FaunaNet

Dung
Beetles

of eastern NSW




Genus Diorygopyx

Species found in eastern New South Wales: D. asciculifer, D. duplodentatus, D. incomptus, D. incrassatus, D. niger, D. tibialis, D. simpliciclunis.

Other species: (Qld): D. cuspidatus

Distribution
Northern New South Wales and southern Queensland.

Description
Medium (5.0-9.5mm), broadly oval, evenly convex. Colour black, surfaces shiny and glabrous, with no tubercles or keels on pronotum or elytra.

2 small clypeal teeth, edge around teeth thickened. Anterior part of underside of pronotum excavated.

Elytra: elytra with 9 striae, of which 7 are dorsal, the other 2 short and at edge of deflexed humeral portion.  Striae indistinct, simple, with very few punctures. Intervals flat. Surface strongly deflexed at humeral angles along the 8th stria, resembling a short pseudepipleuron for anterior third of elytra. Epipleura very narrow, with strongly sinuate margins.

Hind wings: Vestigial in all species except D. tibialis, in which they are only slightly reduced.

Legs: Fore tibiae broadened distally, with 3 small teeth on outer edge, inner edge varying between species and sexes. Middle coxae moderately convergent. Claws large and strongly toothed.

Abdomen: Pygidium finely bordered except at base, which is greatly thickened; disc is strongly convex, glabrous and covered with minute punctures, with a transverse fissure along basal edge which is more or less closed according to species.

Sexual dimorphism
Clypeal teeth of males with 2 apices, one below the other, and the middle of clypeal margin thick; clypeal teeth of females simple and the edge normal. In males, fore tibiae elongated with an irregularly serrated concave inner edge and outer teeth smaller.

Similar Genera
Thyregis, of a similar size and general shape (some species), and with two small clypeal teeth.
Obvious differences: Thyregis with parallel middle coxae, head armament present in males of some species, large teeth on outer edge of tibiae, and claws simple.

Monoplistes, of a similar shape, black and shiny.
Obvious differences: Monoplistes smaller, subdentate claws, with a single very large curved spine on the hind and middle tibiae.

Onthophagus, of a similar size and general shape (some species), black and shiny.
Obvious differences: Onthophagus with no clypeal teeth, outer edge of fore tibiae with 4 teeth, middle coxae parallel.

Ecology
Adults coprophagous, flightless, in tall open forest, closed forest and montane forest.

References
Cassis, G. & Weir, T.A. (1992) Scarabaeinae. pp 106-173. In: Houston, W.W.K. (ed.) Zoological Catalogue of Australia. Coleoptera: Scarabaeoidea. Canberra: AGPS Vol. 9.

Matthews, E.G. (1974) A revision of the Scarabaeine dung beetles of Australia. II. Tribe Scarabaeini. Aust. J. Zool. Suppl. Ser. 24: 1-211.