Serica MacLeay 1819

Sub family: Melolonthinae / Tribe: Sericini / Genus: Serica

Small, oblong to ovate beetles, body length 5-11mm. Body colouration yellowish brown, reddish brown to blackish and often with an irridescent sheen. Antennae with 8-9 segments, and a 3-segmented club. Labrum attached to apical margin of clypeus, separated by a suture. Highly variable clypeal apex shape, varying between rounded, emarginate, subquadrate or truncate. Frontoclypeal suture distinct, variable in shape. Regularly spaced striation on the elytra present. Metacoxae greatly enlarged. Penultimate ventrite and propygidium separated by a suture. Metatibial apical spurs separated, so that tarsi can move between them.

There are currently around 250 current species in the genus Serica, though that number has been much larger in the past.  

Examination of the male genitalia is often required for species level identification in areas of high diversity, and little information is available for most species.

They are a member of the Sericini tribe which share the following attributes:

Generally small sized with a convex body shape. Labrum indistinct, attached to the front margin of the clypeus. Metacoxae large, projecting forward where metasternum would usually be, and commonly covering first two abdominal sternites. Widely separated mesocoxae. Metatibial spurs widely separated, so that the tarsi can pass between them.

A key to Australian Sericini can be found in Britton (1957).  A key to North American genera is provided by Ratcliffe, Jameson and Smith (2002).

Other members of Sericini dealt with in the key are the widely occuring Serica, and the native Australian Phyllotocus. Serica can be separated from these genera by having 8-9 antennal segments (Maladera castanea 10, Phyllotocus 8). Tarsal claws of Phyllotocus are simple, whereas they are bifid in Serica and with a median tooth in Maladera castanea.

Little information is known about the biology of most species. Adult beetles are leaf feeders, most commonly on deciduous trees. Most species are nocturnal and attracted to lights, though diurnal species also exist. Larvae are root feeders.

The genus is widespread, with representatives found in the Palearctic, Nearctic, Oriental, and Ethiopian regions. It is absent from Australia.

Britton, E.B. 1957. A Revision of the Australian Chafers (Coleoptera: Scarabaeidae: Melolonthinae). London : British Museum Vol. 1 vii 185 pp.

Ratcliffe, B.C., Jameson, M.L., Smith, A.B.T. . 2002. Chapter 34. Scarabaeidae Latreille1802, pp. 39–81 (in part). In: Arnett, R. H., M. C. Thomas, P. E. Skelley, and J. H. Frank (eds.), American Beetles, Volume 2. CRC Press, Boca Raton, FL. 861 pp.

Ratcliffe, B.C., Paulsen, M.J. 2008. The Scarab Beetles of Nebraska. Bulletin of the University of Nebraska, Vol. 22. 570pp.