The rove beetles are a family (Staphylinidae) of beetles, primarily distinguished by their short elytra that leave more than half of their abdomens exposed. With approximately 58,000 species in thousands of genera, the group is currently recognized as the largest family of beetles. It is an ancient group, with fossil rove beetles known from the Triassic, 200 million years ago, and possibly even earlier if the genus Leehermania proves to be a member of this family. They are an ecologically and morphologically diverse group of beetles, and commonly encountered in terrestrial ecosystems.
One well-known species is the Devil's coach horse beetle. For some other species, see List of British rove beetles.
Anatomy
As might be expected for such a large family, there is considerable variation among the species. Sizes range from <1 to 35 mm (1.5 inches), with most in the 2â€"8 mm range, and the form is generally elongate, with some rove beetles being ovoid in shape. Colors range from yellow to reddish-brown to brown to black. The antennae are usually 11 segmented and filiform, with moderate clubbing in some genera. The abdomen may be very long and flexible, and some rove beetles superficially resemble earwigs.
Some members of Paederina, a subtribe of Paederinae, contain a potent vesicant in their haemolymph which can produce a skin irritation called dermatitis linearis. which in English has unfortunately acquired the inaccurate name Paederus dermatitis. The irritant pederin is highly toxic, more potent than cobra venom.
Ecology
Rove beetles are known from every type of habitat that beetles occur in, and their diets include just about everything except the living tissues of higher plants, but now including higher plants with the discovery of the diet of Himalusa thailandensis. Most rove beetles are predators of insects and other kinds of invertebrates, living in forest leaf litter and similar kinds of decaying plant matter. They are also commonly found under stones, and around freshwater margins. Almost 400 species are known to live on ocean shores that are submerged at high tide although these are much fewer than 1% of the worldwide total of Staphylinidae. These include the pictured rove beetle;. Other species have adapted to live as inquilines in ant and termite colonies, and some live in mutualistic relationships with mammals whereby they eat fleas and other parasites, benefiting the host. A few species, notably those of the genus Aleochara, are parasitoids of other insects, particularly of certain fly pupae.
Although rove beetles' appetites for other insects would seem to make them obvious candidates for biological control of pests, and empirically they are believed to be important controls in the wild, experiments using them have not been notably successful. Greater success is seen with those species (genus Aleochara) that are parasitoids.
Rove beetles of the genus Stenus are very interesting insects. They are specialist predators of small invertebrates such as collembola. Their labium can shoot out from the head using blood pressure. The thin rod of the labium ends in a pad of bristly hairs and hooks and between these hairs are small pores that exude an adhesive glue-like substance, which sticks to prey.
Systematics
Classification of the 46,275 (as of 1998) staphylinid species is ongoing and controversial, with some workers proposing an organization of as many as ten separate families, but the current favored system is one of 31 subfamilies, about 100 tribes (some grouped into supertribes), and about 3,200 genera. About 400 new species are being described each year, and some estimates suggest 3/4 of tropical species are as yet undescribed.
References
- Ross H. Arnett, Jr. and Michael C. Thomas, American Beetles (CRC Press, 2001), vol. 1
Important works on Staphylinidae
For the Palaearctic Fauna the most up to date works are:
- Lohse, G.A. (1964) Familie: Staphylinidae. In: Freude, H., Harde, K.W. & Lohse, G.A. (Eds.), Die Käfer Mitteleuropas. Band 4, Staphylinidae I (Micropeplinae bis Tachyporinae). Krefeld: Goecke & Evers Verlag, 264 pp.
- Lohse, G.A. (1974) Familie: Staphylinidae. In: Freude, H., Harde, K.W. & Lohse, G.A. (Eds.), Die Käfer Mitteleuropas. Band 5, Staphylinidae II (Hypocyphtinae und Aleocharinae). Pselaphidae. Krefeld: Goecke & Evers Verlag, 381 pp.
- Lohse, G.A. (1989) Ergänzungen und Berichtigungen zu Freude-Harde-Lohse "Die Käfer Mitteleuropas" Band 5 (1974), pp. 185â€"243 In: Lohse, G.A. & Lucht, W.H. (Eds.), Die Käfer Mitteleuropas. 1. Supplementband mit Katalogteil. Krefeld: Goecke & Evers Verlag, pp. 185â€"243.
Regional works
Europe
- Lott, D.A. (2009). The Staphylinidae (rove beetles) of Britain and Ireland. Part 5: Scaphidiinae, Piestinae, Oxytelinae. Handbooks for the identification of British insects, vol. 12, part 5. St Albans: Royal Entomological Society.British and Irish fauna only
- Tronquet, M. (2006). Catalogue iconographique des Coléoptères des Pyrénées-Orientales. Vol. 1: Staphylinidae. Supplément au Tome XV de la Revue de l’Association Roussillonnaise d’Entomologie. Perpignan: Association Roussillonnaise d’Entomologie.Extensively illustrated
External links
- Digital Library of Early Works on Staphylinidae
- Catalog of the Staphylinidae1758 to the end of the second millennium.[1]
- rove beetles of the world on the UF / IFAS Featured Creatures Web site
- rove beetles of Florida on the UF / IFAS Featured Creatures Web site
