Stactobia ineXpectata Botosaneanu & Nozaki 1996

Ito, Tomiko, 2017, The genus Stactobia McLachlan (Trichoptera, Hydroptilidae) in Japan, Zootaxa 4350 (2), pp. 201-233 : 213-215

Stactobia ineXpectata Botosaneanu & Nozaki 1996

( Figs 7 , 18 )

Stactobia inexpectata Botosaneanu & Nozaki 1996 , 55–56, holotype male, Honshu (Kanagawa, Yamanashi). Nozaki 1997, 33, 38, Honshu (Kanagawa); Kagaya et al. 1998, 43, 123, Honshu (Yamanashi); Nozaki 2004, 1234, Honshu (Kanagawa); Ito et al. 2010, 57, Hokkaido (Hiyama, Oshima); Moriya & Kubota 2012, 135, Honshu (Kanagawa); Kuhara & Ito 2017, 16, Yakushima.

Diagnosis. This species belongs to the S. martynovi Species Group and is distinguished from congeneric species by a long phallus spine, about ¾ length of phallus.

Description. Male ( Figs 7A–7G ). Antennae each 18-segmented and 0.9–1.0 mm long (n = 5). Length of each forewing and hind wing 2.0– 2.5 mm and 1.9–2.0 mm, respectively (n = 5). Tibial spur formula 1, 2, 4.

Genitalia. Tergite VII longitudinally shorter than sternite VII, sternite VII slightly expanded at anterior margin in lateral view, ventral process long with expanded spiny apex. Tergite VIII longitudinally shorter than sternite VIII. Tergite IX with pair of long anterior apodemes, sternite IX reduced. Tergite X semimembranous with pair of short, wide, oblique, sclerotized bands dorsolaterally. Subgenital appendages small with heavily sclerotized rounded apices mesally in ventral view. Inferior appendages small, heart-shaped with heavily sclerotized, rounded apices mesally in ventral view, subquadrate in lateral view. Phallus long, almost straight, slightly flattened with apex round; internal spine strongly sclerotized, long, about 20–25 times as long as basal width, almost straight but gently curved in few specimens, posterior part protruding from phallus in few specimens.

Final instar larva ( Figs 7H–7J ). Sclerites dark brown. Head about 0.23 mm wide, body up to 1.6 mm long. Thorax: setae on nota numbering about 30, 25, and 25, respectively; pair of short, transversely wide ventral sclerites in prosternum. Abdominal tergum I with single transverse mid-dorsal sclerite and pair of small round sclerites dorsolaterally. Other features typical of genus.

Case ( Figs 7K, 7L ). Length up to 1.8 mm. Anterior and posterior hoods large, distinctly convex laterally, each with smaller blunt apical projection and no incision. Other features typical of genus.

