Megaxyela togashii Shinohara, 1992

Stephan M. Blank, Katja Kramp, David R. Smith, Yuri N. Sundukov, Meicai Wei & Akihiko Shinohara, 2017, Big and beautiful: the Megaxyela species (Hymenoptera, Xyelidae) of East Asia and North America, European Journal of Taxonomy 348, pp. 1-46 : 30-33

Megaxyela togashii Shinohara, 1992

Figs 10A–J , 11H , 12H , 13F

Megaxyela togashii Shinohara, 1992: 789–792 , 794, figs 1C–D, 2C–D, 2F–G, 4B, 4D, 5A–C (♀ ♂, type locality: Japan, Honshu, Ishikawa Prefecture, Yoshinodani-mura, Senami).

Megaxyela togashii – Tanaka 1999: 57 (record from Japan, Honshu, Yamaguchi Prefecture). ― Yamada 2000: 53 (record from Japan, Honshu, Aomori Prefecture). ― Naito et al. 2004: 6 (record from Japan, Honshu, Hyogo Prefecture). ― Shinohara 2006: 157 (record from Japan, Shikoku, Ehime Prefecture). ― Shinohara et al. 2017: 222–230 (record from Japan, Hokkaido, larva, life history).

Megaxyela gigantea – Watanabe 1992: 8 (record from Japan, Honshu, Okayama Prefecture). [See Ko (1969), Smith (1978) and Shinohara (1992) for numerous additional references].

Material examined or reported in literature

JAPAN: 6 larvae, Hokkaido, Ashoro town, Asahi , 43.233° N, 143.500° E, 100 m alt., 30 Jun. 2010, A. Shinohara and H. Hara leg., on Juglans ailanthifolia, including DEI-GISHym 30805–30807 ( NSMT) ( Shinohara et al. 2017) ; 2 larvae, Hokkaido, Ashoro town, Nishikitoushi , 43.383° N, 143.367° E, 345 m alt., 1 Jul. 2010, A. Shinohara and H. Hara leg., on Juglans ailanthifolia,including DEI-GISHym 30804 (NSMT) ( Shinohara et al. 2017); 1 larva, Hokkaido, Shintoku town , 43.083° N, 142.817° E, 200 m alt., 26 Jun. 2011, H. Hara leg. ( Shinohara et al. 2017); 1 larva , Hokkaido, Sapporo city, Misumai , 42.950° N, 141.250° E, 160 m alt., 19 Jun. 2013, H. Hara leg. ( Shinohara et al. 2017); 1 larva, Hokkaido, Sapporo city, Koganeyu , 42.967° N, 141.200° E, 250 m alt., 19 Jun. 2013, H. Hara leg. (not preserved) ( Shinohara et al. 2017); 1 ♀, Honshu, Aomori Prefecture, Minami-Hakkoda , 40.60° N, 140.84° E, 30 May 1999, M. Yamada leg., M. Yamada coll. ( Yamada 2000; reliable record, not re-examined); 1 ♂, paratype, Honshu, Hiroshima Prefecture, Kamiyama, Kure , 34.28° N, 132.57° E, 7 May 1933, coll. Nakanishi (UOP) ( Shinohara 1992); 1 ♀, Honshu, Hyogo Prefecture, Sayo-gun, Mikazuki-cho , Mihara , 34.95° N, 134.42° E, 18 May 1995, T. Sasai leg., DEI-GISHym 22353 (KUEL) ( Naito 2004) ; 1 ♀, Honshu, Hyogo Prefecture, Shiso-gun, Haga-cho , Akasai-keikoku , 35.23° N, 134.48° E, 680 m alt., 8 Jun. 1986, T. Morita leg., T. Morita coll. ( Naito et al. 2004; reliable record, not re-examined); 1 ♀, holotype, Honshu, Ishikawa Prefecture, Yoshinodani-mura, Senami , 36.32° N, 136.65° E, 29 Jun. 1964, I. Togashi leg., DEI-GISHym 22352 (NSMT) (distal articles of right antenna glued to collecting label; Shinohara 1992); 5 larvae, 1 egg, Honshu, Hyogo prefecture, Tatsuno city, Shingu town , 34.867° N, 134.567° E, 35 m alt., 30 Apr. 2016, on Juglans ailanthifolia, A. Shinohara leg., including Shinohara’s sample numbers 761–764 (NSMT) ( Shinohara et al. 2017) ; 1 ♀, Honshu, Okayama Prefecture, Kawakami-gun, Bichu-cho , Nishiyuno , 34.80° N, 133.47° E, 5 May 1986, A. Watanabe leg.,A. Watanabe coll. ( Watanabe 1992, misidentified as M. gigantea ); 1 ♂, Honshu, Okayama Prefecture, Tamagashi, Okayama-shi , 34.72° N, 133.97° E, 10 m alt., 3 May 2005, A. Shinohara leg., DEI-GISHym 22354 , used for barcoding (NSMT) ( Shinohara 2006); 1 ♂, as preceding, except 2 May 2006, DEI-GISHym 22521 used for barcoding (NSMT) ( Shinohara 2006); 1 specimen, Honshu, Yamaguchi Prefecture, Kuga-gun, Nishiki-machi, Mt. Jakuchi-san, Sancho [= summit] , 34.47° N, 132.05° E, 1337 m alt., 6 Jun. 1993, K. Tanaka leg., K. Tanaka coll. ( Tanaka 1999, reliable record, not re-examined); 2 larvae, Shikoku, Ehime prefecture, Kihoku town , Narukawa-keikoku , 33.200° N, 132.617° E, 650 m alt., 5 May 2016, on Juglans ailanthifolia, A. Shinohara leg., Shinohara’s sample numbers 765–766 (NSMT) ( Shinohara et al. 2017) ; 1 ♀, Shikoku, Ehime Prefecture, Narukawa-keikoku, Kihoku-cho , 33.20° N, 132.62° E, 550 m alt., 8 May 2006, A. Shinohara leg. (NSMT) ( Shinohara 2006).

