Spilonota ocellana

Author: (Denis and Schiffermüller, 1775)

Eye-spotted bud moth

Species Overview:

Adult: 12-16 mm wingspan; forewings rectangular, whitish, more or less suffused with grey, marked towards the apex with metallic bluish grey and black, and each with a dark, triangular pre-tornal marking and a blackish, angular basal patch; hindwings dark grey.
Egg: flat and more or less circular; pale yellowish white [Spilonota ocellana egg].
Larva: 9-12 mm long; head varying from reddish brown with a distinct black region of stemmata and postero-lateral bar to reddish brown overlaid with a dark brown or blackish pattern, or shining black; prothoracic plate shining reddish brown or black, medial sulcus pale brown; abdomen dark reddish brown, finely shagreened; pinacula large, shining dark brown; anal plate yellowish brown or brown mottled with darker brown, rounded posteriorly; anal comb present, dark brown; thoracic legs blackish brown or black. The larva of the larch-feeding form is similar but has the general colouration of the abdomen usually pale greyish brown and the pinacula and anal comb almost concolorous with the integument and comparatively indistinct.
A newly hatched larva is pale yellow with a black head and feeds on the underside of the leaf, living in a silken tube open at both ends. Larvae are slow in their movements in comparison to other leaf rollers [Spilonota ocellana larva 1 ].
Pupa: 5.5-8.5 mm long; golden brown, anterior may be darker brown. Cremaster absent, six (rarely seven) caudal spines present that do no extend beyond abdomen; frons without setae; protarsus extending beyond procoxa by 1/3 - 1/2 length of mesocoxa [details pupa S. ocellana ]. In a rolled leaf or in a frass-littered, in a loosely tied cluster of partially eaten dead leaves, or within a bud [S. ocellana pupa in tied leaves ].

Taxonomic Description:

Male:

Spilonota ocellana adult 1
Spilonota ocellana adult 2
Spilonota ocellana adults
External characters: 12-16 mm wingspan. Antenna of male with a small notch immediately beyond scape dorsally. Forewing smooth, without costal fold; termen nearly straight. Ground colour white to ochreous-white, variably suffused with grey, sometimes heavily; markings dark grey; basal and sub-basal fasciae with a plumbeous admixture and strigulated with black, forming a dense and well-defined basal patch, its outer edge angulated above middle; median fascia obsolescent; triangular pre-tornal marking well-developed, usually prominent and heavily marked with black; subterminal fascia hardly determinate, reduced to a suffusion extending from below middle of termen to apex; ocellus elongated transversely and extending into apical area, partially edged with leaden metallic, containing several sometimes confluent black dashes; cilia grey, with a dark basal line. Hindwing dark grey; cilia paler, with a dark sub-basal line (Bradley et al., 1979).

male genitalia S. ocellana
Genitalia: Uncus greatly reduced. Socius erect, short, subtriangular. Gnathos free and weak. Valva elongate, narrow, neck very narrow, cucullus armed with a strong spine. Aedeagus short; supporting arm of anellus very stout; cornuti composed of a cluster elongate spines.

Female:

External characters: Antenna without a small notch immediately beyond scape; otherwise similar to male.

female genitalia S. ocellana
sterigma in S. ocellana
Genitalia: Papilla analis flattened, with numerous hairs; anterior portion narrow and weakly bending inwards. Sterigma fused with seventh abdominal sternite, subtriangular, caudal margin with a median emargination. Ostial opening oval; ductus bursae well-sclerotized, except for a short membranous posterior portion; corpus bursae round, with a pair of short, curved, pointed signa, which are equal in size.

Variation:

Spilonota ocellana adult 3
Spilonota ocellana adult 4
The general colouration of the forewing and the clarity of the markings are variable. The usually clear ground colour in the medial area varies from almost pure white to pale ochreous but not infrequently it is obscured with grey. A rather dark but distinctive form with comparatively narrow forewings, whose larvae feed on larch, has the nearly pure white ground colour coarsely strigulated with blackish grey (Bradley et al., 1979).

Biology:

Spilonota ocellana larva 2
The eyespotted budmoth is univoltine. Eggs are laid singly or in small groups on leaves of the food plant, each female depositing about 50-100. They hatch about a week or two later. The tiny larvae then feed beneath the leaves, each constructing a small tube-like shelter of silk. Individuals feed mainly on leaf tissue but on apple and pear a leaf may be spun to the surface of a fruit, upon which the larva will also graze. It overwinters as a fourth or fifth instar larva within a hibernaculum located in the crotches of small spurs and shoots or in bark crevices. Larvae become active and may bore into young apple buds as early as the green tip stage of 'McIntosh' bud development. They attack blossoms or shoot clusters as development proceeds, often tying the leaves together at their tips. This produces a loose nest, which almost always contains one or more dead or dying leaves that the larva has severed. The presence of dead leaves allows one to distinguish Spilonota ocellana from other species which may form nests during this period. Pupation takes place within a cocoon spun in the larval habitation or amongst dead leaves, adults emerging three to four weeks later. On larch the larva spins several leaves together, which it mines and hollows out. In the autumn it spins a few mined leaves to the upper surface of a twig at a slight angle to its longitudinal axis, there overwintering until the spring when it bores into an expanding bud, feeding and subsequently pupating within.
In the UK, and also in the Netherlands, moths fly in from June to August.
Material from Korea, studied by Byun et al., 1998, was collected in July and August.
In North America (Hudson valley, New York), moths fly from mid June to early September.
(Weires and Riedl, 1991; Bradley et al., 1979; Frankenhuyzen, 1988; Byun et al., 1998)

