Aleiodes pictus ( Herrich-Schaeffer , 1838)

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 : 98-102

Aleiodes pictus ( Herrich-Schaeffer, 1838) Figs 272-273, 274-284

Rogas pictus Herrich-Schaeffer, 1838: 156 (type series lost); Shenefelt 1975: 1171 (as synonym of Aleiodes circumscriptus ).

Aleiodes pictus ; Papp 1991: 113 (as synonym of Aleiodes circumscriptus ).

Type material.

Neotype of Aleiodes pictus here designated, ♀ (NMS), "Lower Austria, Raglitz, J. Connell, [ex] Camptogramma bilineata , [coll.] 29.iii.2011, mum. 4.iv.[20]11, em. 29.iv.[20]11, [J. Connell reference number] XI 2.05.05 ♀4, died ca. 10.vii.2011". "Voucher: BFW Sparkling Science Schwarzes C".

Additional material.

*Austria, British Isles (*England V.C.s 3, 15, 16, 20, 22, 23, 28, 29, 30, 31, 40, 59, 65, 69; *Scotland: V.C.s 77, 83, 84, 88, 89, 96, 101, 105, 111; Ireland: “Westport”), *Bulgaria, Czech Republic, *Finland, *France, Germany, Gibraltar (British territory), *Greece, Hungary, *Iceland, *Italy, Netherlands (DR: Drijber, LI: St. Pietersberg, ZH: Den Haag; Meijendel; Goeree; Ouddorp), *Norway, *Poland, *Portugal, *Romania, *Russia, *Serbia, *Slovakia, Spain, Sweden, Turkey. Specimens in NMS, BMNH, OUM, RMNH, ZSSM, SDEI, BZL, ZISP, CMIM, MSC, CNC, UWIM, JLC, H. Schnee collection, H. Haraldseide collection, World Museum Liverpool.

Molecular data.

MRS518 (Austria KU682261, CO1), MRS549 (Austria KU682241, CO1), MRS556 (Austria KU682242, CO1), MRS719 (Austria KU682245, CO1), MRS784 (Austria KU682251, CO1), MRS785 (Austria KU682252, CO1).

Biology.

