Insects of Britain and Ireland: orders
Adult insects. Saprophagous and mycophagous, or phytophagous (?). Minute (less than 2 mm long); flightless. Head prognathous. Mouthparts well developed; of the biting type; not piercing; conforming to the generalized biting type (slender and pointed, the maxillary and labial palpi better developed than in other entognathous classes). Antennae absent. Compound eyes vestigial or absent. Ocelli 2. Thoracic legs present (these 5-segmented). Tarsi 1 segmented (with the pretarsus ending in a single claw). Abdomen not conspicuously appendaged; lacking clearly visible cerci; apparently 12 segmented; exhibiting rudimentary abdominal limbs (on segments 1–3).
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 (but sometimes treated as a Class, equivalent in status to the Insecta).
British representation. 3 families in Britain: Eosentomidae, Protentomidae and Acerentomidae; genera 6; 12 species.
General comments. Mostly unpigmented, slow moving. Adult abdomen 12-segmented. In damp places, in soil, leaf litter, moss, under stones, etc.
Illustrations. • Acerentomon doderoi (Silvestri 1907). Acerentomon doderoi. (ventral). (dorsal).
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’.