Setodes chirotheca Katsuma 2018, sp. nov.

Setodes chirotheca sp. nov.

(Figs. 1A–1G, 10A)

Setodes minutus: Katsuma 2006, 36, Honshu (Ibaraki). Misidentification mentioned by Katsuma (2008).

Setodes sp.: Katsuma 2007, 18, Honshu (Tochigi); Katsuma 2011, 68, Honshu (Ibaraki); Tanaka 2012, 10, male, Honshu (Akita); Ito 2013, 70, Hokkaido (Kushiro); Katsuma 2015, 91, Honshu (Ibaraki).

Diagnosis. The male of this species is similar to those of S. moritai sp. nov. and S. obscurus Schmid & Levanidova 1986 described from Far East Russia. The shape of the paramere spines and inferior appendages in lateral view distinguish the male of S. chirotheca from those of the latter species. Each of these paramere spines is curved downward near the tip without any subapical spine. In S. moritai, each spine is curved upward and then bent caudad about 1/6 distance from the tip, and in S. obscurus each spine is curved upward near the tip. In lateral view, the upper lobe of each inferior appendage is strongly extending dorsocaudad in S. chirotheca, but weakly extending dorsocaudad in S. moritai and S. obscurus. The female of this species is similar to that of S. moritai, but they are distinguishable from each other by the shape of the genital chamber in ventral view: The anteroventral margin is shallowly concave in S. chirotheca but deeply concave in S. moritai.

Adult. Head and body pale yellow. Forewings each 5.2–6.5 mm long (n = 15) in male, 6.7–7.7 mm (n = 17) in female, covered by golden hair with many silver spots. Wing venation typical for genus.

Male genitalia. Segment IX longitudinally short dorsally, long ventrally with many strong setae. Segment X fused with tergum IX, triangular in lateral view, with pair of sclerotized spine-like processes apically; but tips of segment X and apical processes variable in shape: In lateral view, each tip of segment X long-triangular with tiny spine apicoventrally (Fig. 1 Ba), triangular with bifid apex (Fig. 1 Bb), triangular with tiny spine apically (Fig. 1 Bc), triangular without tiny spine (Fig. 1 Bd), or semi-trapezoidal without tiny spine (Fig. 1 Be). Preanal appendages vestigial, integrated into segment X, appearing as pair of oval setose mounds. Inferior appendages mitten-like in lateral view; each upper lobe triangular in lateral view, acute at apex, with short triangular process basomesally; each lower lobe broad, round apically in lateral view with many setae. Phallic shield triangular in lateral view; phallobase syringe-like in lateral view. Phallicata broad, bow-like in lateral view, evenly bent downward midway. Paramere spines paired, arising from endotheca, extending caudad, curved downward near tips.

Female genitalia. Segment IX longitudinally long dorsally, short ventrally with many strong setae. Segment X rectangular in lateral and dorsal views, with pair of longitudinal carinae dorsally. Preanal appendages fused with tergum IX, with many short setae. Lamellae capitate in lateral view, narrowest at base, broadest about apical 1/4, each with small mesal lobe bearing 6–7 short hooked setae posteromesally. Gonopod plate fused with sternum IX, with pair of sclerotized longitudinal flanges ventrolaterally, crown-shaped in ventral view. Spermathecal sclerite semi-oval in ventral view, with long acute process posteriorly. Genital chamber triangular in ventral view, large and well sclerotized, extending into segment VIII; anteroventral margin shallowly concave in ventral view.

Immature stages. Unknown.

Etymology. Latin feminine noun in apposition, “chiro-“ and “-theca”, literally “hand sheath”, broadly translated “mitten” or “glove,” with reference to the shape of the inferior appendages in lateral view.

Distribution. Japan (Hokkaido, Honshu (north to central)).

Japanese name. Higashi-seto-tobikera.

Holotype. ♂ (in alcohol), Ibeshibetsu-gawa, Akan-cho, Kushiro-shi, Hokkaido, Japan, 43°28’N, 144°7’E, 11.viii.1996, T. Ito leg. (CBM-ZI 166027).

Paratypes. 2♂ 11♀ (in alcohol) same data as the holotype (CBM-ZI 166028–166040).