This is a plurivoltine parasitoid, abundant in grassland habitats, of larvae of both geometrids and noctuids feeding in low vegetation, overwintering as a small larva in that of the host. Mummy made low down, more or less in concealment, brown and not swollen (Fig. 273). Specimens (in NMS unless stated otherwise) reared from wild-collected larvae of the larentiine geometrids Camptogramma bilineata (Linnaeus) (78:2; J. Connell [77 specimens from Austria resulting from a long term survey], A.R. Cronin), Epirrhoe alternata ( Mueller) (1; G.M. Haggett), Lithostege griseata (Denis & Schiffermueller) (3:1; G.M. Haggett), Xanthorhoe fluctuata (Linneaus) (3:2; G.M. Haggett, G.E. King), and from the diverse range of noctuids Hoplodrina ambigua (Denis & Schiffermueller) (2:1; J. Connell/Austria), Hoplodrina sp. ( blanda (Denis & Schiffermüller), octogenaria (Goeze) and superstes (Ochsenheimer) co-occurring but indistinguishable when small) (17:1; J. Connell/Austria), Agrotis exclamationis (Linnaeus) (1; M.R. Shaw/France); Noctua fimbriata (Schreber) (1; J. Connell/Austria); Xestia xanthographa (Denis & Schiffermueller) (1; J. Connell/Austria), Phlogophora meticulosa (Linnaeus) (1; M.R. Shaw); Syngrapha interrogationis (Linnaeus) (1 ZMUO; J. Itämes /Finland). The Austrian material reared by J. Connell resulted from a prolonged survey of grassland caterpillars at a single site. Experimental cultures (specimens in NMS) as follows: Epirrhoe alternata 6:27\1\\1+0, Xanthorhoe fluctuata 2:45\40\\25+14 [other females even more willing to oviposit (6: 86\84) but cultures lost to disease], Xanthorhoe montanata (Denis & Schiffermueller) 3:15\15\\8+2, Xestia xanthographa 2:2\0\\-, Xestia sexstrigata (Haworth) 2:3\1\\0+1, Noctua fimbriata 1:2\0\\- [This female was then boxed with 10 host larvae for 5 days: 6 hosts pupated; the other 4 died and on dissection were found to contain living parasitoid larvae], Diarsi rubi (Vieweg) 3:37\18\\0+12, Phlogophora meticulosa 2:17\0\\-. The males are aggressive and rather indiscriminate in courtship, seeming as interested in females of Aleiodes nigriceps as their own species, but the Aleiodes nigriceps females always repelled them successfully. Males of Aleiodes pictus are, however, somewhat less interested in females of Aleiodes leptofemur . Mating trials between specimens from Hoplodrina spp. and Camptogramma bilineata (all from the same site in Austria) repeatedly indicated that females from both series were less willing to mate with males from the other than with males reared from the same host as themselves; however, several cooperative matings (that then seemed normal, though of often shorter duration) were obtained and (from very limited trials) no difference was seen in behaviour towards hosts by females of different host origin (but Hoplodrina larvae were not available for experiments). However, the possibility that specimens from Hoplodrina (which differ slightly in their morphology, particularly colour) are at least some way towards representing a genetic isolate cannot be ruled out, as most of the experimental results involved females from Camptogramma bilineata (but also the female from Noctua fimbriata whose behaviour was essentially the same). A host range encompassing both Geometridae and Noctuidae is unusual in the genus Aleiodes , but the species is evidently rather specialised to a narrow range of taxa in each family. The adult flight period is May to September in Britain.

Diagnosis.

Antennal segments of ♀ (35 –)36– 40, of ♂ (36 –)37– 41; pale area of orbita of ♀ rather wide (Figs 281-282); mesopleuron with some rugulae; mesoster num almost always strongly darkened or black and usually sharply defined; width of hypoclypeal depression 0.3-0.4 × minimum width of face (Fig. 280); OOL 1.3 × diameter of posterior ocellus; mesoscutum antero-laterally and pronotum medio-anteriorly very often brownish yellow; length of first tergite of ♀ 1.0-1.1 × its apical width; second tergite often less wide than in Aleiodes nigriceps (Fig. 276); fore and hind tarsi comparatively slender (Figs 277-278); pterostigma yellow anteriorly; middle to distal third of hind femur partly or entirely dark brown; mummy not swollen, usually light brown (Fig. 273).

Description.

Neotype, ♀, length of fore wing 4.6 mm, of body 4.9 mm.

Head. Antennal segments 37 (right) and 38 (left), length of antenna 1.2 × fore wing, its subapical segments about 1.6 × as long as wide; frons granulate and some rugulae, with satin sheen; OOL 1.3 × diameter of posterior ocellus (POL equal to ocellus); vertex superficially granulate, with satin sheen; clypeus distinctly convex and largely nearly smooth; ventral margin of clypeus thick and depressed (Fig. 281); width of hypoclypeal depression 0.3 × minimum width of face (Fig. 280) and face mainly granulate-coriaceous with some rugulae medially; length of eye 2.8 × temple in dorsal view and temple gradually narrowed behind eye (Fig. 282); occiput behind stemmaticum granulate-coriaceous and occipital carina absent medio-dorsally and interruption slightly less than width of stemmaticum (Fig. 282); clypeus partly above lower level of eyes (Fig. 280); length of malar space 0.4 × length of eye in lateral view; eyes moderately protruding (Figs 280-282).

