Author: (Herrich-Schäffer, 1851)
Species Overview:
Adult: 18-22 mm wingspan; forewings greyish-white suffused with greyish-brown and with greyish-brown markings; hindwings grey suffused with brown distally.
Egg: lenticular, flat; yellowish-white turning reddish orange during development.
Larva: full-grown larva ca. 16-18 mm long; body greyish green, pinacula darker; anal comb black, with 5-6 long teeth; prothoracic plate and thoracic legs black; head black with paler adfrontal area.
Taxonomic Description:
Male:
Cnephasia communana male 1
Cnephasia communana male 2
External characters: 18-22 mm wingspan. Antenna very shortly ciliate. Forewing long and narrow; forewing ground colour light grey, diffusely irrorate and suffused with fuscous, sprinkled with black, especially on margins; sub-basal fascia angulate at middle of wing; inner margin of median fascia sinuous, strongly angulate at middle, outer margin diffuse. Hindwing grey, paler basally (Bradley et al., 1973).
male genitalia C. communana
Genitalia: Valva narrow, oblique terminally; sacculus reaching to about two-thirds of the length of valva; uncus long and thin; socii large, narrow; aedeagus slender, curved basally, pointed terminally
Female:
Cnephasia communana female 1
Cnephasia communana female 2
External characters: Forewing slightly broader than in male; forewing markings generally darker.
female genitalia C. communana
Genitalia: Lamella antevaginalis with narrow and elongated lateral parts; antrum broad, sclerotized; ductus bursae short; ductus seminalis situated anteriorly. Signum long.
Variation:
The colouration and markings of the forewing usually show only minor variation. According to Bradley et al., 1973, an extreme form occurs in Surrey (England) in which the ground colour in the basal half of the wing is almost white, the distal half is powdered with whitish grey, and the fasciae are blackish brown and conspicuous.
Biology:
The species is univoltine. Moths are on wing relatively early in the season, from May to June and July. After the eggs are deposited, it takes about 10-15 days before the larvae appear. The young larvae then spin small hibernacular cocoons. Activity is resumed early in the following spring. First-instar larvae mine leaves. Later, larvae feed amongst spun leaves or on flowers. They go through 6 larval stages and are polyphagous.
Host plants:
Chrysanthemum, Helianthus, Plantago, Rumex, Lotus, Vicia faba.
Damage:
Damage to the host plant only becomes apparent during the fifth and sixth larval stages, but is limited because the larvae have then reached the final stage of their development.
The species is an occasional pest of faba bean and is also recorded from sunflower
Distribution:
Europe, North Africa, Asia Minor, Trans-Caucasia and Siberia.
Pheromone:
Pheromone unknown.
Attractantia:
Z 8-12Ac
E 8-12Ac (Frilli, 1974)