Hydroptila oguranis Kobayashi, 1974

Ito, Tomiko, Ohkawa, Ayuko & Hattori, Toshio, 2011, The genus Hydroptila Dalman (Trichoptera, Hydroptilidae) in Japan, Zootaxa 2801, pp. 1-26 : 8-11

Hydroptila oguranis Kobayashi, 1974

( Figs. 5 , 14 C)

Hydroptila oguranis Kobayashi, 1974 , 68–69, pl. 25, male, Japan; Ito et al., 1998, figs 3–4, larva, case; Ito, 2005, 441, 446, fig. 21, male.

Hydroptila sp. Tanida et al., 1999, 394.

Adult. Wings dark brown with several small lighter markings. Antennae brown to light brown with darker markings at about half length and at apices.

Male. Lengths of forewing, hindwing and body 2.4–2.9 mm, 2.0– 2.5 mm and 3.0– 3.4 mm, respectively (n=5). Antennae 32–36-segmented; length 1.5–2.0 mm (n=5). Sternite VII ventral process small, apically subacute. Segment IX with large antero-lateral apodemes, postero-ventral margin with shallow concavity mesally and posterodorsal margin slightly produced and pointed mesally. Dorsal plate semi-membranous, in dorsal view subquadrate with shallow cleft on distal margin, rounded postero-lateral angles, in lateral view subtriangular and curved upward apically; internal sclerite subquadrate in dorsal view and dorsally curved and plate-like in lateral view. Subgenital plate composed of very wide triangular ventral plate and membranous lobe; ventral plate with 2 short setae ventrally. Phallic apparatus slender, with short hook-like subapical process, without titillator. Inferior appendages slightly shorter than dorsal plate, in ventral view triangular with apices directed postero-laterad, in lateral view gradually expanding distally, apex acute, forming small caudally directed process apically.

Female. Lengths of forewing, hindwing and body 2.8–3.4 mm, 2.2–2.8 mm and 3.1–3.7 mm, respectively (n=5). Antennae 26–27-segmented; length 0.9–1.2 mm (n=5). Abdomen increasingly darker from anterior to posterior; segment VII darkest and most hirsute. Ventral process of sternite VI small, apically subacute. Segment VIII in lateral view tergite slightly shorter than sternite, tergite and sternite fused laterally and weakly sclerotized; tergite rectangular with several marginal setae; sternite with median concavity on proximal margin, distal margin produced to form broad median lobe with 4 pairs of marginal setae. Bursa copulatrix thin, lozenge-shaped.

Immature stages. The final instar larva and case were described by Ito et al. (1998).

