About Rove Beetles

Appearance

A. bilineata adults are glossy black with short, coarse hairs and are about 5-6 mm in length. They have very small, reddish-brown forewings (front wings) with a pair of membranous hindwings folded beneath. The forewings look like pads on the upper abdomen. The long abdomen can appear curved up like a scorpion when the beetles are feeding or disturbed. Well-developed "jaws" cross in front of the head of both adults and larvae. Adults are active, strong fliers.

A. bilineata eggs are oval, about 0.5 mm long and 0.4 mm wide, and are covered with a gelatin-like material which is pale green at first and turns darker after a few days. First instar (smallest) larvae are pale brown, about 1.5 mm long, slender, segmented, and tapered with a large head. The parasitic second and third instar (larger) larvae are white, have simplified legs, and are found within the host puparium.

Biocontrol Description

Many insect pests are preyed upon by adult rove beetles in the soil, and on the surface and folds of plant foliage where they can be ambushed by lurking adults. The adults are predators, while the first instar larvae parasitize maggot puparium for the purpose of overwintering. Rove beetle adults are generalist predators that feed on a variety of insect pests such as; thrips, caterpillars, mealybugs, mites, nematodes, mosquito larvae, aphids, gnats, grubs, and other insects. These predatory beetles are beneficial to farmers and gardeners, because they can reduce pest populations, also referred to as biological control, however, because rove beetles are generalist predators, they can also reduce populations of beneficial insects such as beneficial predatory mite eggs and nymphs.

Rove Beetle Life Cycle