Description

See Shinohara (1992) and Figs 10A–C, G–H , 11H (ovipositor sheath).

Female

Ovipositor about 2.4 mm long, weakly curved ventrally, valvula 1 and 2 with bulbous areas close to middle, without ctenidia ( Fig. 12H ). Body 12.6 mm, fore wing 15.4 mm long. Black spot on face extending lateroventrally to mid-level of toruli, medially continuous with predominantly black subantennal area (holotype with two small brown spots) or subantennal area yellow (specimen from Mihara). Pulvilli absent on article 1 of metatarsus, present on articles 3–4, presence ambiguous for article 2, on article 4 pulvillus 70 µm long.

Male (specimen from Tamagashi, DEI-GISHym 22354, Fig. 10D–F, I–J )

Body 12.0 mm, fore wing 13.4 mm. Antennal filament 1.3 mm long, with 8–9 articles. Valviceps distally parabolically rounded, basal quarter of upper side expanded to a round lobe weakly coiled laterally, section of upper edge distal of lobe straight or with shallow elevations, close to the lobe with irregular teeth, in medial 0.3–0.8 with numerous small teeth. Distal 0.7 of valviceps with long setae, dense in medial and lower portion of middle ( Fig. 13F ).

Host plant

Ten larvae identified by their COI sequences as M. togashii were found feeding on Juglans ailanthifolia ( Shinohara et al. 2017). In addition, three adults were collected from trees of this walnut species ( Shinohara 2006, citing the synonym J. mandshurica Maxim. ssp. sieboldiana [Maxim.] Kitamura). Japanese Wingnut, Pterocarya rhoifolia Sieb. & Zucc., possibly represents an additional larval host ( Shinohara et al. 2017). Takeuchi’s (1949) record of Juglans for M. ‘ gigantea ’ (= M. togashii ) in a checklist of the host plants of Japanese sawflies most likely concerns Saito’s (1941) rearing record for M. gigantea from Korea (see also Takeuchi 1938).

