Insects of Britain and Ireland: the genera of grass moths (Pyralidae-Crambinae and Schoenobiinae)
Adults. Face without a conical hairy prominence. Proboscis functional.
Wingspan 18–27(–29) mm. The fringe glistening-metallic (mostly), or not glistening-metallic (C. perlella). Termen sinuate (mostly), or non-sinuate (C. perlella). Ground colour of the forewings whitish, or ochreous, or brown. Forewings plain, or conspicuously patterned with contrasting colours. The patterning complex, or simple; restricted to longitudinal streaking, or comprising both longitudinal streaking and transverse markings. Forewings without a median line; transversely dark-lined towards the termen (commonly), or not transversely dark-lined towards the termen; the subterminal lines when present, usually conspicuously white-edged; with a strong white median streak (commonly), or without a strong white median streak (the pallid, type form of C. perlella); the median streak when present, interrupted by a cross-bar, or without a cross-bar; variously with a conspicuous white apical mark, or with both a conspicuous white apical mark and a costal one nearby, or without conspicuous white marks at or near the apex (rarely). Forewing vein 7 arising from vein 8. Hindwings whitish, or pale grey to dark grey; plain, or suffused grey.
Distribution and habitats. England, Wales, Scotland, and Ireland. Occurring in coastal locations and inland. In wet places, mesophytic habitats, and dry places. British species: C. ericella, C. hamella, C. lathoniellus, C. leucoschalis, C. pascuella, C. perlella, C. pratella, C. silvella, C. uliginosellus. Adults abroad May to August.
Larvae. Larvae feeding on monocots; Poaceae (mostly), or Cyperaceae (C. silvella on Carex).
General comments. The dark var. warringtonella of the widespread Crambus perlella presumably represents non-industrial melanism. It occurs everywhere with the pale form, but is more frequent in damp locations in the north and west.
Illustrations. • 10 Crambus species, with Catoptria and Platytes: Leech, 1886. • Crambus perlella, with species of Agriphila, Catoptria, Chrysocrambus, Pediasia and Thisanotia: Leech, 1886. • Hübner’s illustrations of 9 Crambus species (1796–1813). • Crambus ericella, C. pratella and C. silvella: Barrett. • Crambus hamella, C. pascuella and C. uliginosellus: Barrett. • Crambus perlella and varieties: Barrett. • Crambus hamella (specimens): photo. • Crambus pascuella (specimen): photo. • Crambus perlella, pale and dark forms (specimens): photo. • Crambus perlella (specimen): photo. • Crambus perlella, melanic var. warringtonella (specimen): photo. • Crambus uliginosellus (specimens): photo. • C. ericella, C. hamella, C. pascuella, C. pratella, C. silvella, C. uliginosellus: forewing patterns.
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 grass moths (Pyralidae-Crambinae and Schoenobiinae). Version: 8th June 2016. delta-intkey.com’.