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Sculptures by Phyllis Bone

Order Plecoptera - Stoneflies (Top)

  • Most species have two pairs of membranous wings
  • Hind pair of wings broader than fore
  • Wing veins form double ladder pattern
  • 4mm - 50mm long
  • Reduced, biting mouthparts
  • Soft, flattened bodies
  • Never brightly coloured
  • Often have two long caudal cerci
  • 300 species, more than 150 in Europe
  • World-wide
  • Habitats: rarely far from water, generally on shoreline vegetation and rocks
  • Adults rarely feed, possibly on algae, pollen and lichen, nymphs are phytophagous or carnivorous
O. Plecoptera O. Plecoptera

Adult Plecoptera rarely fly in cold temperatures.

The Plecoptera inspired a recent theory on the origins of insect flight, as the adult wings are rarely used for flight, but are flapped by the adults to skim across the surface of the water. This theory suggests that rowing winglets would have been useful to the insects before they were big enough for flight.

Males attract mates by drumming on the surface of the substrate with the tip of their abdomen.

Order Embioptera - Webspinners, Embiids, Footspinners (Top)

  • Winged and wingless forms
  • Males have 2 pairs of membranous wings
  • 10-12mm long
  • Biting mouthparts
  • Elongate, slender, cylindrical insects
  • Swollen first tarsi on the front legs
  • Enlarged femur on hind legs
  • Eyes kidney-shaped (reniform)
  • 300 species described, none in Britain
  • Mainly tropical, some species in southern Europe
  • Habitat: build silken tunnels in wood and crevices near food sources
  • Feed on dead leaves and animal matter
O. Embioptera

Embioptera are highly evolved for life in their tunnels; their wings can bend at any point, and must be stiffened with blood before flight; their hind legs are muscled to allow rapid running in reverse; their caudal cerci are used as eyes to navigate whilst running at high speed.

Embioptera are the only insects which produce silk as adults, generating it in the glands in their enlarged front tarsi.

Order Orthoptera - Grasshoppers, Locusts, Katydids, Crickets (Top)

  • Two pairs of wings (some species are wingless)
  • Forewings are toughened and narrower than hindwings
  • Forewings vary in size, from being absent to covering abdomen completely
  • Few mm (nymphs) - 255mm long (adults)
  • Biting and chewing mouthparts
  • Enlarged hind legs for jumping
  • 20,000 species, 30 in Britain
  • World-wide
  • Major pests in Africa, the Middle East and west Asia
  • Habitats: desert to caves, in trees and subterranean burrows
  • Scavengers, omnivores, herbivores and carnivores. Carnivores bite humans if disturbed
  • Includes three main families and various smaller families (definite phylogeny is not established)

The Cooloola monster is highly evolved for its burrowing lifestyle, and very unlike most other Orthoptera. When it was discovered in 1976 it was thought to be a hoax, but has now been assigned to its own family- Cooloolidae.

Locusts are large grasshoppers, renowned for their gregarious associations. The biggest swarm ever recorded consisted of 12.5 trillion Rocky Mountain Locusts (Melanophus spretus), which covered an area the size of England, Scotland, Ireland and Wales. Schistocerca gregarius, the desert locust, is the world's most destructive insect. Every day a swarm of 50,000 million desert locusts eats the amount of food needed by 500,000 people for a year.

There are many ways of trying to cope with locust swarms, and some of the less orthodox methods are described by C.V.Riley, e.g. locust soup, locust cake, roasted locust with pepper, locust baked in honey...

Male mole crickets (Gryllotalpus gryllotalpus) (Family Gryllotalpidae) shape their burrow in order to amplify their mating songs, enabling them to be heard up to 1.5km away.

Family Gryllidae

  • Long antennae
  • Globular heads, long cerci, wings fit like a lid
  • Females have needle-like ovipositors
  • Forewings are broader across the top than Tettigoniidae
  • Stridulate by rubbing bases of forewings
  • Ears are found on outer and inner sides of the tibiae
O. Orthoptera Gryllidae O. Orthoptera Gryllidae

Family Tettigoniidae

  • Long antennae
  • Females have blade-like ovipositors
  • Omnivorous and carnivorous
  • Crepuscular and nocturnal
  • Stridulate using wing bases
  • Ears are on the outer sides of the tibiae
O. Orthoptera Tettigoniidae O. Orthoptera Tettigoniidae

Family Acrididae

  • Short antennae
  • Female ovipositors are not elongate
  • Vegetarian
  • Diurnal and crepsucular
  • Stridulate by rubbing hind leg against forewing
  • Ears are along sides of body
O. Orthoptera Acrididae O. Orthoptera Acrididae

Order Phasmida - Stick insects, Leaf insects, Walking sticks (Top)

  • Two pairs of wings but European species wingless
  • Forewings have reduced venation, occasionally mimic leaf venation
  • Body length: few mm - 330mm
    Length including legs can exceed 500mm
  • Chewing mouthparts
  • Superb camouflage as twigs or leaves
  • Stick-like elongate bodies and legs
  • 2,500 species, 4 occur in Britain
  • World-wide, most species in S E Asia
  • Habitat: amongst the foliage in which they are best camouflaged
  • Herbivorous
O. Phasmida O. Phasmida

If attacked, some stick insects will fly away, but most fall to the ground in a cataleptic state. Exceptions to these reactions include hissing, startling the predator by flashing bright wings, or slashing out with the hind legs. The most offensive methods involve secreting or spraying obnoxious materials from repugnatory glands.

Despite its current familiarity, the Indian stick insect, Carauxis morosus, now found in many schools, was undiscovered until 1908.

