Insects of Britain and Ireland: the genera of Lepidoptera-Geometridae
Adults. Antennae of males dentate to simple (stout, flatly sub-dentate); shortly, evenly simply-ciliate.
Wingspan 28–32 mm. Forewings relatively narrow-elongate. The outer margin of the forewing convexly curved. Forewings fuscous, sprinkled whitish, with an obscure, dotted, dark postmedian line; with a clear discal mark (this dark fuscous). Forewings of the male without a fovea. Hindwings plain; whitish fuscous, lighter than the forewings; without a clear discal mark; transversely lined to without transverse lines (at most with a very faintly darkened second line).
Hindwings lacking a tubular vein 5. Vein 8 of the hindwings approximated to or anastomosed with the upper margin of the cell to the middle or beyond. Hindwing veins 6 and 7 separate.
Posterior tibiae of males 4-spurred.
Early stages. Larvae feeding on Calluna and Erica.
British representation. 1 species; South-east England, Central-southern England, and South-west England (local). Living adults found in May. Pachycnemia hippocastanaria (The Horse Chestnut).
Illustrations. • Pachycnemia hippocastanaria (The Horse Chestnut): B. Ent. 611. • Pachycnemia hippocastanaria: B. Ent. 611, legend+text. • Pachycnemia hippocastanaria: B. Ent. 611, text cont.. • Cepphis, Epione, Isturgia, Opisthograptis, Pachycnemia, Petrophora, Plagodis, Pseudopanthera: Newman.
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: the genera of Lepidoptera-Geometridae. Version: 8th June 2016. delta-intkey.com’.