Beneficial insects in the landscape: #52 Eyed Elater (Alaus oculatus)

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	FIGURE 1. The most prominent feature of the Eyed Elater is the two 2 large false eyes (eyespots) on the back of its 1½ inch body. Entomologists assume the eyespots function in a defense mode against would-be predators. The eyespots as well as the other spots are made up of tiny, light-colored scales similar to scales that make up the patterns on a butterfly's wings.


	FIGURE 2. The Eyed Elater's functional eyes are small and rounded, and located on either side of the head just behind its antennae.


	FIGURE 3. The Eyed Elater is a member of the click beetle family—its body is formation is somewhat like a spring-loaded hinge.


	FIGURE 4. The Eyed Elater has a hinged joint between the head and thorax of its body. The hinged joint allows the beetle to arch its back and then quickly snap the hinge, thus propelling the beetle into the air for several inches and allowing it to flip over.

Quick Facts
Common Name:	Eyed Elater
Other Common Names:	Big-eyed Elater and Eyed Click Beetle
Genus / Species:	Alaus oculatus
Size:	Adults 1½ inch; larva up to 2 inches long
Type of Beneficial:	Insect Predator
Type of Metamorphosis:	Immature stages appear different from adults (i.e., complete metamorphosis)
Beneficial Stage(s):	Larval stages are predators
Prey:	Larva are ferocious meat-eaters that dines on many other noxious wood-boring larvae, including those of wood-boring beetles.
Mounted Specimen?	Yes (mounted specimen for viewing available in insect collection at County Extension Office)

If you could flip yourself off your back and hurl four times your body length into the air, would you? If you were a Eyed Elater, of course you would! And you would do it with a very loud "click", because you would want to get away from whatever turned you on your back. Most likely, that culprit would be one of your personal predators and you would want to avoid being its lunch.

As fascinating as this acrobatic trick may be, why would you, as an the adult form of Alaus oculatus, a species of click beetle, be of interest to a gardener? Actually, the adult click beetle isn't of much significance to gardeners, but its larval form, better known as a wireworm, is.

"Wireworm" is the name given to most larvae of the very large click beetle family. Many of these larvae are notorious pests that consume the roots of cereal crops, causing serious damage. Unlike its many cousins, the Eyed Elater larva is ferocious meat-eater that dines on many other noxious larvae, including those of wood-boring beetles, flies, and other undesirables.

Found under logs and other dark, damp places, the Alaus oculatus larva looks like a stocky, yellowish-brown, segmented worm. It has a flat, dark brown rectangular head that ends in 2 powerful jaws. The jaws, which resemble small crab legs, are used to disable and dismember prey. An individual is about 2 inches long. It looks rather dangerous at the posterior end, too. The 10th segment has 2 anal hooks, 10-12 spines, and setae (hairs) in front of the anus. The Eyed Elater spends most of its life in the larval form, perhaps as long as 2-5 years. All the longer to do its good deeds!

The grown beetle is actually rather attractive. It is black, with 2 large false eyes on the back of its 1½ inch body. There is a spine on its poststernum that can be snapped into a corresponding notch on the mesosternum. Then, the beetle flexes its back to "pop" itself as much as 6 inches into the air. It is the release of the spine from the notch that provides the sound effect.

Adults probably feed on nectar, if they feed at all. The only hazard grown critters might present to us is to startle us. They are attracted to light and, in hot weather, may enter a house through an opened window or door at night.

You want to remember the beneficial effect of its offspring before stepping on one. In my mind, it would be more ecologically sound to gently pick the little fellow up and take it back outside, where you could, in the interest of "scientific observation", lay it on its back and watch it hurtle itself through the air.

Beneficials in the Garden & Landscape is an Earth-Kind^TM program coordinated through Extension Horticulture at Texas A&M University. Earth-Kind uses research-proven techniques to provide maximum gardening and landscape enjoyment while preserving and protecting our environment.