Dipogon (Stigmatodipogon) petiolatus Lelej, 1986

Shimizu, Akira, Lelej, Arkady S., Loktionov, Valery M., Nishimoto, Yutaka & Endo, Tomoji, 2018, Revision of the subgenus Stigmatodipogon Ishikawa of the genus Dipogon Fox (Hymenoptera: Pompilidae: Pepsinae), Zootaxa 4514 (1), pp. 1-22 : 15-18

5. Dipogon (Stigmatodipogon) petiolatus Lelej, 1986

( Figs 7 , 8 )

Dipogon (Stigmatodipogon) petiolatus Lelej, 1986: 805 , ♀ ♂ (holotype, ♀, Russia, Primorskii krai, Ussurijsky Natural Reserve, 16.viii.1974 (A. Lelej) [ZISP], examined); Lelej 1995: 227, 229, ♀ ♂; Loktionov 2011: 85.

Dipogon petiolatus: Loktionov & Lelej 2010: 54 .

Stigmatodipogon petiolatus: Lelej & Loktionov 2012a: 414 (part.); 2012b: 11; Loktionov & Lelej 2014: 158, ♀ ♂.

Diagnosis. This species differs from other species by having the frons densely punctate, with the interspaces alutaceous and weakly polished ( Fig. 7A ); the gena in dorsal view not strongly receding ( Fig. 7B ) in the female; and the pterostigma as wide as or slightly wider than SMC2 ( Fig. 8A ); the apical margin of the clypeus slightly emarginate medially; the hind tarsal claw edentate or with minute tooth preapically, which is much weaker than the apex of the main shaft; and metasomal tergum I parallel-sided basally ( Fig. 8B ) in the male.

Redescription. (Measurements of the holotype are given in parentheses.) FEMALE. Length: body 3.9–5.8 (4.3) mm; fore wing 3.8–5.1 (4.0) mm. Body black and polished ( Fig. 7C ). Mandible dark brown on basal half, yellowish-brown on apical half, reddish-brown at apex. Following more or less ferruginous: antenna (brighter below than above), lateral margin of pronotum, tegula, lateral and posterior margins of metasomal terga and posterior margins of metasomal sterna. Palpi light brown. Legs mostly bright- to dark-brown; fore tibia and all tarsi more or less bright- to yellowish-brown, except for dark brown tarsomeres V. Wings hyaline; fore wing distinctly bifasciate ( Fig. 7C ).

Body with short greyish- or brownish-white pubescence, that being dense on lower frons, mesepisternum, lower metapleuron, mesosternum and coxae. Vertex and mesonotum with a few fine brown setae; clypeus preapically and mandible with long stout bristles arising from rather large pores; metasomal sterna and tergum V with sparse brown bristles; tergum VI with long dense brown bristles.

Frons ( Fig. 7A ), vertex ( Fig. 7B ) and dorsum of mesoscutum ( Fig. 7E ) densely punctate and alutaceous. Clypeus strongly alutaceous with several large, setiferous pores preapically. Pronotum alutaceous with minute dense setiferous pores. Scutellum and metanotum densely punctate, interspaces almost smooth. Mesepisternum and lower metapleuron strongly alutaceous; upper metapleuron weakly striate and punctate with posterior margin impunctate and smooth. Propodeum irregularly punctate and alutaceous.

Head width 1.1–1.2 (1.1) × length, 1.3–1.4 (1.4) × pronotal dorsum width. Vertex in frontal view moderately convex ( Fig. 7A ). Inner orbits convergent above, subparallel below ( Fig. 7A ). UID: MID: LID = 7.1–7.7 (7.2): 10: 8.9–9.4 (9.4). MID 0. 59–0.64 (0.60) × head width. Frons in profile gently convex, slightly protruding anteriorly, exceeding level of clypeus ( Fig. 7D ); frontal line shortly impressed only below. Gena width in profile 0.7–0.8 (0.7) × eye width ( Fig. 7D ). Ocellar triangle acute-angled, slightly raised ( Fig. 7B ). POL: OOL = 1: 0.78–1.0 (0.95). Vertex with oblique shallow impressed line from posterior end of lateral ocellus to eye. Clypeus as broad as LID, its width 2.4–2.7 (2.6) × length, convex medially; apicolateral corner subangulate; apical rim depressed and narrowed medially, roundly ridged just anteriorly to it; anterior margin almost straight medially. Malar space very short and linear. Flagellomere I length 1.3–1.4 (1.3) × flagellomere II length, 4.6–5.3 (5.0) × its width, 0.75–0.92 (0.82) × UID.

Pronotum with anterior declivity barely differentiated from dorsum; shoulder weakly bulging ( Fig. 7E ); posterior margin with obtuse median angulation. Discs of scutellum and metanotum slightly convex above level of mesoscutum. Metapostnotum length 0.1–0.2 (0.1) × metanotum length at midline. Propodeum length 0.75–0.90 (0.82) × width, in profile evenly convex (declivity not differentiated from dorsum) ( Fig. 7C ), usually with shallow median groove.

Mid tibia with a few minute spines laterally. Hind tibia devoid of spines laterally. Longer spur of hind tibia 0.44–0.49 (0.48) × hind tarsomere I length. Tarsomere V slightly enlarged, hind tarsomere V length 1.3–1.6 (1.6) × hind tarsomere IV length, its width 1.1–1.3 (1.3) × hind tarsomeres IV width.

