Omocestus viridulus (L.) |
Common Green Grasshopper
Order: Orthoptera – grasshoppers, locusts and crickets
British distribution: Throughout most of Britain and in many areas the most common grasshopper, but absent or not recently recorded from much of north and north-west Scotland, and locally absent from some coastal areas of southern England.
World distribution: Widespread in Europe and northern Asia.
|Omocestus viridulus, adult female, Wigtownshire, August 2004.|
Omocestus viridulus is a familiar 'green' grasshopper of a wide range of grassy habitats throughout Britain. Like other members of the order Orthoptera it has:
long, powerful hind legs enabling it to jump.
'leathery', straight-veined fore-wings that protect the delicate, membranous hind-wings.
powerful, biting mouthparts.
ability to 'stridulate' – the action of rubbing two body parts together to produce sound. In the case of the grasshopers (family Acrididae, grasshoppers and locusts), this is done by rubbing the hind legs against the toughened veins of the fore-wings, the inner side of the femur (upper leg) in most species (in the male) having small, peg-like projections for this purpose. The result is a 'chirping' song characteristic for each species. In general, in the grasshoppers, stridulation is done by the male, to attract receptive females, which might reply more quietly.
Immature ('nymph') grasshoppers are smaller, with vestigial wings.
Omocestus viridulus, dorsal view of the same individual as shown in the previous photographs, showing the pronotal keels, angled inwards but not sharply so in this species.
Identification and variation
O. viridulus is one of two widespread and generally common green grasshoppers in grassland, the other being Chorthippus parallelus. However, O. viridulus may be partly or, in the male, entirely brown, while normally brown species such as the common C. brunneus or Myrmeleotettix maculatus may sometimes be green. There is also a female colour variant of O. viridulus with purple along the sides. Attention to detailed characters is required for certain identification; excellent descriptions and illustrations are given in Ragge (1965) and Marshall & Haes (1988). The female has distinctly longer wings than the common form of C. parallelus and has longer and more conspicuous ovipositer valves.
O. viridulus is a species of grassland, particularly where the grass is long or damp, though it is not highly demanding and the photographed individual was in short, dry coastal turf. It is as much a species of upland as of lowland grasslands.
Eggs hatch from April onwards and individuals reach adulthood in mid-June, July or thereafter, giving the species a long season extending into the autumn.
In writing this summary, I have relied heavily on the extensive information provided by Marshall & Haes (1988). Another very useful and readable source is the small booklet by Mahon (1988) and an excellent, comprehensive, but long out of print monograph is that by Ragge (1965).
|• ||Mahon, A., (1988). Grasshoppers and bush-crickets of the British Isles, Shire Publications, Ayelesbury.|
|• ||Marshall, J.A., & Haes, E.C.M., (1988). Grasshoppers and allied insects of Great Britain and Ireland, Harley Books, Colchester.|
|• ||Ragge, D.R., (1965). Grasshoppers, crickets and cochroaches of the British Isles, F. Warne, Wayside & Woodland Series, London.|