Author: (Walsingham, 1900)
Species Overview:
Adult: 20-32 mm wingspan (females larger than males); forewings pale brownish-ochreous with brownish markings and strigulation; hindwings brownish fuscous.
Egg: greenish yellow; flattened elliptical. Deposited in an imbricate mass on a fully expanded leaf, presumably on the under-side.
Larva: average length 26 mm; body dark green; prothoracic shield and anal shield yellowish brown, with some dark brown pigment; prothoracic pinacula with some brown pigment; pinacula moderately small, pale, easily observed on dorsum; head and thoracic legs black [Choristoneura adumbratana larva ].
Pupa: ca. 10-19 mm; blackish brown; second abdominal segment without a projection directed cephalad; caudal part of dorsum spinose on abdominal segments 1-7 [details pupa C. adumbratana ].
Taxonomic Description:
Male:
Choristoneura adumbratana male
External characters: Wingspan 20-25 mm. Labial palpus and head brownish ochreous, antenna brownish fuscous; thorax darker than antenna. Forewing not expanding posteriorly; costa strongly curved outwards to middle, weakly concave before apex; apex short, somewhat prominent; termen convex and oblique. Costal fold long, slender. Ground colour pale brownish ochreous often with slight olive hue and weak strigulation; markings brownish with same shine. Basal blotch almost completely atrophied; median fascia from beyond one-third of costa to beyond middle of dorsum, with rather straight inner margin, narrower costally than at dorsum; subapical blotch small, darker anteriorly. Cilia light ochreous, grey at tornus. Hindwing brownish fuscous, somewhat suffused ochreous or cream at apex; cilia cream, greyer in anal portion, often mixed with ochreous at apex (after Yasuda, 1975b).
male genitalia C. adumbratana
aedeagus C. adumbratana
Genitalia: Uncus weakly broadening terminally; arm of gnathos fairly long. Valva elongate, somewhat tapering terminally, rounded caudally. Sacculus slender, simple, without ventral processes, with small termination, convex before middle ventrally. Aedeagus with a dent terminally and numerous minute teeth medially.
Female:
C. adumbratana female
External characters: 25-32 mm wingspan forewing not expanding posteriorly, costa strongly curved outwards mainly in basal third, slightly concave subapically; apex short; termen convex. Ground colour as in male but basal area often more strongly suffused with brown and the strigulation more distinct. Median fascia often interrupted at costa. Hindwing brownish fuscous, somewhat suffused ochreous or cream at apex.
female gen. C. adumbratana
Genitalia: Sterigma rather broad; antrum short, curved; ductus bursae very long, broadened posteriorly; cestum very long; signum present.
Taxonomic note:
Dang, 1992, suspects that Choristoneura adumbratana and Choristoneura hebenstreitella are conspecific. Minor differences in the shape of the socius and the degree of spiculation on the aedeagus probably represent intraspecific variation. However, the species are presently recognized as two distinct species.
Biology:
Choristoneura adumbratana is an univoltine species with obligate larval diapause in an early stage. Nothing is known about an initial period of larval activity in the spring, but half-grown larvae are found before apple blooming. They mature 2 or 3 weeks after the petals have fallen. Adults fly in June in Northern Japan.
Host plants:
Apple (Malus pumila, Malus baccata), pear (Pyrus simoni), cherry, Prunus x yedoensis, Salix, Alnus, Quercus acutissima. Soy bean (Glycine) is also rarely attacked.
Damage:
Larvae spin young shoots, and cut petioles of inner leaves. The resultant dead leaves are used to form the larval habitation. This behaviour often kills a terminal shoot as a whole, although the dead part is not dropped off.
Distribution:
Japan (Hokkaido, Honshu); Korea.
Pheromone:
Pheromone unknown.
Attractantia:
Z 11-14Al (Ando et al., 1981)