Author: (Fabricius, 1775)
Notched-winged tortricid
Species Overview:
Adult: wingspan 16-22 mm; mainly brown, with a characteristic emargination on the costa of each forewing. A very variable species.
Larva: up to 15 mm long; head greenish brown or yellowish brown; prothoracic and anal plates light green or yellowish green; abdomen bright green varying to pale green, pinacula concolorous; anal comb with six prongs; thoracic legs light green [Acleris emargana larva].
Pupa: light brown or reddish brown, thorax shining, abdomen dull; in the larval habitation or spun up in fallen leaves or under moss on tree trunks.
Taxonomic Description:
Male:
Acleris emargana adult
Acleris emargana adults 1
Acleris emargana adults 2
External characters: Wingspan 16-22 mm. Labial palpus, head and antenna ochreous to brownish orange; thorax darker, more ochreous posteriorly; abdomen grey to brownish grey. Forewing elongate; costa curved at base, deeply emarginate beyond middle, fringed with long cilia-like scales basally and apically of emargination; apex subfalcate; termen sinuate, oblique. Ground colour yellow-ochreous, strigulated with ferruginous-brown, veins lined with brown or grey-brown, producing a reticulate pattern most pronounced in basal half; markings greyish brown diffusely mixed with ferruginous; basal and sub-basal fasciae represented by striae forming concave transverse lines; inner margin of median fascia sharply defined, fascia diffuse distally, confluent with pre-apical spot which is atrophied and ill-defined, emitting long striae reaching to tornal area; cilia with a plumbeous sub-basal line from below apex, ferruginous terminally from apex to near tornus, grey at tornus. Hindwing light grey, margins narrowly infuscate, strigulated with grey distally; cilia concolorous, with a grey sub-basal line (after Bradley et al., 1973; Razowski, 1984).
male genitalia A. emargana
Genitalia: Tegumen moderate with rounded terminal lobes; socii long and narrow, rounded anteriorly, broader anteriorly than posteriorly; tuba analis strong, rounded and strongly sclerotized in middle terminally. Valva broad basally, tapering terminally, with long costa, thin posteriorly; sacculus strong, rather uniformly broad to three-quarters, with ventral edge curved outwards, concave posteriorly, projecting and provided with group of spines subterminally; termination rather delicate, rounded apically, spined; brachiola rather large. Aedeagus short, with a small sclerite, no cornuti present.
Female:
External characters: Similar to male.
female gen. A. emargana
Genitalia: Papillae analis broad, thin anteriorly; sterigma very broad, protruding in middle posteriorly with broad anterior corners provided with lateral sacs subapically; ostium bursae broad; antrum very short; posterior portion of ductus bursae bulbous, remaining part rather uniformly broad; corpus bursae ovate, minutely spined, chiefly around signum which is rather weak, very often divided into two or three parts.
Variation:
The deep costal emargination characteristic of this species shows considerable variation and it may be relatively shallow in some specimens. The forewing colour varies from unicolorous light ochreous to whitish ochreous or orange-ochreous, the markings being obsolescent. Some specimens are ferruginous-brown without the heavy strigulation or reticulation basally; others are fuscous-grey, heavily strigulated with ferruginous-brown mixed with roughened black scales, the markings obsolescent and reduced to striae and transverse lines, sometimes mixed with raised black scales (after Bradley et al., 1973).
Biology:
According to Razowski, 1984, moths fly from late July until early November, and larvae occur from May till July.
In the UK, moths fly from July to September, frequenting woods, marshes and hedgerows, especially where sallows are well established. Larvae occur from May to July, feeding within folded leaves or spun shoots. Pupation occurs in June and July, in the larval habitation or spun up in fallen leaves or under moss on tree trunks (Bradley et al., 1973).
Host plants:
Betula, Salix, Populus, Alnus, Corylus avellana.
Damage:
Larvae feed within folded leaves or spun shoots. Minor infestations are sometimes noted on nursery trees.
Distribution:
Europe to Siberia, Northern China, Korea (single collection) and Japan. In Tibet, this species is represented by the subspecies Acleris emargana tibetica and in North America, the subspecies Acleris emargana blackmorei Obraztsov occurs.
Pheromone:
Pheromone unknown.
Attractantia:
E 11-14Ac (Weatherston et al., 1974)