Host plants:

Polyphagous on a wide variety of trees, shrubs and herbaceous plants, especially Rosaceae, including Malus, Cydonia, Pyrus, Crataegus, Sorbus, Prunus, Rubus and Pyracantha ; also frequently on Salix, Hippophae rhamnoides, Myrica gale, Euphorbia paralias, Carpinus, Alnus glutinosa, Quercus and Rumex obtusifolius. The larva of the larch-feeding form feeds on Larix decidua , Larix leptolepus and probably other species of Larix and is also recorded on Picea sitchensis.

Damage:

Spilonota ocellana damage on larch
ocellana damage (rolled leaf)
ocellana damage (apple fruit)
S. ocellana damage (apple bud)
In the summer, larvae feed between two leaves, or between the leaves and fruit. In the latter case damage to the fruit from the small feeding excavations is sufficient to lower the commercial grade of the fruit. Feeding on the developing fruit by overwintering larvae can be extensive under high population density and may cause fruit to drop or scarred fruit. But attacks in the spring are more significant, infested buds being hollowed out and killed (Weires and Riedl, 1991).
On larch the larva spins several leaves together, which it mines and hollows out. In the autumn it spins a few mined leaves to the upper surface of a twig at a slight angle to its longitudinal axis, there overwintering until the spring when it bores into an expanding bud, feeding and subsequently pupating within (Bradley et al., 1979).

Distribution:

Europe to Eastern Russia and Japan; Madeira; North America.

Pheromone:

Z8-14Ac a : 5 *
Z8-14OH a : 0.07 *
12Ac : 0.03

Components marked with * are involved in attraction (Witzgall et al., 1991b)

Attractantia:

Z 8-14Ac
(Arn et al., 1974)

or

Z 8-14Ac : 99
Z 8-14OH : 1
(McBrien et al., 1991)

or

Z 8-12Ac : 9
E 8-12Ac : 1
(Minks et al., 1977)

Parasitoids:

Europe: Colpoclypeus florus Walker (Eulophidae)
Mesochorus pallipes (Ichneumonidae)
Glypta filicornis (Ichneumonidae)
Itoplectis maculator (Ichneumonidae)
Pristomerus orbitalis (Ichneumonidae)
Diadegma apostata (Ichneumonidae)
Agathis dimidiator (Ichneumonidae)
Braunsia rufipes (Braconidae)
Ascogaster quadridentatus (Braconidae)
Phanerotoma dentata (Braconidae)
Meteorus ictericus (Braconidae)
Apanteles laevigatus (Braconidae)
Apanteles xanthostigma (Braconidae)
Apanteles longicaudis (Braconidae)
Apanteles reicharti (Braconidae)

Canada: Meteorus trachynotus Vier. (Braconidae)
Agathis laticinctus Cresson (Braconidae)
Ascogascer quadridentatus Wesm. (Braconidae)
Scambus hispae Harris (Ichneumonidae)
Atrometus clavipes Davis (Ichneumonidae)
Oedemopsis scabricula (Grav.) (Ichneumonidae)
Trichogramma minutum Ril. (Trichogrammatidae)
Enderus subopacus Gahan (Chalcidoïdea)

USA: Microdus dimidiator Nees (Braconidae)
Microdus rufipes Nees (Braconidae)
Meteorus ictericus Nees (Braconidae)
Meteorus parvulus Thoms. (Braconidae)
Apanteles aristoteliae Vier. (Braconidae)
Ascogaster quadridentatus Wesm. (Braconidae)
Trichogramma minutum Ril. (Trichogrammatidae)
Brachymeria orata Say (Chalcididae)
Pristomerus vulnerator Panz. (Ichneumonidae)
Pimpla nucum Ratz. (Ichneumonidae)



Spilonota albicana (Motschulsky)

In Japan, Spilonota albicana occurs. The species superficially resembles a pale form of Spilonota ocellana [Spilonota albicana adults ], but can be recognized by the reduced basal blotch.
The male genitalia have rectangular socii (tapering in Spilonota ocellana), and the cucullus is slightly broader [socii Spilonota albicana ; valve S. albicana.
The species is recorded from various Rosaceae such as apple, cherry and peach. Also recorded from Crataegus cuneata, Phitinia glabra and Pieris elliptica.s.
Furthermore, it has been recorded as imported on bonsai trees (Malus) from Japan into the Netherlands.

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