Insects of Britain and Ireland: orders

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L. Watson and M. J. Dallwitz


Excluding Archaeognatha. Silverfish.

Adult insects. Phytophagous, or saprophagous, or consuming stored produce, or mycophagous (more or less omnivorous, and some secrete their own cellulase). Minute to small; flightless. Body dorsiventrally flattened. Head prognathous to hypognathous (less hypognathous than Archaeognatha). Mouthparts well developed; of the biting type; not piercing; more or less conforming to the generalized biting type (the mandibles biting transversely as in ‘higher’ insects). Antennae conspicuous; simple; 15–35 segmented (‘many-segmented’). Compound eyes vestigial or absent (sometimess represented as isolated omatidia). Ocelli 0, or 1 (reduced). Tarsi 2–5 segmented. Abdomen conspicuously appendaged at the rear (cerci plus appendix dorsalis); with long terminal bristles; with cerci clearly visible at its tip (these long or fairly short, shorter than to sub-equalling the appendix dorsalis, with which they constitute three bristles terminating the abdomen; cf. Ephemeroptera). Abdomen of females with an exserted ovipositor. Abdomen apparently 11 segmented; exhibiting rudimentary abdominal limbs (in the form of reduced ‘abdominal styles’ on some segments).

Larvae. Larvae with three pairs of segmented thoracic legs; without ventral abdominal prolegs. Development of larva into adult gradual; apterygote; not involving a pupal stage.

Classification. Subclass Apterygota.

British representation. Lepismatidae; genera 2; 2 species.

General comments. Very agile runners, nocturnal, omnivorous, often living in association with vertebrates and in human habitations.

Illustrations. • Lepisma - Silverfish (Lubbock 1862). Thysanura (Lepisma saccharina - Silverfish). Archaeognatha (Petrobius maritimus).

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.’.