Insects of Britain and Ireland: orders
~ Dictyoptera-Phasmida. Stick-insects, Leaf-insects.
Adult insects. Phytophagous; mute. Very large (the British introductions about 5–12 cm long, but some tropical forms can exceed 30 cm); flightless (in the the species encountered in Britain). Head prognathous. Mouthparts well developed; of the biting type; conforming to the generalized biting type (with strong, cutting mandibles). Antennae conspicuous; simple; 20–40 segmented (? - many segmented). Ocelli 0 (being present only in some winged forms). Wings two, representing the reduced fore-wings, the hind-wings being absent in British representatives. Tarsi 5 segmented. Abdomen conspicuously appendaged at the rear; with cerci clearly visible at its tip (these fairly conspicuous, but unsegmented); apparently 10 segmented (dorsally, although the first or media segment is between the hind-legs and is ostensibly part of the thorax).
Larvae. Larvae phytophagous. Development of larva into adult not involving a pupal stage.
Classification. Subclass Pterygota; Division Exopterygota.
British representation. Phasmatidae; genera 2; 3 species.
Special features. In Britain, slender and remarkably stick-like in appearance (stick insects).
General comments. This orthopteroid Order is not native to Britain, but several introduced New Zealand species have persisted in warm locations (especially in Cornwall), and the widely cultured laboratory species Carausius morosus occasionally escapes. The Order comprises exclusively foliage feeders, intriguingly stick-like or leaf-like in form. A remarkable capacity for regenerating organs (which sometimes develop in the wrong positions) lends them special interest in morphogenetic studies.
Illustrations. • A South American Stick-insect: Shaw and Nodder (1798). • An apterous American species.
To view the illustrations with detailed captions, go to the interactive key. This also offers full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2003 onwards. Insects of Britain and Ireland: orders. Version: 16th May 2016. delta-intkey.com’.