Dolerocypris ikeyai, Smith, Robin J., 2011

Smith, Robin J., 2011, Groundwater, spring and interstitial Ostracoda (Crustacea) from Shiga Prefecture, Japan, including descriptions of three new species and one new genus, Zootaxa 3140, pp. 15-37 : 20

Dolerocypris ikeyai Smith & Kamiya, 2006

( Figs 1 I–K, 3)

2006 Dolerocypris ikeyai n. sp. —Smith & Kamiya: 333–337, figs 2a–e, 4, 5, appendix.

Material examined. Within Shiga Prefecture: Two females from a spring runoff by the edge of a track in Hinocho, N35º 00’ 06.2”, E 136º 19’ 47.6”, 16 April 2008. 38 females from moss at a seep at the edge of a track in Hino-cho, N35º 00’ 10.0”, E136º 19’ 36.0”, 16 April 2008. Three females from a muddy seep at the edge of a track in Hino-cho, N35º 00’ 05.1”, E136º 19’ 35.5” 16 April 2008. 29 females from a seep at the edge of a track in Hinocho, N35º 00’ 02.1”, E136º 19’ 32.2”, 16 April 2008. Four females from a hole dug into the riverbank of a tributary of the Yasu River, Tsuchiyama-cho, Koka, N35º 00’ 18.1”, E136º 22’ 26.7”, 29 January 2010. 24 females from a spring fed stream in Ueno, Maibara, N35º 23’ 24.39”, E136º 23’ 21.66”, 2 August 2010 (collected by Francesc Mezquita). Outside Shiga Prefecture: 66 females and 40 males from the runoff of a small spring at the beach of Nishinoomote, Tanegashima Island, Kagoshima Prefecture, N30º 47’ 27.6”, E131º 04’ 52.1”, 22 March 2003. 120 females from a small seep and its runoff near Futatsuga Ike, Hiroshima-shi, Hiroshima Prefecture, N34º 23’ 04.5”, E132º 32’ 10.7”, 5 August 2004. Three females from a small seep by the Miso River, Mikumari Park, Hiroshima, Hiroshima Prefecture, N34º 24’ 26.1”, E132º 31’ 30.6”, 7 August 2004. 19 females from a small, slowly flowing stream in Kanazawa, Ishikawa Prefecture, N36º 34’ 18.4”, E136º 42’ 29.7”, 23 July 2004. 19 females from below a small waterfall by the road in Takao, Kanazawa, Ishikawa Prefecture, N36º 30’ 15.2”, E136º 38’ 53.4”, 30 June 2004. Five females from a boggy area by side of the road in Takao, Kanazawa, Ishikawa Prefecture, N36º 30’ 19.0”, E136º 38’ 53.1”, 30 June 2004. 32 females from a small spring in a coastal cliff face, near Kodomari, Tsugaru Peninsula, Aomori Prefecture, N41º 07’ 09.9”, E140º 17’ 09.7”, 24 September 2004. Nine females from a small trickle along a gravel track near Tairadate, Tsugaru Peninsula, Aomori Prefecture, N41º 08’ 55.2”, E140º 37’ 43.9”, 25 September 2004. 226 females from the runoff of a small spring at Yatsuse Bridge, Chichijima Island, Ogasawara, N27º 03’ 16.8”, E142º 11’ 58.1”, 1 June 2004. Material collected by the author unless stated otherwise.

Intraspecific variation. Colour of carapace varies from green through to pale green/blue to white. CR variable, with some specimens with more robust and proportionally shorter ramus and claws. Sp either slender, short seta, or shorter, stubbier, more spine-like form ( Fig. 3 ).

Remarks. This species was first described from Yakushima Island, southern Japan (Smith & Kamiya 2006), but the author has also found it in groundwater runoffs from Kagoshima (Tanegashima Island), Hiroshima, Ishikawa, Aomori and Shiga Prefectures, and the remote Ogasawara Islands (see material examined section for details). The Ogasawara Islands are approximately 1000 km south of the main island of Honshu and have never been connected to another landmass during their history. This may indicate that this species has high dispersal potential and hence may be found in other places other than Japan if suitable habitats are examined. Sexual populations have only so far been found on Tanegashima and Yakushima Islands, suggesting that this species is geographically parthenogenetic. It prefers groundwater runoff, often found in very shallow (<20 mm), slowly flowing water a short distance downstream from small springs or seeps, on a muddy substrate.

Figures

FIGURE 3. Caudal rami of Dolerocypris ikeyai. Inserts detail of Sp setae. A. (LBM 1430005074). B. (LBM 1430005073).

FIGURE 1. A – H, Cavernocypris cavernosa n. sp. A. dorsal view of whole carapace, anterior to right (LBM 1430005066). B. right lateral view of whole carapace (LBM 1430005066). C. internal view of right valve (LBM 1430005069). D. nternal view of left valve (LBM 1430005068). E – oblique internal view of left valve, ventral margin uppermost (LBM 1430005068). F. oblique internal view of right valve, ventral margin uppermost (LBM 1430005069). G. ventral view of left valve (LBM 1430005067). H. ventral view of right valve (LBM 1430005070). I – K, Dolerocypris ikeyai. I. left lateral view of carapace (LBM 1430005071). J. external view of left valve (LBM 1430005072). K. internal view of left valve (LBM 1430005073). L & M, Eucypris pigra. L. right lateral view of whole carapace (LBM 1430005075). M. dorsal view of whole carapace, anterior to right (LBM 1430005076). Scale bar = 319 µm for A – H, 609 µm for I – K, and 535 µm for L & M.