Aleiodes grassator (Thunberg, 1822)

van Achterberg, Cornelis, Shaw, Mark R. & Quicke, Donald L. J., 2020, Revision of the western Palaearctic species of Aleiodes Wesmael (Hymenoptera, Braconidae, Rogadinae). Part 2: Revision of the A. apicalis group, ZooKeys 919, pp. 1-259 : 1

Aleiodes grassator (Thunberg, 1822) Figs 365-367 , 368-380 , 381-384

Ichneumon grassator Thunberg, 1822: 256 [examined].

Rogas grassator ; Shenefelt 1975: 1232.

Aleiodes (Neorhogas) grassator ; Papp 1991a: 86.

Aleiodes grassator ; Zaldívar-Riverón et al. 2004: 234; Quicke et al. 2014: 240; Butcher et al. 2014: 458.

Rhogas grassator ab. thoracicus Hellén, 1927: 24; Shenefelt 1975: 1232 (unavailable name).

Rogas (Rogas) flavipalpis Thomson, 1892: 1672 [examined].

Aleiodes flavipalpis ; Papp 1991a: 86 (as synonym of A. grassator ).

Rogas alpinus Thomson, 1892: 1671; Shenefelt 1975: 1217 [examined]. Syn. nov.

Aleiodes alpinus ; Papp 1991a: 90 (as synonym of A. dimidiatus ).

Type material.

Holotype of A. grassator , ♀ (ZMUU), unlabelled. Lectotype of A. flavipalpis , ♀ (ZIL), “åre”, " Sverige, Ǻreskutan I Jemtland/teste Papp, 1983", "Lectotypus Rogas flavipalpis Thomson, 1899 [sic!], Papp, 1983", " Aleiodes grassator Thb., det. Papp J., 1983". Lectotype of A. alpinus, ♀ (ZIL), "[Norway:] Dovre", " alpinus m.", "Lectotypus Rogas alpinus Thoms., 1891, ♀. Papp, 1983", " Aleiodes dimidiatus var. alpinus Th., ♀, det. Papp J., 1983".

Additional material.

Austria, British Isles (England: V.C. 70; Scotland: V.C.s 83, 85, 88, 89, 97, 103; Finland, France (both Alps and Pyrenees), Italy, Germany, Norway, Romania, Sweden, Switzerland. Specimens in ZJUH, BZL, MRC, MTMA, NMS, RMNH, SDEI, ZIL, ZMUU, ZSSM. This is essentially a montane grassland species, though occurring at low altitudes in northern Europe.

Molecular data.

MRS215 (UK), MRS721 (UK), MRS725 (UK).

Biology.

Collected in (April)May-July. Univoltine, overwintering in the mummy. Reared from the noctuid Cerapteryx graminis (Linnaeus) (9: K.P. Bland, M.J.W. Cock, M.R. Shaw) and from mummies compatible with that (3), and it may be strictly monophagous. The known host overwinters in the egg stage, and feeds on Poaceae near ground level. The tough dark brown mummy is formed on or below the soil surface and seems spectacularly too large for the adult that will emerge from it (Fig. 384 ). It is more or less cylindrical, though with a pronounced lateral keel, and well-lined with silk. The cocoon chamber occupies most of the abdominal segments.

Diagnosis.

Maximum width of hypoclypeal depression 0.4-0.5 × minimum width of face (Fig. 375 ); OOL of ♀ ca twice as long as diameter of posterior ocellus (Fig. 376 ) and distinctly rugose or rugulose; length of 4th antennal segment of ♀ 0.7-0.9 × its width (Fig. 378 ; in ♂ 0.9-1.0 ×); clypeus thick apically and not protruding anteriorly (Fig. 377 ); lobes of mesoscutum densely punctate, interspaces largely smooth and shiny; precoxal area coarsely vermiculate-rugose medially; marginal cell of fore wing of ♀ usually ending rather removed from wing apex (Fig. 368 ); vein 1-CU1 of fore wing 0.5-0.6 × as long as vein 2-CU1 (Fig. 368 ); hind tarsal claws robust (Fig. 380 ) and yellowish or brownish bristly setose; hind femur at least apico-dorsally dark brown or black; inner side of hind tibia of ♀ yellowish; pale males have whole frons and stemmaticum yellowish; palpi dark brown or blackish, rarely brown; 3rd metasomal tergite only antero-laterally reddish or yellowish; 4th and 5th tergites black.

Description.

Redescribed ♀ (RMNH) from Finland (Sb: Leppävirta). Length of fore wing 4.6 mm, of body 5.7 mm.

Head. Antennal segments of ♀ 39, 4th segment 0.8 × longer than wide (Fig. 378 ); antenna as long as fore wing, its subapical segments robust (Fig. 379 ); frons with coarse curved rugae and shiny; OOL 1.9 × diameter of posterior ocellus and rugose; vertex rugose and shiny; face rugose-punctate; clypeus rugose; ventral margin of clypeus rather thick and not protruding forwards (Fig. 377 ); width of hypoclypeal depression 0.5 × minimum width of face (Fig. 375 ); length of eye 1.1 × temple in dorsal view (Fig. 376 ); vertex behind stemmaticum rugose; clypeus below lower level of eyes; length of malar space 0.6 × length of eye in lateral view.

