FaunaNet

Dung
Beetles

of eastern NSW




Demarziella sylvestris complex

This is a complex of three species, two found in New South Wales (D. scarpensis and D. sylvestris), which are only distinguishable through examination of the male genitalia. No attempt is made to separate the species using the key.

Distribution
Demarziella scarpensis is known from Barrington Tops to southern Queensland and D. sylvestris is found from the Blue Mountains to south central Queensland.  The first species is restricted to rainforest.  Both species are rarely collected.

Description
Total length 3.6-4.6mm. Dark brown with a slight bronze sheen. Very similar to D. interrupta, differing only in that the 5th, 6th & 7th elytral striae are parallel and not undulate.

Head: Dorsal surface flat, with a few erect bristles. Very densely and coarsely punctate.

Pronotum: Very densely covered with coarse punctures, elongated in depressions. Elevations smooth and shiny. A few coarse bristles.

Pterothorax: Median lobe of metasternum with a low keel, posterior depression shallow or absent, setae absent.

Elytra: Odd-numbered elytral intervals wider than others, with a series of elongated tubercles, except on 1st interval. Tubercles also present on intervals 6 and 8. Each tubercle with one stout bristle on outer edge. Elytral striae parallel, not undulate.

Legs: Inner apical angle of fore tibiae produced into a small rounded process. Outer teeth prominent.

Abdomen: Pygidium densely and coarsely punctate, the basal groove not enlarged.  The male of D. scarpensis has long slightly curved lobes at the apex of the genital tube, whereas the male of D. sylvestris has short strongly curved lobes.

Sexual dimorphism
Female: Fore tibiae with larger outer teeth, inner apical angle rounded, without process, spurs larger. Keel on median lobe of metasternum more prominent. Pygidium less convex.

References
Matthews, E.G. (1976) A revision of the Scarabaeine dung beetles of Australia. III. Tribe Coprini. Aust. J. Zool. Suppl. Ser. 38: 1-52

Matthews, E. G. & Stebnicka, Z. (1986) A review of Demarziella Balthasar, with a transfer from Aphodiinae to Scarabaeinae (Coleoptera: Scarabaeidae) Aust. J. Zool. 34: 449-461