Insects of Britain and Ireland: butterflies
Adults. Wingspan 38–45 mm; the fringes conspicuously light-and-dark banded. Slender-bodied to medium built; short-bodied to medium-bodied. The eyes hairy. Antennae reaching about halfway to the wingtips. The antennal clubs abrupt; not flattened. 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 102–105 degrees. The outer margins convexly curved; not scalloped. Uppersides of the forewings orange-brown, or red-orange; contrastingly dark-veined; without a discal mark; blackish basally, and with blackish veins interrupting yellowish transverse bands, subterminal scalloped lines and dots.
Hindwings. Hindwings broadly rounded; not tailed; with the outer margins scalloped (somewhat), or with the outer margins not scalloped. Uppersides of the hindwings orange-brown, or red-orange; conspicuously dark-veined; conspicuously patterned; without a discal mark; the colour patterning more or less resembling that of the forewings, with the blacksh component extending further submedianly and along the inner margin.
Undersides of wings. Undersides of the forewings patterned in very pallid representation of the uppersides, lacking the blackish component; not dark-veined (the venation pattern conspicuous but paler than on the upper surface).
Undersides of the hindwings patterned similarly to the uppersides, but much paler: lacking the blackish basal to submedian component, the most conspicuous features being the pale yellowish spots exhibited basally and in median and terminal rows, and a subterminal row of pale-ringed black spots; not dark-veined (the venation less conspicuous than on the upper surface); without metallic markings.
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 with a discal cell. Forewing veins 8, 9 and 10 out of 7, 11 from the front of the cell.
Hindwings 9 veined; with 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 incomplete (lacking between veins 4 and 5). The cell-derived hindwing veins 3+4 proximally joined (joining where they could be connate had there been a transverse vein!).
Eggs, larvae, pupae. Eggs barrel-shaped to broadly conical (shortly cylindrical, scarcely narrowing above); more or less smooth (below), or longitudinally ribbed (above). The larvae hairy; with rows of bristly spines; exposed feeders. On Succisa pratensis.
Pupae ridged and angular; conspicuously patterned (pale buff, marked with black and orange); without shining-metallic markings; exposed, with no coccoon, or concealed (in drawn-together leaves); suspended from the tail (cremaster), with no median silk girdle.
British representation. 1 species. Euphydryas aurinia (Marsh Fritillary). The adults abroad June.
Status in Britain. Indigenous.
Distribution. Southern Scotland, 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. • Euphydryas aurinia (Marsh Fritillary): photos. • Euphydryas aurinia (Marsh Fritillary): egg, larva, pupa. • The smaller Fritillaries: Newman, 1871.
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’.