Insects of Britain and Ireland: the genera of Lepidoptera-Geometridae
Adults. Crepuscular to nocturnal (attracted to light). Antennae of males bipectinate; apically simple. Face smooth.
Wingspan 29–33 mm. Forewings 1.6–1.7 times as long as wide. The outer margin of the forewing convexly curved. Forewings green; without a clear discal mark. Hindwings conspicuously patterned (with a terminal series of brown or orange-ish, white-bordered crescentic marks, enlarged at apex and tornus); green; predominantly green when fresh; without a clear discal mark; transversely lined (with a dark terminal line).
Vein 10 of the forewings arising out of vein 9. Hindwings exhibiting a tubular vein 5. Vein 5 of the hindwings arising from well above the middle of the transverse vein. Vein 8 of the hindwings shortly anastomosed basally with the upper margin of the cell, thence rapidly diverging. Hindwing veins 6 and 7 stalked.
Posterior tibiae of males 4-spurred.
Early stages. Larvae feeding on foliage of oak, disguising themselves with attached bud scales. Pupae above the ground (in a silken cocoon incorporating leaf fragments, attached to the stem of the foodplant).
British representation. 1 species; South-east England, Central-southern England, South-west England, English Midlands, and Northern England (scarce). Living adults found in July. C. bajularia (Blotched Emerald).
Illustrations. • Geometrinae (‘Emeralds’): Kirby 44 (part). • Geometrinae: Newman (1869).
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’.