Aleiodes angustipterus, 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 : 36-40

Aleiodes angustipterus sp. n. Figs 35, 36-47

Type material.

Holotype, ♀ (RMNH, Leiden), "Nederland (Dr.), Wijster, opposite Biol. Station, 12-19.viii.1977, C. v. Achterberg". Paratypes (15 ♀): 1 ♀ (NMS), England, Cumbria, Whitbarrow, Howe, MV light, 24.viii.1995, M.R. Shaw; 1 ♀ (NMS), England, Norfolk, Scarning, TF981120, 6. vii– 1.ix.1988, A.P. Foster/NCC; 1 ♀ (NMS), England, Norfolk, Sutton, TQ373235, water trap, 21. viii– 4.ix.1986, A.P. Foster/NCC; 2 ♀ (NMS), Wales, Anglesey, Fedw Fawr, SH6081, MV light, 11.viii.2003, M.R. Shaw; 1 ♀ (NMS), Wales, Gwent, Magor Marsh, ST425865, water trap 8-21.vii.1988, P. Holmes/NCC; 1 ♀ (Tullie House Museum, Carlisle), Scotland, Dumfriesshire, Gretna, Springfield, 17.viii.1939, J. Murray; 1 ♀ (BMNH), Jersey, Trinity, Howard Davis Farm, Rothamsted trap 18. iv– 3.xii.2004, A. Vautier/P. Gould; 1 ♀ (FMNH), Finland, U. Vantaa. 6690:384. ex larva Hypenodes humidalis 27.v.1974, cocoon [in which the mummy formed?] 19.vi.1974, em. 3.vii.1974, E.O. Peltonen; 1 ♀ (BZL), Greece, Thráki NW, Mt. Menikio, 12.viii.2010, J. Halada; 1 ♀ (NMS), Lithuania, Cerkelia peat bog, 3.ix.2006, A. Lozan; 1 ♀ (M. Riedel Collection), Russia, E. Siberia, 10 km E Irkutsk, 8.viii.2005, Berlov; 1 ♀ (NMS), Portugal, Azores, ca 2008 [per D.L.J. Quicke, no further data]; 1 ♀ (MRS), China, Yangtze River near Fengdu, 15.vii.2002, M.R. Shaw; 1 ♀ (RMNH), Japan, Kusakai, Kawai V., Iwate, 3-4.viii.1981, A. Takasu.

Molecular data.

MRS172 (China KU682231, CO1), MRS279 (Wales KU682232, CO1), MRS280 (Wales KU682233, CO1), MRS822 (Azores KU682246, CO1).

Biology.

No males have been seen, suggesting that this species might be thelytokous. Only a single reared specimen examined, from Hypenodes humidalis Doubleday ( Erebidae : Hypenodinae ). From the specimen labelling, the mummy appears to be formed in the host cocoon (but this has not been examined) and the adult emerged the same year. From this, and the flight data (vii-viii), it is surmised that it is a univoltine species, overwintering in the partly fed host larva. Hypenodes humidalis occurs in both acidic and alkali marshy areas, and the larva feeds on plant debris certainly including dead or dying Molinia caerulea (G.M. Haggett, personal communication). Indeed, when known the collecting sites of Aleiodes angustipterus have mostly been wet grasslands, including fens and bogs, but at least one specimen was collected in woodland on a limestone hill (Whitbarrow) which may suggest a wider host range.

Diagnosis.

Head subglobular (Fig. 46) and body slender; antenna of ♀ without a pale submedial band; antennal segments of ♀ 36-40; eye rather small (Fig. 45); OOL 1.2 × posteior ocellus; speculum of mesopleuron rugose or reticulate and dull as is remainder of mesopleuron (Fig. 38); propodeum slightly elongate (Fig. 38); fore wing narrow (Fig. 36); pterostigma brown; hind coxa distinctly shorter than first tergite; hind femur 6-7 × as long as its maximum width; hind trochantellus slender (Fig. 40); dorsal carinae of first metasomal tergite lamelliform protruding basally; second tergite with small smooth triangular area medio-basally and tergite rather short (Fig. 39); third tergite weakly sculptured; fourth tergite partly or entirely without sharp lateral crease, fourth and following tergites partly retracted and largely smooth. Morphologically similar to Aleiodes jakowlewi from Finland, Sweden and N. Russia, but Aleiodes jakowlewi has the hind coxa about as long as first tergite and second tergite comparatively long (hind coxa distinctly shorter than first tergite in Aleiodes angustipterus (Fig. 35) and second tergite comparatively short (Figs 35, 39)); fourth tergite with distinct sharp lateral crease and basally rugulose (fourth tergite partly without distinct sharp lateral crease, partly retracted and largely smooth); third tergite strongly sculptured (third tergite weakly sculptured); pterostigma dark brown with basal third pale (pterostigma dark brown); eye comparatively large (eye comparatively small); antenna of ♀ sometimes with a narrow white or pale yellowish submedial band (antenna of ♀ without a pale submedial band); antennal segments of female 49-52 (36-40).

