Orcus nummularis(Boisduval)
last updated September 2007

Coccinella nummularis Boisduval, 1835: 594.

The presence of four maculae on each elytron distinguishes this species from the other Australian Orcus.

Length 3.5-4.1 mm.Dorsal surface predominantly metallic brownish; each elytron with 4 yellowish or orange maculae; antennae, labial palp, meso-, and metepimeron, meso-, and metepisternum and abdomen yellowish; rest dark brown. Body rounded, convex. Head micro reticulate between punctures; punctation about as large as eye facets, nearly 1.5 to 2 diameters apart. Eyes with inner margin slightly diverging apically. Antennae 9-segmented; pedicel slightly wider than long; 3rd slightly shorter than pedicel; 9th relatively short, about as long as basal width. Terminal maxillary palpomere with sides nearly parallel; the apex moderately oblique with outer side about 1.5 times as long as inner; terminal labial palpomere slightly elongate; about 2 times longer than basal width; visibly shorter then preceding segment. Pronotal surface sculptured as on head, the sculptures much weaker; punctation about as large as eye facets, as shallow as on head; approximately 1.5 to 2 diameters apart; the punctures not confluent on anterior angles, getting slightly deeper; anterior angles without distinct strigae; lateral borders rounded to slightly truncate; bordering line uninterrupted at base; the line slightly opening anteriorly, then almost reaching lateral border. prosternum short in front of coxae, about 1.5 times longer than prosternal process widest width; hypomeral foveae vestigial; hind tibiae with outer tooth; tarsal claws weakly appendiculate. Elytral surface sculptured as on pronotum; punctation stronger than on pronotum, slightly deeper and more concentrated; about as large as eye facets, approximately 1.5 to 2 diameters apart; lateral margin slightly reflexed, without clear bead; epipleura foveae vestigial. Abdomen with 6 ventrites; 6th fairly evident; surface of ventrite 1 polished between postcoxal lines; postcoxal lines joined at middle, recurving apically without reaching the middle of the segment; apical border of intercoxal process slightly swollen.

Tegmen relatively long, slightly more than 2/3 the abdomen length; penis guide symmetrical, slightly longer than parameres; parameres sparsely setose, the setae short; strut as long as penis guide; penis similar to O. bilunulatus.

Female similar to male, except having only 5 visible abdominal ventrites, the 5th ventrite large and rounded, about 2 times longer than 4th.


distribution map for the speciesDistribution and Biology
This species is easily confused with O. australasiae and some series are mixed. It appears that this species is limited to the south-eastern part of Australia but does not occur in Tasmania.

Species References
Boisduval, J.B.A. 1835. Voyage de Découvertes de l'Astrolabe. Exécuté par ordre du Roi, Pendant les Années 1826-1827-1828-1829, sous le Commandement de M. J. Dumont d'Urville. Faune Entomologique de l'Océan Pacifique, avec l'illustration des Insectes Nouveaux Recueillis Pendant le voyage, Deuxième Partie. Coléoptères et autres ordres. J. Tastu, Paris, viii + 716 pp.

Slipinski, S.A. 2007. Australian Ladybird Beetles (Coleoptera: Coccinellidae) their biology and classification. ABRS, Canberra. 286 pp.

Slipinski, A. and Giorgi, J.A. 2006. Revision of the Australian Coccinellidae (Coccinellidae). Part 6. Tribe Chilocorini. Annales Zoologici (Warszawa), 56(2): 265-304.

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