Specimens examined. Hokkaido: 32 males, 8 females, 7 larvae, Shibetsu-cho, Salmon Park, 6.VI– 22.VII.1996, TI & AO, S; 1 male, 61 females, Shibetsu-cho, Po-gawa, Pogawa-bashi, 22.VII–12.VIII.1996, TI et al., L & S; 2 females, Shibecha-cho, Kayanuma, Ikoinoie, 7.VIII.2006, TI, L; 1 male, 2 females, ibid., 25.VII.2008, TI, L; 2 males, Shibecha-cho, Kayanuma, Shirarutoro-etoro-gawa, Tomi-bashi, 25.VII.2008, TI, P; 3 males, 1 female, ibid., 16.VII–26.VIII.2009, TI, L; 2 males, 2 females, Shibecha-cho, Shirarutoro-ko, Togan, 25.VII.2008, TI, L; 6 males, 2 females, Kushiro-cho, Oboro-gawa, Oboro-bashi, 21.VI.1987, N. Kobayashi; 9 males, 57 females, Taiki-cho, Kimonto-gawa, Numakawa-hashi, 2.VIII.2007, TI, L; 5 males, 51 females, Eniwa-shi, Kashiwagi-gawa, Fukajo-bashi, 21.VI–12.IX.2000, TI & AO, L; 4 males, 26 females, ibid., 25–30.VI.2001, TI, L; 5 males, 2 females, Eniwa-shi, Kashiwagi-gawa, Kosoku, 25.VI.2000, TI, S; 5 males, 28 females, Eniwa-shi, Ichankoppe-zawa, 220 m, 19.VII.2010, TI, L; 1 male, 1 female, Eniwa-shi, Ichankoppe-zawa, 300 m, 10.VIII.2010, TI, L; 1 male, 2 females, Eniwa-shi, Moizari-gawa, Saiwai-bashi, 20.VII.2010, TI, L; 3 males, 6 females, Eniwa-shi, Megumino-chuo-koen, 13.VII.2003, TI & AO, S; 3 females, Chitose-shi, Chitose-gawa, Daiichi-usakumai-bashi, 18.VII.2001, TI & AO, L; 10 females, Chitose-shi, Bibi-gawa, Chitose-ko, 8.VII– 25.VIII.2001, TI & AO, L; 1 male, 5 females, ibid., 28.VII–20.VIII.2007, TI, L; 8 males, 21 females, Chitose-shi, Bibi-gawa, Bibi-bashi, 16.VIII.1993, TI, L; 11 males, 1 female, ibid., 29.VII.1998, TI, L; 94 males, 171 females, ibid., 25.VII–24.IX.1999, TI & AO, L & S; 4 males, 2 females, ibid., 15.VII.2001, TI & AO, L; 1 male, ibid., 8.IX.2002, TI, L; 2 males, 39 females, ibid., 4.VIII–6.IX.2007, TI, L; 17 males, 33 females, Tomakomai-shi, Dainibibi-bashi, 15.VII.2001, TI & AO, L; 57 males, 76 females, 3 larvae, Tomakomai-shi, Bibi-gawa, Matsubibi-bashi, VII–VIII.1990, TI, R; 1 male, 10 females, ibid., 9.IX.1990, TI, L; 3 males, 37 females, ibid., 18.VIII.1991, TI, L; 4 males, ibid., 29.VII.1998, TI & AO, S; 3 males, 13 females, ibid., 20.VIII.2007, AO, L; 123 males, 74 females, Tomakomai-shi, Bibi-gawa, Uenae-bashi, 9.VII–6.VIII.1977, TI, R & L; 50 males, 75 females, ibid., 24.VI.1978, TI, L; 132 males, 1904 females, ibid., 22–30.VII.2001, TI & AO, S & L; 114 males, 435 females, ibid., 3.VIII.2007, TI, L; 35 males, 301 females, ibid., 16.VIII.2008, TI, L; 313 males, 763 females, 8 pupae, 4 prepupae, Tomakomai-shi, Uenae, Bibi-gawa, 4 m, 8.VII–5.VIII.2010, TI, L; 2 males, Tomakomai-shi, Utonai-ko, Seigan, 28.VIII.1976, TI, S; 1 male, ibid., 6.VIII.1977, TH; 10 males, 37 females, ibid., 22.VII.2004, TI, L; 5 females, ibid., 17.VIII.2007, TI, L; 47 males, 37 females, Tomakomai-shi, Utonai-ko, near Yuburi-gawa-kako, 22.VII.2001, TI & AO, S; 1 female, Toyako-cho, Tsukiura, Toya-ko, 20.VI.2001, TI, S; 45 males, 30 females, Nanae-cho, Onuma, Choshiguchi, 31.V–23.VI.2003, TI & AO, S; 37 males, 87 females, ibid., 4.VIII.2006, TI & TH, L; 1 male, 4 females, ibid., 1.VII.2008, TI, L; 5 females, Nanae-cho, Onuma, Tsukimi-bashi, 31.V.2003, TI & AO, L; 59 females, ibid., 23.VI.2003, TI & AO, L; 2 females, Shiriuchi-cho, Idesu-gawa, Idesu-bashi, 6.VII.1998, AO, L. Honshu. Tokyo: 3 males, 5 females, Fussa-shi, Tama-gawa, Nagata-bashi, 23.VII.1993, TN. Kanagawa: 2 males, 4 females, Sagamihara-shi, Shiroyama-machi, Tanigahara, 21.IV.1984, TN; 10 males, 6 females, Yokosuka-shi, Ashina, 8.XI.2000, TN. Shizuoka: 1 male, Shizuoka-shi, Minami-abe, Suruga-ohashi, 2.VII.2005, TH, L; 130 males, 42 females, Shizuoka-shi, Ashikubo, Matsuzaki-bashi, 1.VI–21.XII.2005, TH, L; 11 females, Shimizu-cho, Kakida-gawa, 27.V.2001, TN & KT, L. Shiga: 3 males, 1 female, Otsu-shi, Shimo-sakamoto, Otsu Hydrobiological Station, 6.VIII.1987, K. Hiramatsu, L (LBM); 2 females, Hikone-shi, Iso, 9.IX.1986, N. Kobayashi, L (LBM); 1 female, Hikone-shi, Shiga-kenritsu-daigaku, 3–4.X.1998, AO; 12 males, 18 females, Takashima-shi, Imazu-hama, 2.VII.1986, N. Kobayashi, L (LBM); 7 males, 8 females, Omi-hachiman-shi, Maki, 8.IX.1986, M. Nishino (LBM); 1 male, ibid., 29.V.1987, KT, S (LBM); 1 female, Nishi-azai-cho, Oura-koen, 6.XI.1986, KT (LBM); 1 female, ibid., 3.VI.1988, KT, L (LBM); 11 females, Biwa-ko, Harie-hama, 24.V.1988, TN; 3 males, Koka-shi, Minakuchi, Nasaka, Imaike, Daichiji, 4.VII.2009, NKA, L (MKNM). Hyogo: 1 male, Shiso-shi, Yamasaki-cho, Michi-no-eki, 22.IX.1997, HN; 1 male, 1 female, Shiso-shi, Yamasaki-cho, Ibo-gawa, 8.VIII.2001, AO. Wakayama: 1 female, Kozagawa-cho, Hirai, 12–17.VII.1999, M. Maruyama. Shikoku. Tokushima: 1 male, Anan-shi, Naka-gawa, 11– 13.X.1998, S. Tsukaguchi. Kochi: 1 male, 1 female, Kami-shi, Tosa-yamada-cho, Sano, 5.X.2000, HN; 2 females, Motoyama-cho, Teraie, Yoshino-gawa, 250 m, 24.IX.2002, TH, L. Kyushu. Nagasaki, Tsushima Islands: 2 females, Tsushima-shi, Azamo, near esturary, 9.VII.2009, RBK, L (RBK). Kumamoto: 3 males, 11 females, Minami-aso-mura, Hakusui, Nakamatsu, AsoTanibito Museum, VII–IX.2002, AO; 1 male, Minami-aso-mura, Hakusui, Terasaka-suigen; 19.XI.2001, AO, S. Miyazaki: 1 female, Aya-cho, Yotsue, Honjo-gawa, 21.IV.2004, TH, L. Kagoshima, Amami Islands: 1 female, Tatsugo-cho, Toguchi-gawa, Kawato-bashi, 18.III.1999, TI & AO, L.

