![]() |
Eyed Click Beetle - Alaus oculatus Coleoptera » Polyphaga » Elateroidea (Click, Firefly and Soldier Beetles) » Elateridae (Click Beetles) » Agrypninae Live adult beetles photographed at Vero Beach, Florida, USA. [Cirrus Home] [Beetles Main Page Graphics] [Beetles Alphabetic Table of Contents] |
![]() This eyed click beetle is about 1-1/4 inch long. |
|
The eyed click beetle is found in the southern U.S. as far west as Texas. At up to 2 inches long, it is one of the largest known "click" beetles in the family Elateridae. The huge false eyespots make it readily identifiable; it is thought these startle predators into thinking they are confronting an animal much larger than it really is. The true eyes are located behind the base of the saw-toothed antennae. Most click beetles are considerably smaller and not as conspicuously marked. All click beetles have a defense mechanism responsible for their common name; when disturbed, the beetle launches itself high into the air with an audible click. This feat of strength is accomplished through the use of a stiff chitinous spine on the underside of the prosternum that fits into a groove on the mesosternum; the beetle build pressure against the spine which is suddenly released causing the two segments to spring violently apart. It is said the beetle is able to transition into winged flight during these excursions, but we have never witnessed this phenomenon, and knowing the machinations beetles must undergo to get their flying wings activated, we find it highly unlikely. Indeed, we think the rapid escape mechanism evolved at least in part to compensate for the slow response of the flying equipment. (See figure 2.)
Click beetles undergo complete metamorphosis:
Egg - larvae (beetle larvae are called "grubs") - pupa - adult.
Some species of click beetle have larvae that have a hard shell,
commonly called "wireworms." These grubs can be serious
agricultural pests, feeding as the do on the roots of plants
(corn and other cereal grains are often attacked) during their
1-3 year portion of the life cycle. Wireworm larvae are hard,
smooth, slender, wire-like worms varying from 2 to 1 inches in
length when mature. They are a yellowish-white to a coppery
color with three pairs of small, thin legs behind the head. The
last body segment is forked or notched |
|
|
| References 1. Philip Glogoza, extension entomologist, North Dakota State University Wireworm Management for North Dakota Field Crops (Used with permission) |
|