Insects of Britain and Ireland: the families of Lepidoptera
Adults diurnal, or crepuscular, or nocturnal; medium sized to large (the flightless females of Orygia about 12–18 mm long); relatively short-bodied (very much so, in Orygia), or medium-bodied, or long-bodied (sometimes hugely); medium built (wingspan more than 8 and less than 15 times the thoracic width) to heavily built (wingspan less than 8 times the thoracic width); with fully developed wings, or wingless, or with vestigial wings (some females); wings in repose packed with the forewings directed backwards to cover hindwings and abdomen.
Antennae very short to of medium length; extending to about 0.28–0.57 times the length of the forewing. Antennae of males bipectinate. Eyes glabrous. Ocelli absent. Chaetosemata absent. Maxillary palps much reduced, or absent; when present, 1 segmented. Labial palps porrect; 3 segmented. Proboscis absent.
Wingspan 25–60 mm; 6–10(–10.5) times the thoracic width. Forewings narrow to broad; 1.5–2.27 times as long as wide. The outer and hind margins angled at 95–105 degrees. The outer margin convexly curved; forewings apically blunt. Hindwings broadly rounded; similar in breadth to the forewings. Hindwing width about 0.9–1 times that of the forewings. Hindwings with a rounded apex; the upper surfaces plain (apart from a sometimes darkened border and marginal dots); with a discal spot, or with a discal spot and with transverse lines, or with neither discal spot nor transverse lines; with a frenulum.
Neuration of forewings and hindwings dissimilar. Forewings 12 veined; with 1 anal vein. The anal veins of the forewings representing 1b only. Forewings lacking a tubular vein 1c. Vein 1b of the forewings simple. The transverse vein complete. Discal cell of the forewings without a tubular media (M) vein. Hindwings 8 veined, or 9 veined; with 2 anal veins. The anal veins of the hindwings comprising 1a and 1b. Hindwings exhibiting vein 1a; lacking a tubular vein 1c. Vein 1b of the hindwings simple. The transverse vein complete to incomplete. The hindwing cell emitting more than six veins, or emitting no more than six veins. 6 veins arising from the hindwing cell (vein 4 sometimes missing), or 7 veins arising from the hindwing cell. The cell-derived hindwing veins all arising independently of one another, or 6+7 proximally joined (these connate to stalked). Vein 8 of the hindwings joined to the cell only by a bar, or anastomosing with the upper margin of the cell (before the middle); not approximating to vein 7.
Fore-legs with a tibial epiphysis (males), or without a tibial epiphysis (females). Tibiae of middle legs 2-spurred. Posterior tibiae 2-spurred (rarely), or 4-spurred (short).
Tympanal organs present; metathoracic.
Eggs, larvae and pupae. Eggs not flattened; smooth or minutely pitted. Larval prolegs 10. Larvae conspicuously, densely long-hairy; with urticating hairs (some being notorious in this connection). On divers dicotyledonous trees and shrubs, and one on Cyperaceae, Sparganium and Phragmites.
Pupae concealed; on the surface of the ground, or above the ground. Empty pupae not becoming protruded.
British representation. Genera 7 (1 extinct); 11 species. Arctornis l-nigrum (Black V Moth - rare adventive), Dicallomera fascelina (Dark Tussock), Calliteara pudibunda (Pale Tussock), Euproctis chrysorrhoea (Brown-tail), Euproctis similis (Yellow-tail), Laelia coenosa (Reed Tussock or Whittlesea Arctia: a victim of draining the fens, and long extinct in Britain), Leucoma salicis (White Satin), Lymantria dispar (The Gypsy), Lymantria monacha (The Black Arches), Orygia antiqua (The Vapourer), Orygia recens (Scarce Vapourer).
Classification. Macromoths. Suborder Ditrysia. Superfamily Noctuoidea.
Comments. Spectacular industrial melanism occurs in British populations of Lymantria monacha (see illustration).
Illustrations. • British Lymantriidae: Newman. • Lymantria dispar (Gypsy) and L. monacha (Black Arches): photos. • Laelia coenosa (Reed Tussock, imago and larva) and Leucoma salicis (White Satin, dissections): B. Ent. 68). • Arctornis L-nigrum (Black V Moth): Stephens II, 1830). • Leucoma salicis (dissections: B. Ent. 68). • Leucoma salicis and Laelia coenosa: B. Ent. 68, legend+text. • Leucoma salicis and Laelia coenosa: B. Ent. 68, text cont.. • Lymantria monacha (Black Arches): B. Ent. 767. • Lymantria monacha: B. Ent. 767, legend+text). • Lymantria monacha: B. Ent. 767, text cont.). • Orgyia recens (Scarce Vapourer: B. Ent. 378). • Orgyia recens: B. Ent. 378, legend+text. • Orgyia recens: B. Ent. 378, text cont.. • Eriogaster, Euthrix, Lymantria and Malacosoma (Humphreys). • Calliteara, Lymantria, Orgyia (and Colocasia, from Humphreys). • Arctornis, Euproctis, Laelia, Leucoma (from Humphreys). • Calliteara, Dicallomera, Orgyia: Kirby). • Arctornis, Euproctis, Leucoma, Lymantria: Kirby. • Larva, pupa, cocoon: Calliteara pudibunda (Duponchel, 1849). • Larva, pupa: Dicallomera fascelina (Duponchel, 1849). • Larvae: Euproctis chrysorrhoea, Euproctis similis (Duponchel, 1849). • Larvae, pupae: Leucoma salicis, Lymantria dispar (Duponchel, 1849). • Larvae, pupae (male and female): Orgyia antiqua, Orgyia recens (Duponchel, 1849). • neuration: Calliteara, Euproctis.
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 families of Lepidoptera. Version: 8th June 2016. delta-intkey.com’.