Dipogon (Stigmatodipogon) kurokawai Shimizu, 2018

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 : 7-11

2. Dipogon (Stigmatodipogon) kurokawai Shimizu , sp. nov.

( Figs 3 , 4 )

Diagnosis. This species differs from other species by having the apical third of the clypeus, mandible, palpi, scape, pedicel, flagellum, and legs mostly yellowish brown ( Figs 3A, 3B ); the frons densely and finely punctate ( Fig. 3A ); and the gena in dorsal view strongly receding posteriorly ( Fig. 3F ) in the female; and metasomal tergum I not petiolate but gradually narrowed anteriorly in the male ( Fig. 4A ).

Description. (Measurements of the holotype are given in parentheses.) FEMALE. Length: body 4.2–6.8 (5.6) mm; fore wing 4.1–6.2 (4.7) mm. Body black and polished (metasoma more strongly polished than others) ( Fig. 3B ); mesoscutum and scutellum with weak metallic-blue luster. Following yellowish-brown: apical third of clypeus ( Fig. 3A ), mandible (reddish-brown apically), palpi, scape, pedicel, flagellum below and all legs except outer and dorsal faces of coxae ( Fig. 3B ). Following bright brown to castaneous: flagellum dorsally, tegula ( Fig. 3C ), outer and dorsal faces of coxae, lateral and posterior margins of pronotum and metasomal terga, and posterior margins of sterna. Wings ( Fig. 3D ) hyaline with yellowish tint.

Body covered with short grayish- to brownish-white pubescence. Vertex and mesonotum with a few erect pale setae; clypeus preapically and mandible with a few long light-brown setae; metasomal sterna and terga V and VI with light-brown bristles, those on tergum VI being long and very dense.

Frons and dorsum of mesoscutum finely and densely punctate, interspaces alutaceous weakly on frons but distinctly on mesoscutum. Pronotum impunctate and strongly alutaceous. Scutellum and metanotum finely and densely punctate, interspaces almost smooth. Clypeus alutaceous with several setiferous pores subapically, those being smaller than in D. (S.) macrostigmatus . Mesepisternum and lower metapleuron strongly alutaceous. Striae on upper metapleuron weak. Propodeum densely punctate and strongly alutaceous; median groove shallow, broad and indistinct, if any.

Head width 1.1–1.2 (1.1) × length. Vertex in frontal view moderately convex ( Fig. 3A ). Inner orbits slightly convergent above, subparallel below ( Fig. 3A ). UID: MID: LID = 7.0–8.1 (7.6): 10: 9.1–9.5 (9.5). MID 0.57– 0.63 (0.60) × head width. Frons in profile gently convex, slightly protruding anteriorly, a little exceeding level of clypeus ( Fig. 3E ); frontal line impressed only below ( Fig. 3A ). Gena width in profile 0.6–0.8 (0.6) × eye width ( Fig. 3E ). Ocellar triangle acute-angled ( Fig. 3F ), slightly raised. POL: OOL = 1: 0.72–1.8 (0.94). Clypeus as broad as LID ( Fig. 3A ), its width 2.3–2.7 (2.6) × length, convex medially; apicolateral corner broadly rounded; apical rim slightly depressed and alutaceous; apical margin broadly straight. Malar space very short. Flagellomere I length 1.3–1.4 (1.3) × flagellomere II length, 4.5–5.9 (5.2) × its width, 0.74–1.0 (0.84) × UID.

Pronotum slightly depressed near posterior margin, latter being obtusely angulate medially ( Figs 3C, 3F ); anterior declivity not distinctly differentiated from dorsum; shoulder scarcely bulging. Discs of scutellum and metanotum slightly convex above level of mesoscutum. Metapostnotum length 0.1–0.2 (0.2) × metanotum length at midline. Propodeum length 0.85–1.1 (1.0) × width, gently and evenly convex in profile ( Fig. 3B ); medial groove shallow and indistinct, if any.

Mid tibiae with few minute spines laterally. Hind tibia devoid of spines laterally. Longer spur of hind tibia 0.41–0.49 (0.43) × hind tarsomere I length. Tarsomere V not enlarged, hind tarsomere V length 1.3–1.8 (1.4) × hind tarsomere IV length, its width 1.1–1.3 (1.2) × hind tarsomere IV width.