Mesosoma. Mesoscutal lobes moderately punctate, laterally interspaces mainly smooth, medially superficially granulate and rather shiny; precoxal area of mesopleuron coarsely rugose medially and largely smooth posteriorly; remainder of mesopleuron mainly punctate, but dorsally coarsely rugose; scutellum flat, sparsely finely punctate and only anteriorly with lateral carina; propodeum coarsely rugose, medio-longitudinal carina present on anterior half, rounded posteriorly and dorsal part approx. as long as posterior part.

Wings. Fore wing: r 0.3 × 3-SR (Fig. 368 ); marginal cell ends basad of level of apex of 3-M; 1-CU1 horizontal, 0.5 × 2-CU1; r-m 0.6 × 3-SR; 2nd submarginal cell robust (Fig. 368 ), 3-SR 1.3 × as long as 2-SR; cu-a vertical, straight; 1-M slightly curved posteriorly; 1-SR similar to 1-M and medium-sized; surroundings of M+CU1, 1-M and 1-CU1 setose. Hind wing: marginal cell linearly widened, its apical width twice width at level of hamuli (Fig. 369 ); 2-SC+R subquadrate; m-cu short; M+CU:1-M = 27:18; 1r-m 0.7 × 1-M.

Legs. Tarsal claws robust and with only brownish bristly setae (Fig. 380 ); hind coxa largely densely punctate, but dorsally with some rugae; hind trochantellus robust; length of hind femur and basitarsus 3.1 and 3.9 × their width, respectively; length of inner hind spur 0.45 × hind basitarsus.

Metasoma. First tergite rather flattened, 0.8 × as long as wide apically; 1st and 2nd tergites with medio-longitudinal carina and coarsely longitudinally rugose; medio-basal area of 2nd tergite wide triangular and short (Fig. 372 ); 2nd suture deep and crenulate; basal half of 3rd tergite finely longitudinally rugose, remainder of metasoma superficially micro-sculptured; 4th tergite without sharp lateral crease; ovipositor sheath wide, with long setae and apically truncate (Fig. 367 ).

Colour. Orange brown; apical two thirds of antenna, labial palp, patch on hind femur dorso-apically, posterior patch of 2nd tergite and telotarsi, dark brown; head, mesosoma (except side of pronotum postero-dorsally and pair of latero-posterior patches of propodeum), 3rd-7th tergites (except antero-lateral corners of 3rd tergite) black; maxillary palp, basal third of antenna, tegulae and remainder of legs rather pale yellowish brown; veins and pterostigma dark brown; wings distinctly infuscate but hind wing less than fore wing.

Variation. Basal third or half of antenna of ♀ pale yellowish brown; head partly and mesosoma anteriorly of ♀ dark orange brown or both entirely black; 3rd tergite longitudinally striate or rugulose basally (sometimes narrowly so), without curved sculptural elements (Fig. 372 ), except sometimes some weak transverse striae occasionally present at extreme apex. Males are always darker than females; mainly black with legs mainly dark brown or blackish (Fig. 381 ). Antennal segments: ♀ 36(2), 37(4), 38(6), 39(10), 40(6), 41(1); ♂ 47(1), 48(2), 49(2), 50(3), 51(2), 52(4), 53(1), 60(1). On average males have ca 12 more antennal segments than females. Males have 2nd submarginal cell slightly shorter than of females, temple and face long setose, malar space 0.5-0.7 × length of eye in lateral view, apical tergite type 1, rarely type 2, setae rather dense, fringe not observed and probably absent (Fig. 381 ). The superficial granulosity of 3rd tergite and mesoscutum may be absent.

Distribution.

*Austria, British Isles (England, Scotland), Finland, *France, *Ireland, *Italy, *Germany, Norway, *Romania, Sweden, *Switzerland.

New synonymy.

The synonymy of Rogas alpinus Thomson, 1892, with Aleiodes grassator (Thunberg, 1822) is based on direct comparison of the types listed above.

Notes.

Although males of A. carbonaroides are generally easily distinguished from A. grassator through being black, it is possible that lighter forms occur which would be difficult to recognise. Also, females of A. carbonaroides are similar in colour to those of A. grassator . Therefore, specimens collected at low altitude away from northern areas that appear, on other characters, to be A. grassator might well really be A. carbonariodes . See also remarks under A. carbonarius and A. ruficornis .

Figures

Figures 365 - 367. Aleiodes grassator (Thunberg), ♀, Scotland, Beinn Ghlas 365 habitus lateral 366 antenna 367 ovipositor sheath lateral.

Figures 368 - 380. Aleiodes grassator (Thunberg), ♀, Scotland, Beinn Ghlas 368 fore wing 369 hind wing 370 mesosoma lateral 371 mesosoma dorsal 372 metasoma dorsal 373 fore femur lateral 374 hind femur lateral 375 head anterior 376 head dorsal 377 head lateral 378 base of antenna 379 apex of antenna 380 outer hind tarsal claw.

Figures 381 - 384. Aleiodes grassator (Thunberg), ♂, Scotland, Isle of Coll 381 habitus lateral 382 base of antenna 383 apex of antenna 384 mummy of? Cerapteryx graminis (Linnaeus).