Acleris comariana

Author: (Lienig and Zeller, 1846)

Strawberry tortrix moth

Species Overview:

Adult: 12-18 mm wingspan; forewing ground colour extremely variable, sometimes with blackish scale tufts and often with a conspicuous costal blotch; hindwings grey. A very variable species.
Egg: 0.8 x 0.6 mm; flat and oval, chorion sculptured; silver-white, whitish green or pale yellow, the general colouration varying according to the season; eggs which overwinter become brick red, those from the early summer generation change very little in colour; deposited singly, on the underside of mature leaves of the food plant.
Larva: head yellow or yellowish brown, region of stemmata and postero-lateral margin marked with blackish; prothoracic plate yellowish brown, posterior margin dark brown or black; abdomen varying in colour from whitish green to yellowish green, yellowish brown or dull green, with indistinct darker subdorsal line; pinacula brown; thoracic legs yellowish brown. In early instar larvae the head and prothoracic plate are entirely black, the abdomen is paler in colour and the thoracic legs are blackish brown. The larva may be distinguished from that of Acleris laterana by the blackish brown posterior margin of the prothoracic plate which in Acleris laterana is marked with a well-defined dark subdorsal spot on either side, and by the brown pinacula which in Acleris laterana are concolorous with the integument [Acleris comariana larva].
Pupa: 8-10 mm long, reddish or pale brown, wings, thorax and head with tinge of green; cremaster short and broad, end of cremaster with two sharp corners behind, four slender cremaster hooks and four slender anal hooks; in a silken cocoon in the larval habitation [Acleris comariana pupa ; details pupa Acleris spp.].

Taxonomic Description:

Male:

Acleris comariana adult
Acleris comariana adults 1
Acleris comariana adults 2
External characters: 12-18 mm wingspan. Labial palpus ochreous-grey to brownish; head yellow-brown to reddish brown, thorax brownish-grey to reddish-brown, sometimes with an olive-green hue, abdomen light brownish-grey to reddish-brown. Forewing slightly expanding distally; costa bent outwards in basal third, then straight or slightly arced outwards; apex slightly protruding. Ground colour varying from whitish grey to beige, yellowish brown, dark grey, fuscous brown or reddish brown; markings obsolescent or forewing with conspicuous costal blotch. A very variable species (see 'variation'). Hindwing grey, paler basally.

male genitalia A. comariana
Genitalia: Tegumen slender, tapering apically; socii long, broader anteriorly than posteriorly, rounded apically; tuba analis delicate, slender, provided with very small median projection ventrally. Valva slender, elongate with long, well sclerotized costa; sacculus long, with long, delicately spined and hairy, posterior portion; ventral margin of sacculus concave before middle, posterior edge of this concavity nearly straight; brachiola rather small, elongate. Aedeagus very short, slightly tapering terminally; cornuti absent, or in the shape of fine spines.

Female:

External characters: Similar to male.

female gen. A. comariana
Genitalia: Papillae analis with rather short posterior portions; apophyses posteriores relatively long; sterigma rather delicate, anterior corners elongated, somewhat curved, pointed apically; ostium bursae large; ductus bursae transparent, slightly broadening posteriorly; corpus bursae small; signum vestigial, sculptures delicate.

Variation:

The ground colour and markings vary considerably in Acleris comariana.
Several 'forms' are recognized. In the obscurely marked form, the ground colour varies from dark grey to fuscous brown, with weak yellowish brown strigulation. The markings are obsolescent or partially indicated by a slightly darker shade of ground colour and small tufts of raised blackish scales. Other forms can be divided into two groups according to the colour of the costal blotch. In one group the blotch varies from fuscous to deep blue-black. The ground colour may be light beige, weakly strigulated with a darker shade; in this form the sub-basal fascia is vestigial. It may also be yellowish brown with weak strigulation. Or also whitish grey coarsely irrorate with fuscous, with a reddish brown suffusion from costal blotch to dorsum.
In the other group, the costal blotch varies from light brown to reddish brown. The ground colour may be light grey with weak strigulation. It may also be whitish grey with variable fuscous irroration and a reddish brown suffusion from costal blotch to dorsum. Finally, the ground colour may be reddish brown; in this form the sub-basal fascia is obsolescent (Bradley et al., 1973).

Biology:

rolled strawberry leaf
rolled apple leaf (comariana)
Acleris comariana is a biovoltine species. It overwinters as egg laid singly on mature leaves, mainly on the undersides. Descriptions of petioles and stipules as oviposition sites do not hold true for present-day strawberry cultivars. In the UK, eggs hatch in April or early May. At first, larvae attack the young, unfurling leaves; later, they feed in spun leaves, which may sometimes be webbed to blossom trusses or small fruitlets. Larvae also feed directly in the flowers, sheltering beneath lightly webbed-down petals. By early to mid June, first generation larvae are full-grown, having passed through six instars. They pupate in a silken cocoon in a folded leaf or between spun leaves. Adults appear from mid June to July; they also lay eggs singly on the foliage. These eggs hatch in 10-14 days and a second generation of larvae then feeds from late July to September. Adults of this generation fly from September till October or early November (after Alford, 1984).
Specimens from Korea, studied by Byun et al., 1998, were collected in June and in October.

Host plants:

Acleris comariana is a pest of cultivated and wild strawberry (Fragaria), but it is also known from fruit trees (Malus, Pyrus), Potentilla palustris and Geum rivale. It also occurs on ornamental plants e.g. Azalea (Rhododendron).

Damage:

damaged leaf of pear tree
Most larvae feed on the leaves of the host plant. On strawberry, heavy infestations can lead to severe defoliation, especially when members of the second generation are present on the new summer growth. Damage to flowers and young fruitlets will result in the loss or malformation of fruits but compared with other strawberry-feeding tortricids the proportion of larvae attacking blossoms and fruitlets is usually small (Alford, 1984).
The importance of this pest is often overrated and in many areas populations are kept under control by natural enemies.

Distribution:

Palaearctic region, from North Ireland to South Korea and Japan; North America

Pheromone:

Pheromone unknown.

Parasitoids:

Lithomastix arestix (Walker) (Chalcididae)
Mesochorus brevicollis Thomson (Ichneumonidae)
Phaeogenes fulvitarsis Wesmael (Ichneumonidae)
Itoplectis altemans Gravenhorst (Ichneumonidae)
Chorinaeus sp. (Ichneumonidae)
Phytodietus sp. (Ichneumonidae)
Horogenes sp. (Ichneumonidae)
Campoplex sp. (Ichneumonidae)
Gelis sp. (Ichneumonidae)
Glypta monoceros Gravenhorst
Microbracon acallae Bengst. (Braconidae)
Microgaster laeviscula Thomson (Braconidae)
Ascogaster sp. (Braconidae)
Eubadizon sp. (Braconidae)
Meteorus sp. (Braconidae)
Elodia tragica Meigen (Tachinidae)

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