Specimens examined. HOKKAIDO. Ishikari: 3 males, Chitose-shi , Bifue-no-taki, 30.vii.2006, TI & TH. Shiribeshi : 1 male, Otaru-shi, Okusawa, Anataki, 12.vii.2001, AO; 8 males, Rankoshi-cho, Penke-mekunnaigawa, Momijino-taki, 25.vi.1997, TI & AO; 9 males, Rankoshi-cho, Niimi, small fall, 25.vi.1997, TI & AO. Oshima: 6 males, Mori-machi, Torisaki-keikoku, 4.vi.2009, TI. HONSHU. Iwate: 16 males, Oshu-shi, Koromogawa-ku, Keisho-san-taki, 19.vi.2017, TI . Miyagi: 6 males, Sendai-shi, Futakuchi, Natori-gawa, 400–500 m a.s.l., 8.vi.1974, TH . Niigata: 1 male, Kanose-machi, Koara, 13.vi.1998, M. Maruyama . Nagano : 8 males, Kisofukushima-cho, Field Station of Kyoto University, 31. v. 1993, NK . Shizuoka: 2 males, Shizuoka-shi, Hatanagi, Oigawa, small tributary, 700–750 m a.s.l., 7.viii.1994, TH ; 1 male, Shizuoka-shi, Hirano, 300–400 m a.s.l., 10.vii.1999, TH; 2 males, Shizuoka-shi, Umegashima, Minamisawa, 780 m a.s.l., 8.ix.2001, TH; 4 males, Shizuoka-shi, Umegashima, 1000 m a.s.l., 24.ix.2001, TH; 1 male, Shizuoka-shi, Hiyama, Nagato-gawa, 350 m a.s.l., 21.iv.2006, TH. Aichi: 1 male, Shinshiro-shi, Horai, Shimada-gawa, 11.vi.1996, HN ; 1 male, Shinshiro-shi, Horai, 14.vi.1997, HN. Mie: 4 males, Fujioka-shi, Mikunidani, 26.v.1996, HN . Hyogo: 1 male, Haga-cho, Hajirogawa, Fudo-no-taki, 8.viii.2001, AO ; 1 male, Asago-shi, Wadayama, Amago-taki, 5.iv.2009, K. Inazu. Nara: 6 males, Higashi-yoshino-mura, Takami-gawa, Izuo, 15.vi.1996, TN . Shimane: 1 male, Nagato-shi, Hibitaki-gawa, 6.viii.2001, AO ; 1 male, Hikimi-cho, Hikimi-kyo, 24.v.1993, NK. Okayama: 1 male, Tsuyama-shi, Okutsu-gawa, 5.v.2011, KN ; 5 males, Tsuyama-shi, Kagamino-cho, Koshiwata, 13.viii.2011, KN. Hiroshima: 3 males, Hatsukaichi-shi, Hosomi-dani, 11.v.2005, I. Mori. SHIKOKU . Tokushima: 34 males, Ichiu-mura, Kuwadaira, 900–1140 m a.s.l., 25.ix.2002, TH . Ehime: 10 males, Oda-cho, Odamiyama-keikoku, 880 m a.s.l., 20–22.iv.2000, TI & AO ; 1 male, same locality, 24.iv.2004, TH ; 7 males, Oda-cho, Odami-yama, Kurokawa, a tributary, 22.iv.2000, TI & AO; 1 male, Oda-cho, Koyayama, 29.v.2000, EY; 1 male, Omogo-mura, Teppoishi-gawa, 22.v.1999, TI & AO; 2 males, Omogo-mura, small fall on Skyline , 25.v.1999, TI & AO ; 1 male, Saijo-shi, Yosakoitoge, 22.v.2008, MT, & TI; 7 males, Uwajima-shi, Nametoko-keikoku, 400–600 m a.s.l., 23.ix.2002, TH. Kochi: 3 males, Higashi-tsuno-mura, Irazu-yama, headwater of Shimanto-gawa , 8.v.2004, MT ; 9 males, Monobe-son, Befukyo, small fall, 25.iv.2004, TH; 1 male, Monobe-son, Befu-kyo, 1300 m a.s.l., 13.viii.2004, K. Nio; 2 males, Hongawa-mura, Nano-kawa, Rokugo-bashi, 23.v.1999, TI & AO; 1 male, Hongawa-mura, Nano-kawa, 900 m a.s.l., 24.ix.2002, TH; 3 males, Hongawa-mura, Asatani, small fall, 24.ix.2002, TH; 1 male, Hongawa-mura, Terakawa, 5.vi.2004, MT; 3 males, Higashi-tsuno-mura, Irazu-yama, Shimanto-gawa, headwater, 8.v.2004, MT; 11 males, Higashi-tsuno-mura, Edaga-tani , 22.v.2004, MT ; 2 males, Kami-shi, Monobe, Shiraga-toge, small fall, 3.vii.2004, MT; 30 males, same locality, 22.v.2008, MT & TI ; 1 male, Kami-shi, Monobe, Nishikuma-keikoku, 25iv.2004, MT. KYUSHU. Oita: 3 males, Kusu-machi, Mori, Shimizu-bakuen, 450–500 m a.s.l., 18.ix.2002, TH ; 1 male, same locality, 18.iv.2004, TH . Miyazaki: 8 males, Tsuno-cho, Osuzu-yama, 750 m, a.s.l., 22.iv.2004, TH . Kagoshima: 3 males, Okuchi-shi, Kogihara, Jussa-gawa, 480 m a.s.l., 20–21.iv.2004, TH . Kagoshima, Yakushima : 5 males, detail data by Kuhara & Ito (2017); 7 final instar larvae, Miyanoura, Shiratani-gawa, 7 m a.s.l., 2.ix.1986, Y. Takemon.

Distribution ( Fig. 18 ). Hokkaido (Ishikari, Shiribeshi, Hiyama, Oshima); Honshu (Iwate, Miyagi, Niigata, Nagano, Yamanashi, Kanagawa, Shizuoka, Aichi, Mie, Hyogo, Nara, Shimane, Okayama, Hiroshima); Shikoku (Tokushima, Ehime, Kochi); Kyushu (Oita, Miyazak, Kagoshima, Yakushima). Newly recorded for Shikoku and Kyushu.

Habitat. Larvae of this species were collected by the above colleagues and me from waterfalls and very fast flowing streams.

Japanese name. Nagatoge-kaku-himetobikera.

Remarks. Final instar larvae and their cases are newly described.

Figures

FIGURE 7. Stactobia inexpectata Botosaneanu & Nozaki 1996. Male, final instar larva, and case. 7 A – 7 G, male: 7 A, abdominal segments VII – X, left lateral; 7 B, abdominal segments IX – X, dorsal; 7 C, same, ventral; 7 D, phallus, left lateral; 7 E – 7 G, same, variation. 7 H – 7 J, final instar larva: 7 H, right half of thorax, dorsal; 7 I, pro- and mesosterna, ventral; 7 J, abdominal segments I – III, dorsal. 7 K, 7 L, case: 7 K, dorsal; 7 L, ventral. Specimens: 7 A – 7 D = Hokkaido, Inakane-cho; 7 E = Ehime, Namakusa-dani; 7 F = Kochi, Higashi-tsuno-mura; 7 G = Mie, Fujiwara-cho; 7 H – 7 L = Yakushima, Nagata. Scale bars: 0.1 mm for 7 A; 1.0 mm for 7 K & 7 L.

FIGURE 18. Distributions in Japan of 6 species of Stactobia.