Fore wing shown in Fig. 7C . Pterostigma length 1.7–2.2 (2.2) × SMC2 length, its width 0.72–0.94 (0.83) × SMC2 width. SMC2 length 1.2–1.7 (1.2) × width, narrowed on vein Rs by 0.63–0.78 (0.78) × its own length on vein M, receiving crossvein 1m-cu at basal 0.45–0.60 (0.51). SMC3 length 1.1–1.8 (1.2) × width, 1.0–1.6 (1.3) × SMC2 length on vein M, 0.68–1.1 (0.83) × SMC2 length on vein Rs, narrowed on vein Rs by 0.39–0.63 (0.50) × its own length on vein M, receiving crossvein 2m-cu at basal 0.22–0.35 (0.29). Crossvein 2rs-m strongly curved and oblique to vein M. Crossvein 3rs-m arcuate or elbowed.

Metasomal tergum I with long petiole ( Fig. 7F ). Tergum II width 0.82–0.93 (0.85) × head width.

Redescription. MALE (paratype). Length: body ca. 4.0 mm; fore wing 3.0 mm. Body black. Mandible darkbrown on basal half, yellowish-brown on apical half, reddish-brown at apex. Tegula light brown. Following dark brown: clypeus apically and antenna above. Following ferruginous: antenna below, lateral and posterior margins of pronotum and metasomal terga, and posterior margins of metasomal sterna. Legs dark- to bright-brown (fore tibia and tarsomeres I–IV bright brown; tarsomere V dark brown).

Metasomal sterna with a few very short pale setae.

Head and dorsa of pronotum and mesoscutum impunctate and strongly alutaceous. Dorsa of scutellum and metanotum punctate, interspaces weakly alutaceous. Propodeum strongly and irregularly punctate and alutaceous. Metasomal terga impunctate and coarsely alutaceous.

Head crushed ( Fig. 8C ), hence no available for measurement. Flagellomere I length 1.0 × flagellomere II length, 2.6 × its width.

Pronotum with shoulder barely bulging; anterior declivity broad and vertical ( Fig. 8D ), weakly differentiated from dorsum. Metapostnotum length 0.17 × metanotum length at midline, arcuately broadened on each side of midline. Propodeum length 0. 85 × width, gently convex ( Fig. 8D ) without median groove.

Fore wing shown in Fig. 8A . Pterostigma length 2.6 × SMC2 length, its width 1.1 × SMC2 width. SMC2 length 1.4 × width, narrowed on vein Rs by 0.68 × its own width on vein M, receiving crossvein 1m-cu at basal 0.52. SMC3 length 1.3 × width, 1.4 × SMC2 length on vein M, 1.1 × SMC2 length on vein Rs, narrowed on vein Rs by 0.53 × its own length on vein M, receiving crossvein 2m-cu at basal 0.35.

Longer spur of hind tibia 0.57 × hind tarsomere I length. Tarsal claws edentate, tapering toward apex or with minute tooth preapically.

Metasomal sternum II with transverse groove angulate medially. A pair of claw-like lateral hooks on sternum VI tapering and curved outward; posterior margin of sternum VI between hooks gently arcuate. Exposed portion of SGP ( Fig. 8E ) with fluke on side, that being directed posterolaterally, and with dense setae subapically and apically; apical margin triangularly produced. Genitalia ( Fig. 8F ): paramere slightly extending beyond apex of parapenial lobe with long dense setae on outer face and apical half.

Material examined. Paratypes. RUSSIA. Primorskij krai: 1♀, Ussurijsky Natural Reserve, Peishula, 29.iii.1972 (Arefin) [ IBSS]; 2♂, Lazovskii Natural Reserve , Benevskoe , 25.iv.1983 (T. Romankova) [ IBSS]. Irkutsk Prov.: 1♀, Southern Baikal , Kadilnaya Pad, 12.viii.1983 (P. Nemkov) [ IBSS]. Other material . RUSSIA. Primorskij krai: 1♀, Upper part of Verhnyaya Sokolovka River, 20.viii.2008 (V. Loktionov) [ IBSS]; 1♀, Dersu, 27.viii.1991 (P. Nemkov) [ IBSS]; 16♀, Ussurijsky Natural Reserve , 7, 9.ix.1992 (A. Lelej) [ IBSS]; 1♀, same locality and collector, 4.vii.1993 [ IBSS] .

Distribution. Russia: Eastern Siberia (Irkutsk Prov.) and Far East (Primorskij krai).

Biology. The holotype specimen is pinned with a subadult male spider of Araneidae .

Figures

FIGURE 7. Dipogon (Stigmatodipogon) petiolatus, holotype, ♀. A. Head, frontal view. B. Head and pronotum, dorsal view. C. Whole body, lateral view. D. Head and pronotum, lateral view. E. Pro- and mesonota, dorsal view. F. Metasomal tergum I, dorsal view. Scale bars: 1 mm for C, 0.1 mm for F, 0.5 mm for others.

FIGURE 8. Dipogon (Stigmatodipogon) petiolatus, paratype, ♂. A. Fore wing. B. Metasomal tergum I, dorsal view. C. Head, dorsal view. D. Mesosoma and metasoma, lateral view. E. Metasomal sterna VII and SGP, ventral view. F. Genitalia, ventral view. Scale bars: 1 mm for D, 0.1 mm for B, 0.25 mm for E, 0.5 mm for others (E, F from Loktionov & Lelej 2014).