Fore wing shown in Fig. 3D . Pterostigma length 1.6–2.1 (1.8) × SMC2 length, its width 0.74–0.96 (0.83) × SMC2 width. SMC2 length 1.3–1.8 (1.8) × width, narrowed on vein Rs by 0.67–0.80 (0.73) × its own length on vein M, receiving crossvein 1m-cu at basal 0.42–0.59 (0.45). SMC3 length 1.1–1.3 (1.2) × width, 0.91–1.3 (0.98) × SMC2 length on vein M, 0.58–0.93 (0.79) × SMC2 length on vein Rs, narrowed on vein Rs by 0.48–0.60 (0.59) × its own length on vein M, receiving crossvein 2m-cu at basal 0.27–0.50 (0.29). Crossvein 2rs-m strongly curved. Crossvein 3rs-m elbowed posteriorly.

Metasomal tergum I with long petiole ( Fig. 3C ). Tergum II width 0.83–0.99 (0.88) × head width.

Description. MALE. Length: body 4.4–5.1 mm; fore wing 3.9–4.5 mm. Body black. Mandible dark brown to black basally, yellowish- to bright-brown medially, reddish-brown apically. The following more or less ferruginous: apical third of clypeus ( Fig. 4B ), antenna below (sometimes yellowish-brown), lateral and posterior margins of pronotum and metasomal terga, tegula and posterior margins of sterna. Legs mostly dark brown; coxae apically, trochanters below and fore tibia (sometimes mid tibia below also) yellowish-brown; tarsomeres I–IV ferruginous apically.

Vertex, gena, postgena, dorsum of mesonotum, propleuron, mesosternum, coxae and metasomal sterna with a few grayish-white to brown setae; a pair of setae on vertex near inner orbits and setae on postgena longer than others; clypeus apically and mandible with a few long light-brown bristles arising from rather large pores.

Frons, vertex and dorsa of meso- and metanota densely punctate and alutaceous (scutellum and metanotum weakly alutaceous). Pronotum impunctate and strongly alutaceous (appearing minute dense setiferous pores seen from some directions). Mesepisternum and lower metapleuron minutely reticulo-rugulose. Propodeum irregularly punctate and strongly alutaceous with indistinct median groove.

Head width in frontal view 1.1–1.2 × length. UID: MID: LID = 8.0–8.6: 10: 8.7–9.1. MID 0.59–0.61 × head width. Ocellar triangle right- to obtuse-angled ( Fig. 4C ). POL: OOL = 1: 0.74–1.0. Clypeus width 2.3–2.4 × length. Gena in dorsal view more roundly receding than in female (compare Fig. 4C with Fig. 3F ), its width in profile 0.6–0.7 × eye width ( Fig. 4D ). Flagellomere I length 0.95–0.98 × flagellomere II length, 2.5–2.9 × its width and 0.58–0.68 × UID.

Pronotum with shoulder roundly receding anteriorly ( Fig. 4C ); sides overall convergent anteriorly. Discs of scutellum and metanotum more strongly raised than in female ( Fig. 4E ). Metapostnotum length 0.2–0.3 × metanotum length at midline. Propodeum length 0.85–0.87 × width.

Fore wing shown in Fig. 4F . Pterostigma length 1.8 × SMC2 length, its width 0.82–0.87 × SMC2 width. SMC2 length 1.5 × width, narrowed on vein Rs by 0.81–0.82 × its own length on vein M, receiving crossvein 1m-cu at basal 0.62–0.64. SMC3 length 1.2 × width, 1.0 × SMC2 length on vein M, 0.47–0.53 × SMC2 length on vein Rs, narrowed on vein Rs by 0.38–0.43 × its own length on vein M, receiving crossvein 2m-cu at basal 0.30–0.38. Vein M weakly pigmented posteriorly to junction with crossvein 2rs-m.

Mid and hind tibiae with a few small spines laterally. Longer spur of hind tibia 0.61–0.66 × hind tarsomere I length. Tarsal claws with triangular tooth preapically, that being as stout as apex of main shaft.

Metasomal sternum II with transverse groove slightly arcuate, situated close to posterior margin of tergum I. A pair of lateral hooks on sternum VI tapering and directed outward apically with several erect setae basally ( Fig. 4H ). Posterior margin of sternum VI between hooks slightly and arcuately emarginate. Exposed portion of SGP ( Fig. 4H ) with fluke on side, that being directed posterolaterally, and with long dense setae subapically and apically; apical margin subangularly produced. Genitalia ( Figs 4I, 4J ): paramere extending slightly beyond apex of aedeagus with long dense setae on outer face from base to apex.