Remarks. The male of this species is similar to those of H. phenianica and H. thuna in having triangular inferior appendages and a somewhat quadrate dorsal plate, but it is clearly distinguished from the latter by the extremely short ventral plate of the subgenital plate, thick triangular inferior appendages, and a phallic apparatus bearing a very short subapical process. The female of this species is distinguishable from congeneric Japanese species by the weakly sclerotized tergite and sternite of abdominal segment VIII which are rectangular with slightly convex apical margins.

Distribution. Japan (Hokkaido, Honshu, Shikoku, Kyushu, Tsushima Islands, Amami Islands). Endemic to Japan.

Habitat. Adults were collected near lowland lakes, streams in marshes and artificial creeks.

Japanese name. Ogura-hime-tobikera.

Figures

FIGURE 14. Distributions of 12 species of Hydroptila in Japan and adjacent areas. For clarity, nearby collection sites in Japan are grouped together as a single point and the sites are roughly plotted in adjacent, non-Japanese areas.

FIGURES 5 – 6. 5, H. oguranis: A – C, male; A—abdominal segments VIII – X, lateral; B—genitalia, dorsal; C—same, ventral; D – F, female; D—abdominal segment VIII, lateral; E—abdominal segments VII – X, dorsal; F—same, ventral. 6, H. dampfi: A – C, male; A—abdominal segments VII – X, lateral; B—genitalia, dorsal; C—same, ventral; D – F, female; D—abdominal segments VII – X, ventro-lateral; E—same, dorsal; F—same, ventral.