| | 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).
Subfamily. Geometrinae.
Illustrations. • Geometrinae (‘Emeralds’): Kirby 44 (part). GEOMETRINAE. 12, Aplasta ononaria (Rest Harrow); 13, Chlorissa viridata (Small Grass Emerald); 14, Pseudoterpna pruinata (Grass Emerald); 15, Geometra papilionaria (Large Emerald); 16, Jodis lactearia (Small Emerald); 17, Comibaena bajularia (Blotched Emerald); 18, Thetidea smaragdaria (Essex Emerald); 19, Hemithea aestivaria (Common Emerald); 20, Thalera fimbrialis (Sussex Emerald); 21, Jodis lactearia (Little Emerald). • Geometrinae: Newman (1869). 1, Aplasta ononaria (The Rest Harrow); 2, Pseudoterpna pruinata (Grass Emerald); 3, Comibaena bajularia (Blotched Emerald); 4, Geometra papilionaria (Large Emerald); 5, Thetidia smaragdaria (Essex Emerald); 6, Jodis lactearia (Little Emerald); 7, Chlorissa viridata (Small Grass Emerald); 8, Hemistola chrysoprasaria (Small Emerald); 9, Hemithea aestivaria (Common Emerald). 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’.