Remarks

Megaxyela togashii is the correct name for the Japanese species, which has been called M. gigantea by Takeuchi (1937), Togashi (1965) and subsequent authors up to Shinohara (1992). This species is most similar to M. pulchra sp. nov. in structure and color. See Remarks there for differentiation of these two species.

The clade including two genetically studied adults from Honshu, which were collected on the same site, is supported by a bootstrap of 100%. The maximum intraspecific variation is 1.4%. Under a wider geographical scope, Shinohara et al. (2017) observed a variation of 4.3% after inclusion of ten larvae from Hokkaido, Honshu and Shikoku. Even then the intraspecific variation is smaller than the minimum pairwise distance of 8.0% to the nearest neighbor, M. pulchra sp. nov.

Figures

Fig. 10. Megaxyela togashii Shinohara, 1992, ♀, holotype, DEI-GISHym 22352 (NSMT); ♂, 22354, (NSMT). A – B. Habitus dorsal / lateroventral (♀). C. Head frontal (♀). D – E. Habitus dorsal / lateroventral (♂). F. Head frontal (♂). G – H. Metatarsus lateral / ventral (♀). I – J. Metatarsus lateral / ventral (♂). Arrows in Fig. 10 B and 10 F indicate dark spots of abdominal sterna, arrowheads in H and J indicate minute pulvilli.

Fig. 11. Species of Megaxyela Ashmead, 1898, ovipositor sheaths. A. M. euchroma Blank, Shinohara & Wei sp. nov. (holotype, DEI-GISHym 22554, CSCS). B. M. fulvago Blank, Shinohara & Wei sp. nov. (5752, NSMT). C. M. gigantea Mocsáry, 1909, holotype of M. mikado Sato, 1930 (22350, NSMT). D. M. inversa Blank & D. R. Smith sp. nov., paratype (22356, USNM). E. M. langstoni Ross, 1936, holotype (30821, INHS). F. M. parki Shinohara, 1992 (18510, NSMT). G. M. pulchra Blank, Shinohara & Sundukov sp. nov., holotype (18501, NSMT). H. M. togashii Shinohara, 1992, holotype (22352, NSMT). Images not to the same scale.

Fig. 12. Species of Megaxyela Ashmead, 1898, ovipositors. A. M. euchroma Blank, Shinohara & Wei sp. nov., paratype, DEI-GISHym 22510 (NSMT). B – C. M. fulvago Blank, Shinohara & Wei sp. nov., paratype (5752, NSMT). C. Complete valvula 2 (incident light) and tip of valvula 2 (insert, transmitted light). D. M. inversa Blank & D. R. Smith sp. nov., paratype (22356, USNM). E. M. gigantea Mocsáry, 1909, holotype of M. mikado Sato, 1930 (22350, NSMT). F. M. parki Shinohara, 1992, paratype (18510, NSMT). G. M. pulchra Blank, Shinohara & Sundukov sp. nov., paratype (22348, NSMT). H. M. togashii Shinohara, 1992 (22353, NSMT). The images in B and H have been flipped horizontally.

Fig. 13. Species of Megaxyela Ashmead, 1898, penis valves (A – F) and genitalia capsules (G – I). A. M. euchroma Blank, Shinohara & Wei sp. nov. (DEI-GISHym 22513, NSMT). B. M. fulvago Blank, Shinohara & Wei sp. nov. (5239, NSMT). C. M. gigantea Mocsáry, 1909 (708, NSMT). D. M. parki Shinohara, 1992 (710, NSMT). E. M. pulchra Blank, Shinohara & Sundukov sp. nov. (18503, NSMT). F. M. togashii Shinohara, 1992 (22521, NSMT). G – H. M. gigantea, genitalia capsule in dorsal / ventral view (18507, NSMT). I. M. pulchra sp. nov., genitalia capsule in dorso-posterior view (22349, NSMT). Arrow heads in Fig. 13 H – I indicate lobe of upper side of valviceps coiled laterally. Images not to same scale.