Showing posts with label Eyed Elater. Show all posts
Showing posts with label Eyed Elater. Show all posts

Monday, February 15, 2010

Eyed Click Beetle (Alaus oculatus)

OTHER COMMON NAMES:  Eyed Elater, Eastern Eyed Click Beetle.

SIZE:  Around 1 1/2 inches (40mm).

FOOD:  BugGuide says adult beetles may take some nectar and plant juices.  Larvae are predatory.

The larvae of most click beetles are called wireworms.  Several feed on plant roots and can be serious agricultural pests.  However, the Eyed Elater larva is a meat-eater that feeds on many other noxious larvae, including those of wood-boring beetles, flies, and other undesirables. The large larva (up to two inches) has two powerful jaws to aid in disabling and dismembering prey.

LIFE CYCLE:  Eggs are laid in soil.  Larvae are usually found in decaying wood, under logs and other dark, damp places.  The Eyed Elater spends most of its life in the larval form, perhaps as long as 2-5 years.

RANGE:  Widespread in eastern and central North America.  Usually found in deciduous and mixed forest and woodlands.  Adults are attracted to light.

CLICK BEETLE MECHANICS (from the University of Maryland):  "Click beetles have a remarkable spine on the undersurface of the first segment of the thorax. This spine fits into a notch on the second thoracic body segment just between the legs. The spine and notch are part of the engineering that give this beetle its click. The beetle flexes its body in such a way that the spine quickly releases or snaps with a click. When placed on its back, this snap can catapult the beetle in the air. The beetle often lands right side up. If the beetle lands on its back again, the process is quickly repeated until the beetle gets it right."  (Please see the University of Maryland site for photos of the click beetle's spine and notch.)

THE "EYES":  The large "eyes" on the beetle's pronotum are, of course, only eyespots.  They and the other spots on the beetles mottled body are made up of tiny, light-colored scales similar to scales that make up the patterns on a butterfly's wings.  The eyespots are presumed to distract and confuse would be predators.  The Eyed Elator's true eyes are on its head near the base of the antennae. 

Other Sources and Links:
University of Florida 
Texas A and M University




This post is one of many submitted for the debut issue of a new blog carnival dedicated to "the celebration of beetles—of their indescribable beauty, amazing forms, and astonishing diversity."  The name is taken from a quote by British geneticist and noted evolutionary biologist J.B.S. Haldane. When asked by an English cleric what his studies of nature’s diversity had taught him about the Creator, Haldane reportedly quipped, "He has an inordinate fondness for beetles." An Inordinate Fondness was originated by and is hosted this month by Ted MacRae of Beetles in the Bush.  Thank you, Ted!


 


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