Insects of Britain and Ireland: the genera of Lepidoptera-Geometridae
Adults. Antennae of males bipectinate; apically simple. Face smooth.
Wingspan 23–26 mm. Forewings 1.4–1.6 times as long as wide. The outer margin of the forewing convexly curved. Forewings green, but rapidly fading to whitish; without a clear discal mark. The outer margin of the hindwings angled. Hindwings plain; green, but rapidly fading to whitish; predominantly green when fresh; without a clear discal mark; transversely lined (with faint first and second lines), or without transverse lines.
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 birch, oak, hawthorn, sallow, etc. Pupae above the ground (in a loose silken cocoon spun amongst the foliage of the food-plant).
British representation. 1 species; South-east England, Central-southern England, South-west England, English Midlands, Northern England, Southern Scotland, Wales, and Ireland (common). Living adults found May and June. J. lactearia (Little Emerald, or Small 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’.