Insects of Britain and Ireland: butterflies
Adults. Wingspan 46–56 mm; the fringes conspicuously light-and-dark banded. Slender-bodied to medium built; short-bodied. The eyes glabrous. Antennae reaching noticeably over halfway to the wingtip. The antennal clubs abrupt; flattened (blunt, pale-tipped). Labial palps ascending. Having only 4 fully developed legs (forelegs with two tarsal joints and brushlike in males, those of females having 4 tarsal joints with short setae). Fore-legs without a tibial epiphysis. Tibiae of middle legs 2-spurred. Posterior tibiae 2-spurred.
Forewings. Forewings apically blunt. The outer and hind margins angled at about 105 degrees. The outer margins concavely curved; scalloped. Uppersides of the forewings deep orange-brown (tawny); more or less contrastingly dark-veined, or contrastingly dark-veined to not conspicuously dark-veined; without a discal mark; veins, 5 short bars from the costa and numerous discal and sub-terminal spots black.
Hindwings. Hindwings broadly rounded to broadly angular; with the outer margins scalloped. Uppersides of the hindwings tawny orange-brown; more or less conspicuously dark-veined, or conspicuously dark-veined to not dark-veined; conspicuously patterned; without a discal mark; coloured and patterned more or less like the forewings.
Undersides of wings. Undersides of the forewings colour-patterned in pallid representation of the uppersides, save for several silvery-white spots towards the apex; not dark-veined (the venation much less conspicuous than on the upper surface); inconspicuously eye-spotted. The eye-spots 2 (these small and fairly obscure, silver-centred and brownish-orange ringed); posterior towards the apex (borne internally to the conspicuous silver spots near the apex). Undersides of the forewings with several silvery-white subapical spots.
Undersides of the hindwings complexly patterned in yellow-ochreous, mixed reddish, with silvery white blotches and spots on the anterior half, a terminal series of silvery white spots, and a subterminal series of small but conspicuous dark fuscous spots with silvery white centres; not dark-veined (the venation much less conspicuous than on the upper surface); with a subterminal row of spots between the discal spots and the terminal row; conspicuously with silvery-metallic markings; with distinct silvery spots; with the spots of the subterminal row silvery-centred; with several discal silvery spots (some large).
Wing venation. Forewings 12 veined; without basally dilated veins. Forewings with 1 tubular anal vein; the anal veins of the forewings representing 1b only; vein 1b simple. Forewings without a discal cell (no transverse vein between veins 4 and 5). Forewing veins 8 and 9 out of 7, the rest separate.
Hindwings 9 veined; with a praecostal spur; with 2 anal veins; exhibiting vein 1a; the anal veins comprising 1a and 1b. Hindwings with a closed discal cell, or without a closed discal cell; the transverse vein incomplete, or lacking (absent or very faint). 7 veins arising from the hindwing cell. The cell-derived hindwing veins all arising independently of one another, or 3+4 proximally joined (connate only).
Eggs, larvae, pupae. Eggs broadly conical; longitudinally ribbed (with about 40 ribs, their tips forming a small apical corona). The larvae hairy; with rows of bristly spines. I. lathonia on Viola.
Pupae ridged and angular; conspicuously patterned; with shining-metallic markings; exposed, with no coccoon; suspended from the tail (cremaster), with no median silk girdle.
British representation. 2 species (including 1 adventive). Issoria aphrodite (Venus Fritillary, Issoria lathonia (Queen of Spain Fritillary. The adults abroad August to September.
Status in Britain. Rare ocurrence representing occasional, genuine immigrants (I. lathonia, which seemingly may persist as a transient colonist in southeast England), or adventive (I. aphrodite, presumably, it having supposedly occurred in Warwickshire in 1833!).
Distribution. Northern England, English Midlands, East Anglia, Wales, southeast England, central southern England, southwest England, Isle of Wight, and Ireland. Frequenting open places. Habitats calcareous and non-calcareous.
Classification. Superfamily Papilionoidea. Nymphalidae.
Illustrations. • Issoria lathonia (Queen of Spain Fritillary): photos. • Larva and pupa of I. lathonia: Duponchel (1849). • Issoria lathonia (Queen of Spain Fritillary): larva and pupa. • Issoria aphrodite (Venus Fritillary, Aphrodite Fritillary: Morris, 1893).
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’.