Order Dermaptera - Earwigs (Top)

  • Two pairs of wings
  • Forewings short, square and veinless
  • Hindwings fanlike
  • 7 - 78mm long
  • Biting mouthparts
  • Posterior abdominal cerci form pincers
  • Adults pale brown to black, temporarily white and cream after moulting
  • Elongate abdomen is uncovered and very flexible
  • 1,800 species, 7 in Britain
  • World-wide, especially tropical
  • Habitats: ground dwelling, in crevices
  • Scavenge plant and animal matter
O. Dermaptera O. Dermaptera

Pincers are used offensively and defensively, helping the wings to open and close, and during copulation.

Male pincers are more strongly curved than nymphal and female pincers

15 exotic earwig species live on bats and rodents.

The German for earwig is ohrwurm - earworm, and the French is perce-oreille - ear piercer, the Old English term was ear-wicga - ear insect. These titles may have arisen when people slept at floor level, and found earwigs searching for dark cavities. Another possible origin is the ear-shaped hind-wing.

The world's largest earwig is the St. Helena Giant Earwig, which can reach up to 7.8cm in length, including pincers of 2.4 cm. This is also the rarest earwig, and is feared to be extinct.

Order Zoraptera (Top)

  • Two pairs of membranous wings, or no wings present
  • Less than 3mm long
  • Very generalised mouthparts for biting
  • Polymorphism within populations: they are either pale, eyeless and wingless, or dark with eyes and wings
  • Distinctive three-segmented thorax with prominent pro-thorax
  • Y-shaped epicranial suture on the head
  • 30 species found to date
  • Ethiopia, the Orient, Pacific regions, Neotropics Nearctic, and New Guinea
  • Habitats: rotting logs, sawdust piles, humus and termites' nests
  • Feed on fungi and small arthropods
O. Zoraptera

Zoraptera were only discovered in 1913.

Found in aggregations, but there is no evidence that they have caste systems.

Order Grylloblattodea - Rock crawlers, Ice-crawlers, Grylloblats (Top)

  • Wingless (adaptation for burrowing)
  • 20 - 35mm long
  • Well-developed biting mouthparts
  • Elongate, cylindrical, soft-bodied
  • Yellow or pale brown
  • Flattened head, eyes small or absent
  • 20 species found to date, none in Britain
  • North America, Siberia, Japan, Korea and China
  • Habitats: cold, wet environments at high altitude, amongst leaf litter and stones, in caves
  • Herbivorous and carnivorous
O. Grylloblattodea

The first gryloblat species, Grylloblatta campodeiformis, was named after the three orders with which it seemed to share features, i.e. cricket (Gryllodea), cockroach (Blattodea) and Diplura (Suborder Campodeida)

The Order Grylloblattodea is the most recent order to have been accepted, and was only established in 1932.

The Mount St. Helens Grylloblat (G. chirugica) is the only known endangered grylloblat species, probably due to its location and man's interference.

Order Dictyoptera - Cockroaches, Mantids (Top)

Suborder Blattodea

  • Two pairs of wings
  • Leathery forewings
  • 10 - 97mm long
  • Biting mouthparts
  • Very broad pronotum
  • Long, spiny legs
  • 3,500 species, 3 native to Britain, 6 introduced
  • World-wide
  • Habitats: desert to semi-aquatic, mainly in humid places, including human dwellings, caves and ants' nests
  • Scavenge most organic matter

O. Dictyoptera Blattodea O. Dictyoptera Blattodea

Suborder Mantodea

  • Two pairs of wings
  • Leathery forewings
  • 10 - 150mm long
  • Biting mouthparts
  • Raptorial, spiny forelegs
  • Mobile, triangular head, long neck
  • 7,000 species, none in Britain
  • Mainly tropical, some species in central and southern Europe
  • Habitats: shrubs, trees and vegetation
  • Prey on other insects, occasionally small reptiles etc.
O. Dictyoptera Mantodea O. Dictyoptera Mantodea

Cucumber skins and bay-leaves are useful cockroach repellents, and the male pheromone is used to attract females to traps.

The fastest cockroach, Periplanta americana, runs upright on its hind legs to achieve a top speed of 1.5m/s.

Females of the larger mantid species often eat the males during mating, using them to nourish the eggs as well as fertilise them.

Order Isoptera - Termites (White ants) (Top)

  • Some have 2 pairs of membranous wings, most are wingless
  • Workers: 2.5mm-15mm long
    Queen up to 140mm long
  • Mandibulate, biting mouthparts
  • 2,300 species, none in Britain
  • Tropical and temperate regions e.g. Africa, Australia. Few species present in Southern Europe
  • Habitats: simplest species live in tunnels in wood, advanced species create termitaria from earth
  • Feed on wood, and also on fungi which is cultivated within the termitaria
O. Isoptera O. Isoptera

Colonies are formed by the flying stages (alates), which lose their wings after only a short flight

Most colonies have a king and queen, as well as many sterile workers and a small proportion of large-jawed soldiers.

Termitaria are highly advanced structures, which provide: insulation against heat, cold and desiccation; convection of air currents; waterproofing; gaseous exchange across the surface; regions for fungal gardens.

The largest termites are the queens of Macrotermes bellicosus, which can reach 14 x 3.5 cm.

Goto Order Plecoptera Goto Order Embioptera Goto Order Orthoptera Goto Order Phasmida Goto Order Dermaptera Goto Order Zoraptera Goto Order Grylloblattodea Goto Order Dictyoptera Goto Order Isoptera