Eutanyacra CAMERON

A. M, 2011, Illustrated key to the genera of the subtribe Amblytelina of Palaearctic (Hymenoptera, Ichneumonidae, Ichneumoninae, Ichneumonini), Linzer biologische Beiträge 43 (1), pp. 597-711 : 666-668

11. Eutanyacra CAMERON

Eutanyacra CAMERON 1903 - Trans. Ent. Soc. London: 227.

Type species: Eutanyacra pallidicoxis CAMERON.

Eutanyacra: HEINRICH 1961 - Syn. Nearct. Ichn. Stenop. 23: 422-423.

Eutanyacra: HEINRICH 1977 - Ichn. Florida and Neigb. States 9: 103-104.

Eutanyacra: RASNITSYN 1981 - Opr. Faun. SSSR 3 (3): 568, 622.

D i s t r i b u t i o n: Holarctic and Oriental Regions, Australia (1 species). Most species in Nearctic.

I n t r o d u c t i o n:

Bristle-shaped, strongly attenuated to apex flagellum, in males with long tyloides from the first segments, mandibles with two teeth with often truncated upper tooth in females and more or less sharpened in males, more or less shortened propodeum with almost square or transverse area superomedia are characteristic to representatives of Eutanyacra . Apex of females abdomen is as a rule, slightly compressed from sides. Hypopygium of females is with bunch or fringe of long, stiff bristles on the middle of the apical part, and in males with long and sharpened median process.

The analogous bunch of bristles is characteristic also to females of Triptognathus BERTHOUMIEU , males of which also with long sharpened median process of hypopygium. Presence of bunch of stiff bristles on apex of hypopygium and more often truncated upper tooth of females’ mandibles and presence of long median process of males hypopygium make it possible to distinguish the representatives of Eutanyacra from Diphyus KRIECHBAUMER. From relative genus Spilichneumon THOMSON females of Eutanyacra are differed beside bunch of bristles on hypopygium by always bristleshaped, long and strongly attenuated to apex flagellum, by shortened propodeum, and males also by more short (transverse) area superomedia.

M o r p h o l o g y:

F l a g e l l u m: Of female always bristle-shaped, stout up to middle and strongly attenuated and sharpened to apex, with usually shortened to moderately elongated and sharply differentiated basal segments. Flagellum of males with closely merged segments and long row of long tyloides from segment 1, 2 or 3.

H e a d: Temples behind eyes from moderately roundly narrowed to moderately swollen. Mandibles normal, uniformly narrowed to the apex with two teeth, with upper tooth longer than lower one, in females usually with blunted and flattened upper tooth; clypeus broad, flat or slightly convex, with straight front margin.

T h o r a x: Mesonotum slightly longer than breadth at middle, from almost flat to slightly convex, with weak notauli at base or without them, its surface punctured, shining between punctures (extremely densely punctured, dull in Eutanyacra rasnytsini HEINRICH); axillary tongue expressed, but weak; scutellum moderately elevated above postscutellum (more appreciably in males) with flat or slightly convex horizontal surface, not carinated. Hind margin of metanotum with projections. Horizontal part of propodeum shorter than declivous one (propodeum shortened); area superomedia usually wider than length, sometimes square; costulae usually absent; coxal carina usually only just marked or indistinct; areae dentiparae at apices with slight denticles or without them; spiracles large, long.

L e g s: Moderately slender to stout. Hind coxae of females without scopa.

W i n g s: Areolet, pentagonal, big; radius almost straight, slightly curved only at apex; nervulus postfurcal or interstitial ( E. glaucatoria F.).

A b d o m e n:Offemalesamblypygous, rather stout, slightly compressed from sides at apex, with often retracted tergite 6; sheath of ovipositor not protrude from above; second tergite usually transverse. Middle field of postpetiolus distinctly expressed and in females longitudinally striated, in males more often irregularly-wrinkled. Gastrocoeli compa- ratively small, narrower than interval between them, more often deep with almost rudimentary or indistinct thyridia; lunulae distinct, of moderate size; tergite 2 usually densely punctured. Sternites 2-3 of females and 2-4 of males with fold; hypopygium of females with bunch of long stiff bristles at apical part, in males with long, sharpened, often broad and compressed from sides median process.

C o l o r a t i o n: Different combinations of red, yellow and black coloration. Females often with wide light bands at apices of front tergites or with apical stripes at apices of apical tergites of abdomen, sometimes interrupted at the middle ( E. glaucatoria F.).

S i z e: Palaearctic species 11-15 mm.

B i o l o g y a n d e c o l o g y:

H o s t s: For 3 species of a genus from the literature the following data about hosts are known: E. crispatoria (L.) – Semiothisa liturata CL. (Geometridae) ; E. glaucatoria (F.) – Catocala nupta L., Mamestra glauca HBN. ( Noctuidae ); E. picta (SCHRANK) – Agrotis exclamationis L., A. segetum DEN. et SCHIFF., A. ypsilon ROTT. ( Noctuidae ) ( HERTING 1976; RASNITSYN 1981).

S p e c i e s c o m p o s i t i o n a n d a b u n d a n c e: Genus Eutanyacra is presented in region of researches by two species – E. crispatoria (L.) and E. glaucatoria (F.). Abundance of this genus in the nature (quantity of the collected individuals / quantity of revealed species of a genus) leads it to the 5th place according to indicator of abundance among Amblytelina and on 28th place among genera of Ichneumoninae St. in the region (27 individuals / 1 species of genus). According to abundance in collections both species are presented approximately in equal quantity.

B i o t o p i c a l d i s t r i b u t i o n: Both species are met in region only in pine forests and in a greatest quantity they are presented in the bog moss pine forests (Pinetum shagnosum). It is necessary to note that in a forest-steppe region of Western Siberia E. crispatoria is presented in mass in birch forests-aspen forests (shelter belts).

S e a s o n a l a c t i v i t y a n d h i b e r n a t i o n: Females of E. crispatoria are active from June till September without distinctly expressed peak. Males are being met from June till October and have distinct peak of activity in August (75 %). Females of E. glaucatoria are active since June till September, also without distinct peak, males are with shorter period of activity from June till August with distinct peak in June (78 %).

Data from the literature about of finding of hibernating females of E. crispatoria (L.), E. glaucatoria (F.) and E. picta (SCHRANK) are adduced in article of A. RASNITSYN (1964).