Other Specimens examined. Hokkaido: 1♂ 1♀, Sarufutsu-gawa, Sarufutsu-mura, Soya, 31.vii.2007, T. Ito; 1♂, Shumarinai, Horokanai-cho, Kamikawa, 2.viii.2017, T. Ito; 2♀, Ibeshibetsu-gawa, Akan-cho, Kushiro-shi, 31.viii.1996, T. Ito; 3♂ 22♀, ibid, 26.vii.1999, T. Ito; 4♂ 15♀, ibid, 27.vii.1999, T. Ito & A. Ohkawa; 2♂, ibid, 13.ix.1999, T. Ito & N. Minakawa; 1♂ 4♀, ibid, 9.viii.2007, T. Ito; 1♂, Akan-ko, Akan-cho, Kushiro-shi, 31.viii.2002, T. Ito; 6♂ 7♀, ibid, 7.viii.2007, T. Ito; 1♂, Takkobu-numa, takkobu, Kushiro-cho, Kushiro, 8.viii.2006, T. Ito; 9♂ 21♀, Otofuke-gawa, Shihoro-cho, Tokachi, 28.vii.2008, T. Ito; 5♂ 79♀, ibid, 12.viii.2008, T. Ito; 1♂ 3♀, Chitose-gawa, Daiichi-usakumaibashi, Chitose-shi, 5.viii.2007, T. Ito; 1♂, Chitose-gawa, Rankoshi, Chitose-shi, 12.ix.1999, T. Ito; 1♂, ibid, 18.vii.2001, T. Ito & A. Ohkawa; 1♂, Chitose-ko, Bibi, Chitose-shi, 3.ix.2001, T. Ito; 13♂ 37♀, Uzura-gawa, Kozuki-bashi, Assabu-cho, Hiyama, 3.viii.2006, T. Ito & T. Hattori. Aomori: 1♂, Kabahagi-sawa, Aomori-shi, 2.vii.2011, Y. Murakami; 2♂ 3♀, Tsukimino, Aomori-shi, 9.vii.2011, Y. Murakami. Iwate: 1♀, Yakushi-gawa, Taimagura, Etsunagi, Miyako-shi, 10.viii.1994, T. Hattori. Akita: 1♀, Sannaimitsumata, Yokote-shi, 5.viii.2011, M. Tanaka; 1♀, ibid, 8.viii.2011, M. Tanaka. Miyagi: 1♂ 1♀, Natorigawa, Akiu-machi, Taihaku-ku, Sendai-shi, 25.vi.2011, N. Katsuma. Fukushima: 2♂ 1♀, Surikami-gawa, Nakamoniwa, Iizaka-machi, Fukushima-shi, 31.vii.1996, T. Kishimoto; 1♂ 33♀, Yanohara-kogen, Showa-mura, 19.viii.2008, N. Katsuma; 4♀, Shitoki-gawa, Shitoki-ohashi, Miyamae, Kawabe-machi, Iwaki-shi, 11.vii.2010, N. Katsuma; 28♂ 6♀, Shitoki-gawa, Oinudaira, Tabiuto, Tabito-machi, Iwaki-shi, 15.viii.2009, N. Katsuma. Tochigi: 1♀, Akiyamagakuryo, Akiyama-cho, Sano-shi, 23.viii.2014, K. Tojo; 1♀, Naka-gawa, Ogawa, Nakagawa-machi, 6.viii.2005, N. Katsuma. Ibaraki: 1♂, Okami, Hitachiota-shi, 8.viii.2009, N. Katsuma; 1♂, Takinokura-shitsugen, Kamikimida, Takahagi-shi, 18.viii.2010, N. Katsuma; 1♂, Ai-kawa, Shimoisehata, Hitachiomiya-shi, 18.vi.2005, N. Katsuma. Tokyo: 1♀, Minamiaki-gawa, alt. 740m, Kazuma-kami, Hinohara-mura, 23.vi. 2010, T. Nozaki & T. Kagaya.

Remarks. Setodes chirotheca sp. nov., S. moritai sp. nov., and S. obscurus belong to the Primitive Branch (Schmid 1987) since the morphological characteristics of male genitalia are consistent with the theoretical ancestor of Setodes: 1) male genitalia are essentially simple and basically little specialized; 2) segment X is thick, roofshaped, and extending backward; 3) inferior appendages are more or less branched; and 4) the phallic apparatus is complete with phallobase, endotheca, phallicata, and paramere spines. Schmid & Levanidova (1986) placed S. obscurus among ‘‘isolated species’’ in this Branch.