Hoplia Illiger, 1803

Sub family: Melolonthinae / Tribe: Hopliini / Genus: Hoplia

Generally small beetles, 5.3-13mm in length. Body colouration greatly varies (dark blacks and browns, through to bright blues, greens, yellows and orange), variable even within species and between males and females. With a metallic sheen.  Dorsal/ventral scales sometimes present, scarce, patterned, or completely covering body. Clypeus subquadrate, labrum distinct, located below clypeus. Antennae 9-10 segmented. Pronotum sometimes with a plain rounded posterior border, sometimes with basomedial emargination around scutellum. Membraneous border present on its anterior margin. Propygidium separated from the 5th abdominal sternite by a suture. Metatibial spurs absent, Metatarsus with a single, simple claw.

The genus Hoplia contains around 295 species. Identifications to species level is extremely troublesome. Most observable morphological features display considerable overlap between species. Male genitalia is also not useable for identification.

Beetles in the genus are readily distinguished from other Melolonthines by the metatarsus with a single claw.

The other significant Genus with Hopliini is Ectinohoplia, containing around 49 species of primarily Oriental distribution. They are separated from Hoplia by their entire propygidium not being covered by the elytra, and having a tuft of bristles at the extremity of the elytral suture.

Also known as the Monkey beetle, some adults of Hoplia are known to feed on leaves of a variety of plants during daytime hours. Others are known to feed on the developing early buds and flowers, causing significant damage to a range of ornamentals, grapes, peaches and almonds.

Larvae of some species are recognised pests, feeding on the roots of turf, ornamentals, trees and shrubs.

The host plants of many species remain unknown.

Hoplia is a widespread genus across Palearctic, Nearctic, Neotropical, Oriental and Southern African biogeographic realms. It is absent from Australia.

UC IPM Pest Note for Hoplia callipyge: http://ipm.ucanr.edu/PMG/PESTNOTES/pn7499.html

Hardy, A.R. 1977 A revision of the Hoplia of the Nearctic Realm (Coleoptera: Scarabaeidae) Occasional Papers in Entomology 23: 48 pp.