Siobla hirasana Takeuchi, 1929

Shinohara, Akihiko, Wei, Meicai & Niu, Gengyun, 2013, Revision of Siobla (Hymenoptera, Tenthredinidae) from Japan, Zootaxa 3746 (1), pp. 1-40 : 12-14

Siobla hirasana Takeuchi, 1929

( Figs 1 e–f, 4a–c, 5e–f, 6c, 7c, 8c, l, 10d, 11e–h)

Siobla ferox var. hirasana Takeuchi, 1929: 497 .

Siobla ferox: Yano, 1932: 438 (in part); Esaki et al., 1939: 337 (in part); Takeuchi, 1952: 18 (in part); Togashi, 1965: 246 (in part), plate 123, 31; Naito, 1982: 574; Naito et al., 2004: 56 (in part); Yoshida, 2006: 92 (in part); Togashi, 2008: 490 (in part), plate 142, 2539.

Siobla hirasana: Malaise, 1945: 121 ; Taeger et al., 2010: 583; Niu & Wei, 2010: 49.

Siobla ferox forma hirasana: Takeuchi, 1950: 1348 .

“ Siobla ferox (F. Smith, 1874) ?”: Yoshida, 2006: 92 (in part).

Distribution. Japan (Honshu, Shikoku, Kyushu [new record]).

Primary type examined. Holotype of Siobla ferox var. hirasana ( Fig. 4a–c ): ♀, “ 22. VI. 1927, Mt. Hira, Takeuchi” “ Siobla ferox var. hirasana Takeuchi , Holotype ” (OPU). In the original description, the collection date of the holotype is noted “ June 22, 1928 ”, whereas the label data attached to the holotype is “ 22. VI. 1927 ”. We regard the difference as a lapsus.

Other material examined (see Appendix). 150 specimens (58 ♀ and 92 ♂).

Variation. The length varies from 12.5 to 16.0 mm in the female and 10.5 to 14.0 mm in the male. The colouration shows slight variation. In the female, the antenna is brown with the four or five apical antennomeres always black and two basal antennomeres often partly black. The posterior margin of the pronotum and the mesoscutellum (except for the outer margin) are always pale brown. The mesoscutellar appendage is always black. The metascutellum sometimes has a small brown mark medially. The hind trochanter and trochantellus are always pale brown. The fore and mid femora vary from almost entirely brown to almost entirely black. The abdominal tergum 1 is black, often with an obscure brown spot laterally, but never with a brown posterior margin. The males usually have more black areas on the antenna and the thorax than the females, though the basal flagellomeres always remain mostly or entirely pale brown. In a few very dark males, the pale marking on the mesoscutellum is missing and the tegula is mostly blackish.

Remarks. This species was originally described as a variety of S. ferox (Takeuchi, 1929) and has been mixed with it in collections. Siobla hirasana is a member of the S. ferox group defined by Niu & Wei (2010). The apically and often basally black and medially pale brown antenna of the female, the weakly convex mesoscutellum, the entirely black mesoscutellar appendage and metascutellum (sometimes with small pale mark) and the entirely or almost entirely black abdominal tergum 1 will separate S. hirasana from S. ferox .

The concept of S. ferox by Yano (1932), Esaki et al. (1939) and Takeuchi (1952) should include the present concept of S. hirasana . The female specimen shown by Togashi (1965) as S. ferox (31 in plate 123; also 2539 in plate 142 in Togashi, 2008) has basally and apically black antenna, a pale brown mesoscutellum, and an entirely black abdominal tergum 1. We were not able to locate Togashi’s specimen but it most probably belongs to S. hirasana . An examination of the specimens identified as S. ferox by Naito (1982) and Naito et al. (2004) has shown that at least part of them also belong to S. hirasana .

Figures

FIGURE 1. Siobla species, dorsal view. a. S. apicalis, ♀, Masutomi; b. S. apicalis, ♂, Amagi-toge; c. S. ferox, ♀, Mt. Kunimiyama; d. S. ferox, ♂, Mt. Kunimi-yama; e. S. hirasana, ♀, Ura-Myogi; f. S. hirasana, ♂, Hikagezawa; g. S. japonica, holotype, ♀; h. S. japonica, paratype, ♂, Marunuma. Scale bar = 1 mm.

FIGURE 4. a – c. Holotype of S. ferox var. hirasana. a. Labels; b. Dorsal view; c. Lateral view. d – f. Lectotype of S. jucunda. d. Labels; e. Dorsal view; f. Lateral view. g – i. Holotype of S. metallica. g. Labels; h. Dorsal view; i. Lateral view. j – l. S. sturmii (Lectotype of Macrophya pacifica). h. Labels; i. Dorsal view; j. Lateral view.