Author: (Linnaeus, 1758)
Species Overview:
Adult: 10-15 mm wingspan; forewings orange-yellow, suffused with dark reddish-brown, each with a distinctive white triangular mark; hindwings dark grey.
Egg: deposited on the bark of the shoots and small branches of host plants.
Larva: 10 mm long; head yellowish varying to light brown or red-brown, region of stemmata and posterior margin blackish; prothoracic plate black, or dark brown with black posterior and lateral margins; abdomen varying from bright yellow to pale green, integument weakly shagreened, pinacula concolorous; anal comb present; thoracic legs brown.
Pupa: 7-8 mm long; reddish-yellow or dark yellow; cremaster without corners, almost right at the back, eight rather strong cremaster hooks, no anal bristles or hooks; in the larval habitation or in a folded leaf [details pupa A. holmiana ].
Taxonomic Description:
Male:
Acleris holmiana male
Acleris holmiana adult
External characters: 10-15 mm wingspan. Antenna very shortly ciliate; labial palpus yellowish; frons yellowish, rest of head and antenna yellow-brown, rusty or orange-brown; thorax darker; abdomen grey-brown. Forewing slightly expanding terminally; costa curved outwards basally, then slightly arced; apex slightly protruding, pointed; termen slightly sinuate beyond apex, oblique. Ground colour orange-yellow, infused with reddish-brown except at apex and basal area above dorsum, a sprinkling of black scales in tornal and distal areas; a conspicuous triangular, often black-edged, white costal marking beyond middle, markings otherwise poorly defined, pale violet; outer margin of basal fascia slightly oblique, often interrupted at middle; sub-basal fascia from before middle of costa, narrow, weak on dorsum and sometimes with wedge of ground colour; lower half of median fascia extending from white costal marking, sometimes weak internally; pre-apical spot obsolescent, represented by strigulae in terminal area; cilia pale yellow, fuscous around tornus. Hindwing light grey, infuscate terminally (after Bradley et al., 1973; Razowski, 1984).
male genitalia A. holmiana
Genitalia: Tegumen elongate with two lateral, pointed, projections terminally; socii small, protruding posteriorly, with groups of longer hairs anteriorly; arms of gnathos long; tuba analis transparent. Valva elongate, broadest basally; sacculus slender, broad to 1/3, delicately concave in middle ventrally, provided with small termination and single posterior spine; brachiola large, tapering terminally. Aedeagus rather short, heavily sclerotized dorsally, protruding and pointed dorso-terminally; about 20 cornuti present in vesica.
Female:
External characters: Usually slightly larger than male; forewing uniformly broad, colour and markings as in male.
female genitalia A. holmiana
Genitalia: Papillae analis small, sterigma broad with well developed, pointed apically anterior projections; ostium bursae rounded; ductus bursae broad, provided with more strongly sclerotized area posteriorly; signum present, star-shaped.
Biology:
Acleris holmiana is an univoltine species. Adults occur in July and August, frequenting thick hedges of hawthorn and blackthorn and also orchards, gardens and margins of woods. Females deposit the eggs on the bark of the shoots and small branches of host plants. The eggs hatch in the following spring. Larvae feed from May to June, each in a shelter formed from two leaves spun together. Pupation occurs in the larval habitation or in a folded leaf, in June and July (after Bradley et al., 1973).
Host plants:
Crataegus, Rosa, Rubus, Malus, Pyrus, Prunus, Cydonia.
Damage:
Acleris holmiana is an often common but unimportant pest. Larvae cause minor damage to the leaves but infestations on cultivated plants are usually unimportant.
Distribution:
Europe; Asia Minor.
Pheromone:
Pheromone unknown.
Attractantia:
E 11-14Ac (Minks et al., 1977)
or
Z 6-14Ac : 9
E 6-14Ac : 1 (Minks et al., 1977)
or
E 11-14Ac : 9
14Ac : 1 (Frérot et al., 1979b)
Parasitoids:
Ascogaster rufipes Nees (Braconidae)
Rogas circumscriptus Nees (Braconidae)
Hybophanes scabriculus Nees (Ichneumonidae)
Pteromalus dilutipes Ratzeburg (Pteromalidae)