Copris lunaris (Linnaeus, 1758)
Horned Dung Beetle
This is a widespread and generally common species across southern Europe, extending sporadically into central Europe and north into southern Fennoscandia where it is very local and rare, otherwise it occurs from lowland to low mountain altitudes through much of the southern Palaearctic region from Asia Minor and Iran eastwards through southern Siberia to china, it has also become established in Australia following introductions to help dispose of dung produced by introduced cattle. Although it remains generally common in southern and many central European areas there has been a general decline over the north of its range in recent decades. In the UK it was formerly widespread though very local across the south of England from East Anglia to Somerset including the Isle of Wight but suffered a drastic decline during the nineteenth and twentieth century’s, being last recorded in 1974, and is now considered to be regionally extinct. The beetles typically occur in cattle or horse dung on light sandy or chalky soils exposed to the sun, in northern parts of Europe generally on open grazing pasture but in the south it is more eurytopic occurring also in wooded areas and on moors and heaths. Adults are present year round, in northern areas they appear after overwintering in the soil during May and feed for a while before mating occurs on or near the host material. Mated females construct burrows between 10 and 20cm deep beneath or close to larger dung pat, producing a large and conspicuous pile of soil around the entrance, males guard the burrow and form dung into brood masses which are passed to the female within the burrow. Each burrow will contain seven or eight brood mass and each is moulded into shape by the female and then passed into a lateral brood chamber, here she will lay a single egg into each mass and both sexes will guard the tunnel while the larvae develop, any intruding beetles being attacked and driven out of the burrow. The female will remain in the burrow while the larvae develop through the summer, inspecting the brood masses and repairing any damage that might occur in the chambers, and she will only leave when new-generation adults eclose in the summer. Adults may swarm over dung pasture during spring and early summer evenings, flying around dung pats and inspecting them as they do so, and they have been attracted to light in large numbers on the continent. In northern areas peaks of adult abundance occur during April/May and August/September.
This large and convex species displaying pronounced sexual dimorphism might only be confused with the Minotaur beetle Typhaeus typhoeus but here the males have three forward-pointing horns, females lack the cephalic horn and both lack the widely expanded anterior margin of the head seen in the present species. The easiest way to separate them is by the form of the scutellum; in Typhaeus it is large and sinuate laterally, in the present species it is tiny and hardly visible. 16-21mm. Entirely shiny black and glabrous above. Vertex of head convex and smooth, lateral margin obtusely angled and widely expanded in front of the eyes then broadly explanate and rounded anteriorly, rugose and strongly punctured, the margin notched medially. Pronotum transverse and finely bordered, densely and quite strongly punctured throughout. Elytra slightly transverse; each with five well-impressed and impunctate striae that continue into the apical third and often to the apex, and broad, weakly convex interstices. Legs long and very robust. Anterior femora hidden from above, middle and hind femora widely visible, anterior tibiae with four broad external teeth and a long spur at the internal apical angle, middle and hind tibiae broadly expanded towards the apex, each with a single long sharp spur at the inner apical angle. Males have a long and tapering cephalic horn and the anterior margin of the pronotum excavate and produced into short horns laterally. Females have a short and truncate cephalic horn and the pronotum simply raised above a flat anterior margin.