Aleiodes abraxanae, van Achterberg, Cornelis & Shaw, Mark R., 2016

van Achterberg, Cornelis & Shaw, Mark R., 2016, Revision of the western Palaearctic species of Aleiodes Wesmael (Hymenoptera, Braconidae, Rogadinae). Part 1: Introduction, key to species groups, outlying distinctive species, and revisionary notes on some further species, ZooKeys 639, pp. 1-164 : 30-34

Aleiodes abraxanae sp. n. Figs 7-8, 9-19

Aleiodes abraxanae van Achterberg in Lozan et al. 2010: 19. Nomen nudum.

Rogas circumscriptus auct. p.p. (not Nees 1834).

Aleiodes armatus auct. p.p. (not Wesmael 1838).

Type material.

Holotype, ♀ (NMS, Edinburgh), "[England], Otmoor N. R., Oxon., H[ost]: Abraxas grossulariata [on] Prunus spinosa , HLC [= host larva collected] 13.v.[19]79, PLE [parasitoid larva evident = mummification in the case of Aleiodes ] 11.vi.[19]79, PIE [= parasitoid imago emerged] 4.vii.[19]79, M.R. Shaw". Paratypes (74 ♀, 34 ♂): 52 ♀, 25 ♂ reared from larvae of the geometrid Abraxas grossulariata (Linnaeus) collected in v/vi, em (v)vi/vii as follows: 14 ♀, 4 ♂ (NMS, RMNH) England, Oxford, Otmoor, 1972, 1973, 1979, M.R. Shaw; 2 ♀, 3 ♂ (NMS, BMNH) England, West Sussex, Littlehampton, 1978, 1979, A.A. Allen; 1 ♂ (NMS) England, West Sussex, Hove, 1982, A.R. Cronin; 3 ♀, 1 ♂ (NMS, AAC) England, Surrey, Salfords, 1976, A.A. Allen; 1 ♀, 1 ♂ (NMS, RMNH) England, Berks, Maidenhead Thicket, 1979, M.R. Britton; 4 ♀, 4 ♂ (NMS, RMNH) England, Bucks, Butlers Hangings, 1979, M.R. Shaw; 2 ♀ (NMS) England, Bucks, Milton Keynes, 1984, J.P. Brock; 1 ♀ (BMNH) England, Cambridge, 1913, L. Doncaster; 2 ♀ (NMS) England, Westmorland, Beetham, 1991, M.R. Shaw; 11 ♀, 1 ♂ (NMS, BMNH) Scotland, Fife, St Andrews, 1935, 1936, 1938, D.J. Jackson; 1 ♀ (NMS) Scotland, Stirling, D.J. Jackson; 8 ♀, 7 ♂ (NMS, RMNH) Scotland, Orkney, Mainland, Waulkmill Bay, 2009, K.P. Bland; 1 ♂ (NMS) Scotland, Orkney, Mainland, Caldale Bottom, 2009, K.P. Bland; 2 ♀ (NMS) Scotland, Orkney, Mainland, Redland, 2009, K.P. Bland; 1 ♂ (NMS) Scotland, Orkney, Hoy, Nowt Bield, 2009, K.P. Bland; 1 ♂ (NMS) Scotland, Orkney, Hoy, Enegars, 2004, S. Gauld; 2 ♀ (SDEI) Germany, Sachsen-Anhalt, Wolfen, 1957, B. Stehlik; additionally 1 ♀ (NMS) from the Otmoor locality, host larva collected 8.x.1978, mummified 4.vi.1979, emerged 3.vii.1979, M.R. Shaw. Non-reared specimens: 1 ♂ (NMS) England, Cambridge, Chippenham Fen, 9.vii.1983, M.R. Shaw; 1 ♀ (NMS) England, Hunts, Monks Wood, 31.viii.2005, G.R. Broad; 1 ♂ (NMS) England, East Gloucester, Eastleach, 8.viii.2006, M.R. Shaw; 1 ♀ (BMNH) East Cornwall, Botusfleming, Marshall collection; 4 ♀ (BMNH) England, Oxford, Stanton St. John, 19.viii. 1968 (1) and 4.ix.1968 (3), J.P. Brock; 1 ♂ (BMNH) England, Herts, Whetstone, 24.vii.1961, P.H. Ward; 1 ♀, 1 ♂ (BMNH) England, Northampton, Spratton, x.1975 and vii.1976 respectively, I. & P. Gauld; 2 ♀ (BMNH) British Isles, Harwood coll.; 1 ♀ (BMNH) presumed British, A. Matthews in Lyle coll.; 3 ♀ (BMNH) presumed British, Stephens coll.; 1 ♀ (CMIM) England, Dorset, Weymouth 24.vi.1899, Peachell; 1 ♀ (CMIM) England, West Suffolk, Old Newton; 1 ♂ (CMIM) England, East Suffolk, Monk’s Soham, 18.vii.1933; 2 ♀, 1 ♂ (AAC) Eng land, South Devon, Shaldon, 7.viii.1978 (1 ♀) and 6.viii.1979 (1 ♀, 1 ♂), A.A. Allen; 2 ♀ (NMS, RMNH) Wales, Anglesey, Llangristiolus, 27. viii– 25.ix.1982, S.A. & D.C. Wilkinson; 1 ♀ (NMS) Scotland, West Ross, Sheildaig, viii. 1991, I. MacGowan; 2 ♂ (NMS) Scotland, South Uist, Loch Eynort, vi.1988, D. Whiteley; 2 ♀ (ALC, RMNH) Czech Republic, South Bohemia, Šumava Boubinský Pralés, virgin forest, 1000-1300 m, light trap, 22-24.vii.2003, I. Jaroš & K. Spitzer; 1 ♀ (ALC), Czech Republic, South Bohemia, Šumava Mts, 740 m, peat bogs near Mrtvý, light trap, 21-24.viii.2001, I. Jaroš & K. Spitzer; 1 ♂ (NMS) Finland, Satakunta, Pori, 1991, K. Ruohomäki; 1 ♀ (NMS) Sweden, Gotland, Sundre, Barrshage, vii/viii.2004, N. Ryrholm.

