinae now all reduced to tribal rank or lower.
The Pyrophorini are a New World taxonomic tribe within the Elateridae subfamily Agrypninae. Pyrophorini is a tribe of bioluminescent beetles, and includes such genera as Pyrophorus and Ignelater.
Sinopyrophorus is a genus of bioluminescent hard-bodied clicking beetles in the superfamily Elateroidea, and is the sole member of the recently recognized family Sinopyrophoridae. The genus currently contains a single species, Sinopyrophorus schimmeli, which was described in 2019 from the subtropical evergreen broadleaf forests of western Yunnan, China.
Oxynopterus mucronatus, sometimes known as the giant click beetle, is a species of click beetle from tropical Southeast Asia. Their larvae are specialized predators of termites.
Ampedus is a genus of click beetles in the family Elateridae. There are currently 461 recognized species of Ampedus beetles. It has a cosmopolitan distribution, but is found mostly in the Holarctic region, primarily in North America, Europe, and Asia. The oldest known fossil from this genus was found in Eocene Baltic amber, estimated to be from 38.0 to 33.9 million years ago.
Dendrometrini is a tribe of click beetles in the family Elateridae, including some formerly recognized subfamily or tribal-rank groups such as Athoinae, Denticollinae, and Hemicrepidiini now all reduced to subtribal rank.
On the University of Florida / Institute of Food and Agricultural Sciences Featured Creatures website: