Nipponodipogon Ishikawa, 1965

Shimizu, Akira, Lelej, Arkady S. & Loktionov, Valery M., 2015, Revision of the Palaearctic brood parasitic genus Nipponodipogon Ishikawa, 1965 of spider wasps (Hymenoptera: Pompilidae: Pepsinae), Zootaxa 3948 (3), pp. 497-520 : 498-499

Genus Nipponodipogon Ishikawa, 1965

Nipponodipogon Ishikawa, 1965a: 89 (as subgenus of Dipogon Fox, 1897 ). Type species: Dipogon (Nipponodipogon) iwatai Ishikawa 1965 , by original designation.

Nipponodipogon: Lelej & Loktionov 2012a: 413 (as genus).

Species included. The genus includes seven species, which are distributed in the East Palaearctic region: Nipponodipogon hayachinensis ( Ishikawa, 1968) , N. iwatai (Ishikawa, 1965) , N. kurilensis ( Lelej, 1986) , N. mandibularis (Ishikawa, 1965) , N. nagasei (Ishikawa, 1965) , N. rossicus ( Lelej, 1986) and N. sudai Shimizu , sp. nov.

Diagnosis. This genus differs from other genera of the Dipogon genus-group by having (1) the maxillary cardo with a few light brown bristles; (2) the antenna short, stout and thickened toward the middle of the flagellum (fusiform); F1 less than 3 × as long as thick in the female; (3) the supra-antennal area of the frons produced anteriorly into a frontal ledge overhanging the antennal radicle ( Figs 6 B, 7B); (4) the apical margin of the labrum not or slightly emarginated medially ( Figs 1 A, 2A, 3A, 4A, 5A, 6A, 7A, 8A–B); (5) the mesepisternum strongly convex above the level of the lateral face of the pronotum and metapleuron; (6) the metapostnotum narrow and practically linear, deeply sunken between the metanotum and propodeum ( Figs 1 C, 2C, 3C, 4C, 5C, 6D, 7D); and (7) crossvein cu-a of the hind wing short and almost straight, forming an obtuse angle with vein 1A in both sexes ( Figs 9 A–B, D–E, G, I–K).

Description (for other characteristics except for the following, see the generic characteristics of Dipogon provided by Shimizu and Ishikawa (2002)). FEMALE. Small-sized, body length 4–8 mm. Body robust. Legs rather short, hind femur not extending beyond apex of metasoma. Wings transparent with brownish tint; fore wing with two fuscous fasciae ( Fig. 9 ).

Body with short, weak, gray pubescence. Setae on body scanty; vertex with one or two long erect setae on each side along inner orbit; clypeus preapically, labrum apically, mandible, T5, T6 and S6 with comparatively long bristly setae.

Head and mesosoma finely punctate (propodeum strongly punctate anteriorly, transversely rugulose posteriorly). Metasoma minutely punctate.

Antennal socket separated from upper margin of clypeus by much less than half of its diameter. Antennocular line (anterior margin of head from antennal socket to eye in dorsal view) steeply inclined ( Figs 1 B, 2B, 3B, 4B, 5B, 6C, 7C). Eye much narrower than half of MID. Clypeus as wide as LID, with large setiferous pores preapically.

Pronotum short and transverse; anterior declivity short but broad. Discs of scutellum and metanotum fairy flattened. Pterostigma normal-sized, much lower than SMC2. Fore femur not swollen, compared with mid femur. Outer apicoventral corner of hind femur rounded ( Fig. 2 D) or produced triangularly ( Fig. 7 E). Mid and hind tibiae with short but strong spines dorsally.

T1 petiolate, i.e., T1 narrowed immediately behind articulation with propodeum ( Figs 3 D, 8E) or not petiolate ( Figs 6 E, 8C, D). S2 with transverse groove. Sting scarcely curved upward.

MALE. Body slenderer than female. Body more strongly punctate than in female. Antenna slightly thickened medially, with F3–11 triangularly produced beneath. Mandible with tooth on its inner margin, that being as stout as apical point. Discs of scutellum and metanotum more strongly raised and compressed laterally than in female. Exposed portion of subgenital plate small and compressed laterally ( Figs 2 F, 5E). Genitalia with basal hooklets double ( Figs 2 H, 5G, 6J, 7J).

Distribution. Japan (Hokkaido, Honshu, Kyushu) and Russian Far East (Kuril Il.: Kunashir, Primorskiy Terr.).

