Insects of Britain and Ireland: butterflies
Adults. Wingspan 28–38 mm; the fringes not banded. Medium built; short-bodied. The eyes white-rimmed; notched or emarginate at the bases of the antennae and contiguous with the bases of the antennal sockets; hairy. Antennae reaching noticeably less than halfway to the wingtips to reaching about halfway to the wingtips. The antennal clubs gradual-elongate. Labial palps ascending. Having all 6 legs fully developed and operational for walking. Fore-legs without a tibial epiphysis. Tibiae of middle legs 2-spurred. Posterior tibiae 2-spurred.
Forewings. Forewings apically blunt to pointed. The outer and hind margins angled at about 95–100 degrees. The outer margins convexly curved. Uppersides of the forewings lilac blue (in the male), or blue and fuscous (in the female); without a discal mark; in the male darkened to fuscous only at the termen, in the female fuscous suffused with blue only over the basal half.
Hindwings. Hindwings broadly rounded, or trapezoidal; relatively long- tailed; the tail filamentous and delicate; with the outer margins not scalloped. Uppersides of the hindwings lilac blue (in the male), or blue and fuscous (in the female); fairly conspicuously patterned. Uppersides of the hindwings eye-spotted to not eye-spotted (the subterminal black dots near the tornus being more or less clearly pale-ringed, at least in the female). The eye-spots 1–3; near the tornus. Uppersides of the hindwings without a discal mark; colour-patterned similarly to the forewings, with the addition of a blackish subterminal spot either side of the tail.
Undersides of wings. Undersides of the wings transversely patterned with numerous pale, sinuous lines.
Undersides of the forewings pale brownish, with irregular, partly discontinuous whitish striae. Undersides of the forewings with the ante-medial transverse lines shorter and not extending posteriorly to the discal cell.
Undersides of the hindwings pale brownish, with irregular, partly discontinuous whitish striae, a white posterior fascia, and before the tornus two black, partly orange-edged spots which are marked pale metallic blue-green; with 1–2 black dots within small orange spots near the tornus; eye-spotted. The eye-spots 2; near the tornus. Undersides of the hindwings without a discal mark; with silvery-metallic markings.
Wing venation. Forewings 11 veined. Forewings with 1 tubular anal vein; the anal veins of the forewings representing 1b only; vein 1b simple. Forewings without a discal cell. Forewing vein 5 lacking proximally but present distally from around where one would expect to find the transverse vein, 6 separate, 7 and 8 long-stalked with 8 very short to the costa, 9–11 separate from the cell.
Hindwings 9 veined; without a praecostal spur; with 2 anal veins; exhibiting vein 1a; the anal veins comprising 1a and 1b. Hindwings without a closed discal cell; the transverse vein lacking.
Eggs, larvae, pupae. Eggs discoid (white); densely spinulose. The larvae woodlouse-shaped; associated with ants in the later instars; concealed feeders. On seeds within pods of legumes, and cannibalistic.
Pupae smooth and rounded; conspicuously patterned; exposed, with no coccoon; not suspended, but attached at the tail and secured by a median girdle of silk.
British representation. 1 species. Lampides boeticus (Long-tailed Blue). The adults abroad August and September.
Status in Britain. Rare ocurrence representing occasional, genuine immigrants (a migratory species in mainland Europe, occasionally encountered in southern England.).
Distribution. Southeast England, central southern England, southwest England, and Isle of Wight. Frequenting open places. Habitats calcareous and non-calcareous.
Classification. Superfamily Papilionoidea. Lycaenidae.
Illustrations. • Lampides boeticus (Long-tailed Blue: photos. • Lampides boeticus (Long-tailed Blue): larva and pupa.
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. 2008 onwards. Insects of Britain and Ireland: butterflies. Version: 16th May 2016. delta-intkey.com’.