Blister Beetle

THE FOLLOWING (UNTIL OTHERWISE NOTED) IS FROM:
GERBER, H.S. 1983.
MAJOR INSECT AND ALLIED PESTS OF VEGETABLES IN BRITISH COLUMBIA.
MINISTRY OF AGRICULTURE AND FOOD.

Blister Beetles

Mainly Epicauta oregona Horn
Meloe montanus LeConte

The larvae of some blister beetles feed on grasshopper and cricket eggs Adults feed on all types of foliage. Outbreaks are sporadic.

Vegetables Attacked:

Most vegetables, bean, pea, potato, squash, tomato.

Injury:

The adults feed on foliage; large numbers rapidly defoliate the plants.

Insect:

They are slender, long-legged beetles about 2.5 cm long. The head is set off distinctly from the body and the tip of the abdomen is exposed beyond the squared-off wing covers. They are black, gray, or metallic blue. Some are spotted or striped. Beetles cling tenaciously to the foliage even when disturbed.

Life History:

There is one generation a year. Females lay eggs in the soil. Active larvae feed on the eggs of grasshoppers, crickets, or other ground-nesting insects. Pupation occurs in the spring and adults emerge about June.

Control:

Insecticides should be applied when beetles or damage is first observed.

Sitaris muralis Foerster (currently placed in the genus Apalus) is a meloid beetle.

According to A Field Guide in Colour to Beetles, by KW Harde & PM Hammond (Octopus Books, London, 1984),

"...In central Europe it is rare and can be found only sporadically in the late summer and early autumn. In Britain it has not been seen in recent years, and may now be extinct. The larvae live parasitically with various insects" (p. 222).

J. Cooter (p. 142 in A Coleopterist's Handbook, edn 3, The Amateur Entomologists' Society, Feltham, Middx, UK, 1991) says:

"Apalus muralis was for many years known from an old wall at Cowley, Oxfordshire; the wall is no longer standing and there are only a very small handful of post-war records. It is a parasitoid of Anthophora bees."

EO Essig's old classic textbook College Entomology (Macmillan, N.Y., 1947, pp. 570-571) apparently paraphrases Fabre's account:

"The charming sketch by Fabre (1857) describes the life history of the European Sitaris muralis Foerster, a small black and yellow beetle 8-10 mm. long which develops in nests of bees belonging to the genus Anthophora. The eggs are laid near the ground nests of the bees during late summer and hatch in the fall. The larvae hibernate and become active the following spring, climb the plants to the flowers, and await the visits of the female host bees to which they attach themselves to be carried to the nests being constructed by the bees in the soil. Upon arrival there the triungulins leave the adult bees to seek out their eggs, which are consumed and which enable the predators to transform into apodous eruciform larvae. These latter consume the stored honey, which enables them to develop fully and to transform into prepupae which hibernate the second winter. The following spring pupation takes place and the adult beetles emerge in the summer of the second year preparatory to mating and laying their eggs as indicated above."

Michael K. Oliver