Molecular data.

MRS391 (Sweden JF962827, CO1), MRS636 (Scotland HQ551278/HQ551264, CO1), MRS637 (Scotland HQ551262, CO1 + KU682263, 28S), MRS694 (Scotland HQ551277, CO1).

Biology.

Univoltine and presumed monophagous parasitoid of Abraxas grossulariata , overwintering in the living host larva and killing it in early summer in its penultimate instar. Mummy (Fig. 8) black and moderately swollen. In Britain very widespread and present in most well-established colonies of the host, on its various foodplants (rearing records from Prunus spinosa , Ribes uva-crispa , Ribes nigrum , Calluna vulgaris and Euonymus japonicus ). It has not been reared from collections of the congeneric Abraxas sylvata (Scopoli) which hibernates as a pupa and would not provide a means for the parasitoid to overwinter. The essentially univoltine host overwinters as a small caterpillar, within which the parasitoid overwinters as an early (probably first) instar larva. The mummies of penultimate instar hosts are made in exposed situations on very narrow stems etc. in about early June and, no doubt aided by their almost black and hence heat-absorbing colour, adult emergence follows quickly; the mummies otherwise being subject to high levels of pseudohyperparasitism. The adult females are unwilling to mate soon after their emergence in the morning but become highly receptive in early evening, offering themselves to males at the first contact which sometimes happens before the males are fully aware of them, and repeated copulation bouts with the same or another male frequently ensue over the next tens of minutes. The new generation of hosts is not available for several weeks, but the adult females are long-lived (confirmed in captivity), and have been collected from June well into the autumn (as late as October). The host has been in severe decline in Britain in recent years, apart from its strong presence on Calluna in parts of Scotland, which remain also a stronghold for the otherwise declining parasitoid. When surveying for the presence of the parasitoid, undersized hosts collected in mid to late May are the most likely to yield results.

Diagnosis.

Pterostigma of both sexes blackish or dark brown medially, border between dark and pale part sharp, contrasting with each other (Figs 7, 9); temples directly strongly narrowed (Fig. 18) and comparatively wide in lateral view (Fig. 17); OOL about equal to diameter of ocellus; propodeum and first tergite yellowish or medially brown (Fig. 11); vein 2-SR of fore wing yellowish as vein 1-R1 (Fig. 9); head moderately transverse (Fig. 18); antennal segments of ♀ 41-45, of ♂ 40-44; subapical antennal segments slender (Fig. 15); vertex may be distinctly rug(ul)ose and meso pleuron only coriaceous medially (Fig. 10); body entirely brownish yellow, at most propodeum and first tergite medially brown. Similar to Aleiodes hellenicus Papp, 1985, but Aleiodes hellenicus has pterostigma of both sexes completely pale yellowish and precoxal area usually with rugae medially.