Material examined. Holotype, ♀, JAPAN, Honshu, Hatogayu, Ohno-shi , Fukui Pref., 10.vii.1991 (H. Kurokawa) [ NSMT] . Paratypes. JAPAN. Hokkaido: 1♀, Okuhoronai, Ômu-chô, 2009 (A. Ueda); 1♀, Maruyama , Sapporo , 8.viii.2001 (T. Yoshida). Honshu: 1♀, 1200 m, Asahi-kousen, Mt. Asahi-dake , Asahi-cho , Yamagata Pref., 10.viii.2000 (R. Oomuta); 1♀, same locality and collector, 17.viii.2001; 1♀, 1000 m beech forest, Mt. Hakase , Showa , Fukushima Pref. , 1–28.vi.1998, Malaise Trap (T. Muroi); 1♀, Hinoemata , Fukushima, 27.viii.1979 (T. Nambu); 1♀, Hayashidani, Izumi-mura , Fukui Pref., 30.ix.1995 (C. Nozaka); 3♀ (R0603-0902– 0904) 1♂ (R0603-1501), Mt. Norikura-dake , Shirahone, Azumi-mura , Nagano Pref. , 5.v.2006 (Y. Nishimoto); 1♀, Satsura, Izumi-mura , Fukui Pref. , 15.x.1987 (Y. Haneda); 1♀, Ohtani, Izumi-mura , Fukui Pref., 3.x.1995 (C. Nozaka); 1♀, Kamiuchinami, Ohno-shi , 4.x.1982 (T. Murota); 1♀, Nakabora, Ohno-shi , Fukui Pref., 11.x.2001 (H. Kurokawa); 1♀, same locality, 17.x.2002 (C. Nozaka); 1♂, Mt. Akausagi-yama , Ohno-shi , Fukui Pref. , 7.ix.1975 (Y. Haneda). All paratypes are deposited at NSMT .

Etymology. Named after Mr. H. Kurokawa, the provider of the holotype specimen.

Distribution. Japan (Hokkaido, Honshu).

Biology. On 3, 4 June 2005, Y. Nishimoto installed 55 bamboo cane traps (number of canes per trap: 15) in broad-leaved forests on the sides of Mt. Norikura-dake (1,445–1693 m above sea level) in Nagano and Gifu Prefectures, Central Honshu. These traps were collected in autumn of the same year. On 5 May 2006, four individuals of this species emerged from two of the bamboo canes (4–7 mm in diameter) that were placed in a beech forest adjacent to a fir forest at an altitude of 1,642 m of Shirahone, Azumi-mura, Nagano Pref. Because these nests were constructed in the same trap, there is a strong probability that the identical female wasp utilized these canes. One of the nests (#R603-09) had four brood cells in the inner section and three empty cells in the outer section, with cell partitions and a closing plug made of mud and various amount of wood powder. Three females (R0603-0902–0904) emerged from the second to fourth brood cells. The other nest (#R603-15) had only one brood cell, from which a male (R0603-1501) emerged. The nest did not have a cell partition or a closing plug of mud, but wood powder.

Figures

FIGURE 3. Dipogon (Stigmatodipogon) kurokawai, sp. nov., holotype, ♀. A. Head, frontal view. B. Whole body, lateral view. C. Mesosoma and metasomal tergum I basally, dorsal view. D. Wings. E. Head, lateral view. F. Head, dorsal view and pronotum, dorsolateral view. Scale bars: 1 mm for B, 0.5 mm for others.

FIGURE 4. Dipogon (Stigmatodipogon) kurokawai, sp. nov., paratype, ♂ from Yamagata Pref., Honshu, Japan. A. Metasomal tergum I basally, dorsal view. B. Head, frontal view. C. Head, pronotum and scutum, dorsal view. D. Head and pronotum anteriorly, lateral view. E. Head and mesosoma, lateral view. F. Wings. G. Flagellomeres III–XI, lateral view. H. Metasomal sternum VI and SGP apically, ventral view. I. Genitalia, dorsal view. J. Same, ventral view. Scale bars: 0.1 mm for A, H–J, 0.5 mm for others.