Mesosoma. Mesoscutal lobes finely granulate-coriaceous, with satin sheen, but medio-posteriorly rugose; notauli narrow, moderately impressed and finely crenulate, but posteriorly merging in rugose area; prepectal carina narrow lamelliform and reaching anterior border; precoxal area of mesopleuron coriaceous and with some rugae medially (Fig. 275); mesopleuron above precoxal area (except small nearly smooth and shiny speculum) antero-dorsally distinctly rugose and granulate-coriaceous; medially metapleuron granulate, matt; mesosternal sulcus narrow and rather deep, but posteriorly shallow and with a fine carina; mesosternum rather angulate posteriorly; scutellum nearly flat, superficially coriaceous and only antero-laterally carinate; propodeum rather flat and coriaceous with rugae, median carina nearly complete, without tubercles.

Wings. Fore wing: r 0.3 × 3-SR (Fig. 274); 1-CU1 horizontal, 0.4 × as long as 2-CU1; r-m 0.7 × 2-SR, and 0.4 × 3-SR; second submarginal cell slender (Fig. 274); cu-a slightly oblique, not parallel with CU1b, straight; 1-M slightly curved posteriorly. Hind wing: apical half of marginal cell somewhat widened apically (Fig. 274); 2-SC+R subquadrate; m-cu medium-sized, unpigmented; M+CU:1-M = 50:39; 1r-m 0.6 × as long as 1-M.

Legs. Tarsal claws setose; hind coxa granulate-coriaceous, matt; hind trochantellus 2.5 × longer than wide; length of fore and hind femora 6.1 and 4.9 × their width, respectively (Figs 277-278); hind femur pimply; inner apex of hind tibia without comb; length of inner hind spur 0.3 × hind basitarsus.

Metasoma. First tergite 1.1 × as long as wide posteriorly, convex, but posteriorly flattened; first and second tergites densely longitudinally rugose; second tergite slen derer than is usual in Aleiodes nigriceps (Fig. 276), with distinct median carina, with satin sheen; medio-basal area of second tergite absent; second suture distinctly impressed and crenulate; third tergite largely coriaceous (but anteriorly rugose) and medially 0.7 × as long as second tergite (Fig. 276); remainder of metasoma largely nearly smooth and rather shiny; fourth and apical half of third tergite without sharp lateral crease; ovipositor sheath moderately setose.

Colour. Black or brownish black; antenna brown, but scapus and pedicellus dorsally and laterally and apical half of antenna dark brown; malar space (except near eye), palpi, tegulae, fore and middle coxae, trochanters and trochantelli, first tergite medio-posteriorly, second tergite medially and third tergite narrowly medially pale yellowish (Fig. 276); orbita posteriorly and dorsally widely brownish yellow (Figs 281-282) and remainder of head black; dorso-posteriorly pronotum brown; mesoscutum with notaulic and medio-posterior area brownish yellow; mesosternum narrowly anteriorly behind prepectal carina, ventral half of mesopleuron and posteriorly orange brown; hind femur (except basally and apex) dark brown (Fig. 272); scutellum dark reddish brown medially; veins (except dark brown veins 1-SR, 1-M, r and CU1) brown; pterostigma pale yellowish, but posteriorly somewhat darkened (Figs 272, 274); wing membrane subhyaline.

Variation. Length of fore wing 3.8-4.6 mm; antennal segments of ♀ 34(1), 35(5), 36(27), 37(52), 38(64), 39(38), 40(9) and of ♂ 36(9), 37(22), 38(39), 39(34), 40(18), 41(4); vein r of fore wing 0.4 × vein 3-SR; clypeus 0.3-0.4 × as wide as face; length of first tergite of ♀ 1.0-1.1 × its apical width; pterostigma medially and anteriorly yellow; malar space largely dark brown to largely pale yellow; pronotum medio-anteriorly and scutellum brownish yellow or dark brown; medially metapleuron black or orange brown.

Note.

Males have on average about one more antennal segments than females. In some populations pale specimens (including hind femur and much of face) occur that superficially resemble Aleiodes leptofemur , but can be distinguished by their more robust femora. For further notes see Aleiodes nigriceps .