Description.

Holotype, ♀, length of fore wing 5.1 mm, of body 6.2 mm.

Head. Antennal segments of ♀ 43, length of antenna 1.3 × fore wing, its subapical segments about 2.3 × as long as wide; frons only coriaceous, matt; OOL 0.9 × diameter of posterior ocellus and coriaceous; vertex coriaceous, matt; clypeus convex, coriaceous; ventral margin of clypeus thick and depressed (Fig. 16); width of hypoclypeal depression 0.4 × minimum width of face (Fig. 16) and face coriaceous; length of eye 3.8 × temple in dorsal view and temple directly narrowed behind eye; occiput behind stemmaticum coriaceous and occipital carina interrupted by somewhat less than width of ocellus (Fig. 18); clypeus partly above lower level of eyes (Fig. 16); length of malar space 0.3 × height of eye in lateral view; eyes distinctly protruding (Figs 16, 18).

Mesosoma. Mesoscutal lobes largely coriaceous, matt, but medio-posteriorly longitudinally rugose; notauli narrow and smooth, posteriorly lost in rugose area; prepectal carina medium-sized, reaching anterior border; precoxal area of mesopleuron and metapleuron coriaceous, matt; mesopleuron above precoxal area (except smooth and shiny speculum) coriaceous, but dorsally rugose; mesosternal sulcus narrow and shallow, impressed and without carina posteriorly; mesosternum angulate posteriorly; scutellum slightly convex, coriaceous, and carinate laterally; propodeum evenly convex and rugose but anteriorly weakly so, median carina complete, without tubercles.

Wings. Fore wing: r 0.4 × 3-SR (Fig. 9); 1-CU1 horizontal, 0.35 × as long as 2-CU1; r-m 0.7 × 2-SR, and 0.5 × 3-SR; second submarginal cell medium-sized (Figs 7, 9); cu-a vertical, not parallel with CU1b, straight (Fig. 9); 1-M slightly curved posteriorly. Hind wing: apical half of marginal cell parallel-sided; 2-SC+R short and longitudinal; m-cu present but unpigmented.

Legs. Tarsal claws setose; hind coxa coriaceous, largely matt; hind trochantellus 2.6 × longer than wide; length of fore and hind femora 6.1 and 4.9 × their width, respectively (Figs 12-13); inner apex of hind tibia without comb; length of inner hind spur 0.25 × hind basitarsus.

Metasoma. First tergite nearly as long as wide posteriorly, moderately convex and latero-posteriorly lamelliform; first and second tergites densely and finely longitudinally rugose, robust (Fig. 11), with distinct median carina; medio-basal area of second tergite obsolescent; second suture shallow and crenulate; basal half of third tergite finely rugose, remainder of metasoma largely superficially coriaceous; fourth and apical third of third tergite without sharp lateral crease; ovipositor sheath densely setose.

Colour. Brownish yellow; apical fifth of antenna and dorsally propodeum dark brown; ovipositor sheath black; palpi, tegulae, apical 0.4 of first tergite and more or less second tergite pale yellowish; veins (but distally from 2-SR yellowish) and pterostigma (except yellow base and apex) dark brown; border between dark and pale part of pterostigma sharp, contrasting with each other (Figs 7, 9); wing membrane subhyaline.

Variation. Length of fore wing 4.4-5.3 mm; antennal segments of ♀ 41(10), 42(18), 43(30), 44(6), and 45(1), of ♂ 40(3), 41(7), 42(8), 43(4), 44(4); stemmaticum of male black and of female brownish yellow; basal 0.2-0.5 of pterostigma pale yellow, rarely largely yellow and only medially darkened; first tergite yellowish or infuscate medially.

Etymology.

Named after the generic name of its host: Abraxas Leach.

Distribution.

*British Isles (England, Scotland, Wales), *Czech Republic, *Finland, *Germany, *Sweden.

Note.

The males of this species have on average about one antennal segment less than females.