Etymology. The generic name Nipponodipogon originates from 'Nippon', Japan and 'Dipogon', generic name in Pompilidae , with reference to the country where it has been found.

Biology. According to Shimizu et. al (2012), Nipponodipogon nagasei brood-parasitizes Deuteragenia sperconsa ( Shimizu & Ishikawa, 2002), D. conspersa ( Pérez, 1905) , D. inconspersa ( Shimizu & Ishikawa, 2002) and D. bifasciata ( Geoffroy, 1785) . Nipponodipogon iwatai brood-parasitizes D. sperconsa , D. conspersa , D. romankovae ( Lelej, 1986) and Auplopus carbonarius ( Scopoli, 1763) . They revealed these, based on the following evidence obtained from their trap nests: (1) bamboo stems that produced both N. nagasei or N. iwatai and other pompilid species were frequent (about 50 % of all bamboo stems produced either N. nagasei or N. iwatai ); (2) when Nipponodipogon wasps occur with Deuteragenia or Auplopus Spinola, 1841 wasps in bamboo stems, the cells producing Nipponodipogon were sometimes interspersed irregularly among those producing the other wasps; (3) cell partitions in bamboo stems from which N. nagasei or N. iwatai emerged sometimes had a hole 1.4–1.9 mm in diameter, the sizes of which are slightly greater than their head height (the holes were not holes through which emerging wasps got out of their cells, because the cocoons were taken out of the cells and were reared in small glass vials until their emergence); and (4) in the nests which produced both N. iwatai and A. carbonarius , adults of both species emerged from barrel-shaped mud cells with numerous papillary projections on the outer surface, which were typical of A. carbonarius ’s cells. It is surprising that in N. nagasei the female routinely laid up to five eggs on a single host spider, all of which might have developed into adult wasps without larval cannibalism. Since almost all pompilids previously studied lay only one egg on a prey spider, this behavioral trait is considered to be highly specialized to brood parasitism.

Figures

FIGURE 1. Nipponodipogon hayachinensis, ♀, type locality. A. head, frontal view; B. head, dorsal view; C. propodeum, lateral view; D. outer claw of left hind tarsus. Scale lines: 0.5 mm.

FIGURE 2. Nipponodipogon iwatai. (A – E, holotype, ♀; F – I, ♂, Japan). A. head, frontal view; B. head, dorsal view; C. mesosoma, lateral view; D. apical portion of left hind femur, outer view; E. S 1 and S 2, ventral view; F. S 6 and subgenital plate, ventrolateral view; G, subgenital plate, lateral view; H, genitalia, ventral view; I. genitalia, dorsal view. Scale lines: 0.5 mm.

FIGURE 3. Nipponodipogon kurilensis, holotype, ♀. A. head, frontal view; B. head, dorsal view; C. mesosoma, lateral view; D. T 1, dorsal view; E. S 1 and S 2, ventrolateral view. Scale lines: 0.5 mm.

FIGURE 6. Nipponodipogon rossicus. (A – F, holotype, ♀; G – J, paratype, ♂, Russian Far East). A. head, frontal view; B. head, lateral view; C, G. head, dorsal view; D. mesosoma, lateral view; E. T 1, dorsal view; F. S 1 and S 2, ventral view; H. S 6, ventral view; I. subgenital plate, lateral view; J. genitalia (left half, dorsal view; right half, ventral view). Scale lines: 0.5 mm.

FIGURE 7. Nipponodipogon sudai sp. nov. (A – F, holotype, ♀; G – K, paratype, ♂, Japan). A. head, frontal view; B. head, lateral view; C, G. head, dorsal view; D. mesosoma, lateral view; E. apical portion of left hind femur, outer view; F. S 1, ventrolateral view; H. S 6, ventrolateral view; I. subgenital plate, lateral view; J. genitalia (left half, dorsal view; right half, ventral view); K. aedeagus and parapenial lobe, dorsal view. Scale lines: 0.5 mm.

FIGURE 9. Nipponodipogon, fore and hind wings. A. N. hayachinensis, ♀, Japan; B. N. iwatai, holotype; C, D. N. kurilensis, holotype; E. N. mandibularis, holotype; F, G. N. nagasei, holotype; H, I. N. rossicus, holotype. J. H. sudai sp. nov., paratype, ♀, Japan; K. H. sudai, paratype, ♂, Japan. Scale lines: 1.0 mm.