| | 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).
Subfamily. Ennominae.
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. 1, Isturgia limbaria (Frosted Yellow); 2, Cepphis advenaria (Little Thorn); 3, Petrophora chlorosata (Brown Silver-line); 4, Plagodis pulveraria (Barred Umber); 5, Plagodis dolabraria (Scorched Wing); 6a, Epione repandaria (Bordered Beauty); 6b-c, Epione vespertaria (male and female Dark Bordered Beauty, = E. repandaria); 7a, Pseudopanthera macularia (Speckled Yellow); 7b, P. macularia variety; 8a-b, Pachycnemia hippocastanaria (Horse Chestnut); 9, Opisthograptis luteolaria (Brimstone). From Newman, 1869.
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, 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. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2003 onwards. Insects of Britain and Ireland: the genera of Lepidoptera-Geometridae. Version: 14th February 2021. delta-intkey.com’.
