Insects of Britain and Ireland: the genera of Lepidoptera-Geometridae
Adults. Antennae of males bipectinate; apically simple. Face smooth.
Wingspan 33–35 mm. Forewings 1.5–1.7 times as long as wide. The outer margin of the forewing convexly curved to more or less straight. Forewings green; with a clear discal mark (this white). Hindwings plain; green; predominantly green when fresh; with a clear discal mark (white, proximally paler), or without a clear discal mark; transversely lined (with a white 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 Artemisia, disguising themselves with attached fragments of the food-plant.
British representation. 1 species; South-east England. Living adults found in July. T. smaragdaria maritima (Essex Emerald, subspecies perhaps extinct).
Illustrations. • Geometrinae: Thetidia smaragdaria (Essex Emerald Moth: B. Ent. 300). • Geometrinae: Thetidia smaragdaria: B. Ent. 300, legend+text. • Geometrinae: Thetidia smaragdaria: B. Ent. 300, text cont.. • 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’.