|
|
|
|
|
|
|
|
|
|
KINGDOM : Animalia
PHYLUM : Arthropoda
CLASS : Insecta
ORDER : Coleoptera
FAMILY :Elateridae
TRIBE :Oxynopterini
GENUS :Oxynopterus
SPECIES :O. Auduoin
Emerald ash borer Buprestidae (PDF) 
|
Insects in the family Elateridae are commonly called click beetles . Other names include elaters, snapping beetles, spring beetles or skipjacks.
Oxynopterus Auduoin, like other members of the genus Oxynopterus, are among the largest of the click beetles. The males have distinctive feather-like antennae, with long flat lamellae extending from the antenna segments. The females in contrast, have thin toothed antennae and are larger than the males. The prothorax is shield-shaped, with sharply pointed posteriolateral tips. The elytra are long and smooth, tapering to a sharp point. The claws are simple, without bristles, pads, or lobes on the tarsal segments. They are predominantly reddish-brown in life.
This family was defined by William Elford Leach 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 all elaterids 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. 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, and 965 valid species in North America.
Some click beetles are large and colorful, but most are under 2 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 downwards and may serve as a terminal proleg in some species. 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, Limonius, Hypnoides and Athous species. 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, 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, corn, and wheat. The subterranean habits of wireworms, their ability to quickly locate food by following carbon dioxide gradients produced by plant material in the soil, and their remarkable ability to recover from illness induced by insecticide exposure (sometimes after many months), make it hard to exterminate them once they have begun to attack a crop.
|