Wart-biter

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Wart-biter
Adult male of the green morph
Adult male of the green morph
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Orthoptera
Family: Tettigoniidae
Genus: Decticus
Species: D. verrucivorus
Binomial name
Decticus verrucivorus
(Linnaeus, 1758)

The wart-biter (Decticus verrucivorus) is a bush-cricket in the family Tettigoniidae. Its English and scientific names derive from the age-old practice of using the cricket to bite warts from the skin.

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[edit] Description

Adult wart-biters are 31-37 mm long, with females being significantly larger than males. They are typically dark green in colour, usually with dark brown blotches on the pronotum and wings (a dark brown morphotype also occurs). The female has a long and slightly upcurved ovipositor.

The Wart-biter has a song consisting of a rapidly repeated series of short bursts of clicks, sometimes lasting for several minutes.

Wart-biters normally move about by walking; they rarely fly, except when frightened. Most can only fly 3 to 4 meters at a time.

[edit] Habitat

The species is found in calcareous grassland and heathland habitats.

Wart-biters need a mosaic of vegetation, including bare ground/short turf, grass tussocks, and a sward rich in flowering forbs. They prefer areas that are not heavily grazed. The species is thermophilous, and tends to occur on sites with a southerly aspect.

[edit] Diet

The species is omnivorous. Plants eaten include knapweed, nettles, bedstraws; the species also eats insects, including other grasshoppers.

[edit] Life cycle

The wart-biter lays its eggs in the soil; these eggs normally hatch after two winters. It then passes through seven instar stages between April and June. The adult stage is reached in the beginning of July. Wart-biter populations peak in late July and early August.

[edit] Status and distribution

This species occurs throughout continental Europe, except the extreme south, ranging from southern Scandinavia to Spain, Italy, and Greece. It is also found in temperate Asia, as far east as China. Geographic features such as mountains have fragmented the species, leading to a wide range of forms and numerous subspecies.

In Britain, the Wart-biter is confined to five sites, two in East Sussex, and one each in Wiltshire, Dorset and Kent.


[edit] Conservation

The population of wart-biters has declined in many areas of northern Europe. In Britain, it is a highly endangered species; in 1990, some sites had fewer than 100 adults. The species is the subject of a United Kingdom Biodiversity Action Plan.


[edit] References

  • Marshall, Judith A.; E.C.M. Hayes (1988). Grasshopper and allied insects of Great Britain and Ireland. Harley Books. ISBN 0-946589-36-4. 
  • M. J. Samways, K. Harz (May 1982). "Biogeography of Intraspecific Morphological Variation in the Bush Crickets Decticus verrucivorus (L.) and D. albifrons (F.) (Orthoptera: Tettigoniidae)". Journal of Biogeography 9 (3): 243–254. doi:10.2307/2844667. 
  • Dag Øystein Hjermann, Rolf Anker Ims (November 1996). "Landscape Ecology of the Wart-Biter Decticus verrucivorus in a Patchy Landscape". The Journal of Animal Ecology 65 (6): 768–780. doi:10.2307/5675. 
  • AA Cunningham, JM Frank, P Croft, D Clarke, and P Pearce-Kelly Mortality of captive British wartbiter crickets: implications for reintroduction programs Journal of Wildlife Diseases, 33(3), 1997, pp. 673-676

[edit] External links