Description.

Holotype, ♀, length of fore wing 3.2 mm, of body 4.1 mm.

Head. Antennal segments of ♀ 36, length of antenna 1.1 × fore wing, its subapical segments about 1.4 × as long as wide; frons granulate, rather shiny; OOL and POL 1.2 and 1.5 × width of posterior ocellus, respectively; vertex superficially granulate-coriaceous, rather shiny; clypeus convex and coriaceous; ventral margin of clypeus thick and depressed (Fig. 44); width of hypoclypeal depression 0.4 × minimum width of face (Fig. 44) and face coriaceous with some rugulae; length of eye 2.4 × temple in dorsal view and temple directly narrowed behind eye; head subglobular (Fig. 46); occiput behind stemmaticum coriaceous with satin sheen; occipital carina complete and dorsally arched (Fig. 46); clypeus partly above lower level of eyes (Fig. 44); length of malar space 0.4 × height of eye in lateral view; eyes somewhat protruding (Figs 44, 46).

Mesosoma. Mesoscutal lobes coriaceous-rugulose, matt, but medio-posteriorly longitudinally rugose and anteriorly low; notauli narrow and crenulate, but sculpture largely lost; prepectal carina medium-sized, reaching anterior border; precoxal area of mesopleuron, area below it and mesosternum largely reticulate-rugose; remainder of mesopleuron (including speculum) rugose or rugulose and matt (Fig. 38); metapleuron rugose, matt; mesosternal sulcus deep and sparsely crenulate; mesosternum rounded posteriorly; scutellum slightly convex, rugulose, and laterally with irregular carina; propodeum flattened, without tubercles and coarsely rugose, median carina incomplete, posterior 0.3 absent.

Wings. Fore wing: r 0.4 × 3-SR (Fig. 36); 1-CU1 horizontal, 0.5 × as long as 2-CU1; r-m 0.8 × 2-SR, and 0.5 × 3-SR; second submarginal cell medium-sized (Fig. 36); cu-a vertical, not parallel with CU1b, straight; 1-M straight and 1-SR angled with 1-M. Hind wing: apical half of marginal cell slightly widened; 2-SC+R short; m-cu obsolescent.

Legs. Tarsal claws with yellow bristles; hind coxa rugulose and with spaced oblique rugae, with satin sheen and 0.7 × as long as first tergite; hind trochantellus 2.4 × longer ventrally than wide; length of fore and hind femora 5.8 and 6.1 × their width, respectively (Figs 40-41); inner apex of hind tibia without distinct comb; length of inner hind spur 0.25 × hind basitarsus.

Metasoma. First tergite 1.1 × as long as wide posteriorly, convex anteriorly and dorsal carinae lamelliform protruding basally; first and second tergites longitudinally rugose, robust (Fig. 39), with distinct median carina; medio-basal area of second tergite minute; second suture narrow and crenulate; basal half of third tergite largely superficially coriaceous, with some fine longitudinal elements; third tergite with complete sharp lateral crease, absent on following tergites; ovipositor sheath densely setose and apically acute.

Colour. Dark brown; head (except stemmaticum), mesoscutum and scutellum medially, tegulum, legs (but femora largely infuscate), patch on posterior third of first tergite, large triangular patch on second tergite (Fig. 39) and anterior patch of third tergite brownish yellow; fourth–seventh tergites yellow; mouthparts, humeral plate and metasoma ventrally pale yellow; ovipositor sheath black; veins and pterostigma dark brown; wing membrane infuscate.

Variation. Antennal segments of ♀: 36(2), 37(4), 38(2), 39(3), 40(2). The male is unknown. Pale patches of first and third tergites sometimes absent; hind femur 6.1-7.0 × as long as wide and hind trochantellus 2.4-3.0 × longer ventrally than wide. Central antennal segments vary from 1.2-1.5 × as long as wide, but in one specimen about 2.2 times - although its metasoma (at least posteriorly) is female, it seems possible that this individual is an intersex.

Etymology.

From “angustus” (Latin for “narrow”) and “pteron” (Greek for “wing”), because of the narrow wings.

Distribution.

*British Isles (England, Scotland, Wales, Jersey), *Finland, *Greece, *Lithuania, *Netherlands, *Portugal (Azores), *Russia (Siberia), *China (Chongqing), *Japan (Honshu).

Note.

CO1 sequences obtained from the paratypes from Azores and China group closely with those from Britain, and this seldom-collected species appears to have a very wide distribution.