Author: Filipjev, 1930
larva: Spruce web worm
Species Overview:
Adult: wingspan 30-40 mm, females larger than males; forewings brownish black with pale yellow markings (asymmetrical in right and left wings) consisting of a series of oblique irregular transverse streaks on costa, some longitudinal rows of rounded dots, elongate-ovate spots between veins Cu1-M2, mixed with orange in basal three-quarters of the wing and a bright orange spot at termen. Hindwings dark brownish-black with ochreous orange markings.
Larva: ca. 28 mm long; body pale green; pinacula pale brown, moderately small; head brownish yellow, pattern distinct, brown or dark brown; region of stemmata with dark pigments; thoracic shield brownish yellow; anal shield concolorous with body; anal fork well developed. Seta SD2 separated from the SD1 pinaculum on abdominal segments 1-8 [Eurydoxa advena larva].
Pupa: ca. 28 mm long, robust, slightly flattened dorso-ventrally; no rows of spines present on the dorsum of the abdominal segments; setae whitish [Eurydoxa advena pupa].
Taxonomic Description:
Male:
Eurydoxa advena male
External characters: 30-35 mm wingspan. Head pale yellow, mixed with dark brown, except for a narrow black edge along eyes; antenna dark blackish brown, ciliate; collar black, edged with pale yellow, tegula bordered with the same colour; metathorax mixed with sparse, pale yellow scales and provided with three minute dots; abdomen blackish brown, pale yellow ventrally, segments edged with the same colour posteriorly, anal segment blackish. Forewing brownish black with pale yellow markings (asymmetrical in right and left wings); a series of oblique irregular transverse streaks on costa, some of which furcate, others interrupted or divided into two or three small rounded dots; some longitudinal rows of rounded dots; somewhat curved elongate-ovate spots between veins Cu1-M2 mixed with orange in basal three-quarters of the wing, followed by an ovate bright orange spot at termen; two small rounded pale yellow dots along termen above the orange spot. Cilia greyish black with a pale yellow dot at apex. Hindwing dark brownish-black, appearing darker where the spotted black markings of the underside show through. Markings ochreous orange; a narrow streak with somewhat diffused margins along lower edge of discal cell from base to two-thirds of wing, dilated along apical third with two dents above and few diffused dots above those; a more or less distinctly interrupted narrow streak between vein 1A and CuA 2; a suffused and interrupted narrow subterminal streak; and sometimes the orange makings are very weak and almost obsolete; costa whitish. Cilia pale yellow, blackish in basal third.
male gen. Eurydoxa advena
Genitalia: Tegumen short, broad; uncus short, rounded apically; gnathos arms dilated at base, terminal part curved; socii broad, almost reaching the hook of gnathos. Valva not tapering distally, with long, dense bristles terminally; sacculus well terminating in a short dent; transtilla band-shaped. Aedeagus slender; very long, curved, well sclerotized dorsally in distal part, with a subapical dent situated laterally.
Female:
Eurydoxa advena female
External characters: 35-40 mm wingspan. Head black, vertex between antennae and face yellow, except for a narrow black edge along eyes; antenna black; collar black edged with pale yellow; thorax black, patagium broadly edged with pale yellow; abdomen blackish brown, posterior parts of the segments yellowish. Forewing black with yellow markings, consisting of oblique irregular transverse bands and dots; an ovate bright orange spot at termen. Cilia black. Hindwing black, markings orange; a narrow streak with somewhat diffused edges along lower border of discal cell from base to two-thirds of the wing length, dilated along the apical third with two dents above; a series of five rounded dots at costa, another series of three rounded dots sub-terminally, and a series of five or six rounded dots anally; a narrow streak of pale orange colour along anal fold from base of wing to dorsum. Cilia pale orange; basal half blackish (Diakonoff, 1950a; Diakonoff, 1970; Yasuda, 1975b).
female gen. Eurydoxa advena
Genitalia: Sterigma with a rounded dilation medially. Ventral arms of anterior apophyses form a sclerotized transverse band above the ostium (and not, as usually is the case in Tortricinae, below the ostium). Ostium strong, funnel-shaped, sclerotized and fused with seventh sternum. Ductus bursae long, narrow; signum a somewhat concave, serrate plate.
Biology:
There is a single generation yearly. The moth is on the wing from late July to mid August. The larvae of some early instars feed in the young needles for a short time and then they find suitable places among the needles to spin protective coverings in which they hibernate. The larvae become active in the spring. Later, they feed tying the tips of several twigs together to form a nest. The full-grown larvae spin loose cocoons either in the nest or on twigs and pupate in them (Yasuda, 1975b).
Host plants:
Abies veitchii, Abies sachalinensis and Picea jezoensis.
Damage:
Larvae feed on the needles of Abies and Picea.
Distribution:
Japan: Hokkaido, Honshu; Russia: Ussurijskij Krai, S. Sakhalin, S. Kuril Isl., Primorsk.
Pheromone:
Pheromone unknown.
Parasitoids:
Phaeogenes spiniger (Gravenhorst) (Ichneumonidae)
Phaeogenes eurydoxae Uchida (Ichneumonidae)
Omorgus shikotensis Uchida (Ichneumonidae)
Meterorus sp. (Braconidae)
Myxexoristops blondeli Robineau-Desvoidy (Tachinidae)
Zenilali (Serixozenillia) albipila Mesnil (Tachinidae)
Nemorilla floralis Fallén (Tachinidae)