Ostracod Research at the Lake Biwa Museum, Japan

Robin James Smith

Genus Tanycypris Triebel, 1959

Superfamily: Cypridoidea Baird, 1845
Family: Cyprididae Baird, 1845
Subfamily: Cypricercinae McKenzie, 1971

Two species have been reported from Korea:

1. Tanycypris alfonsi Nagler, Geist & Matzke-Karasz, 2014

Left side view of a female Tanycypris alfonsi, length 1.3 mm.

Dorsal view of a female Tanycypris alfonsi, anterior to left, length 1.3 mm.

External view of a female left valve of Tanycypris alfonsi, length 1253 microns.

External view of a female right valve of Tanycypris alfonsi, length 1242 microns.

Additional figures in: Okubo 1972 (as Strandesia camaguinensis); Okubo & Ida 1989 (as Tanycypris pellucida); Okubo 2004 (as Tanycypris pellucida); Nagler et al. 2014; Smith et al. 2014.
Habitat: Irrigation ponds (Smith et al. 2014). Elsewhere, rice fields, shallow ponds (Okubo 1972), and artificial containers in greenhouses (Nagler et al. 2014).
Mode of life: Nektobenthic (swimmer).
Reproductive mode: Asexual.
Known distribution: Jeju Island (Smith et al. 2014). Elsewhere, known from Japan (Okubo 1972; Okubo & Ida 1989; Okubo 2004), and Germany, where it is considered to be an alien species (Nagler et al. 2014).
Remarks: See below for T. centa.
References:
⚬ Chang, C. Y., Lee, J. & Smith, R. J. 2012. Nonmarine ostracods (Crustacea) from South Korea, including a description of a new species of Tanycypris Triebel (Cyprididae, Cypricercinae). Zootaxa, 3161, 1-19.
⚬ Matzke-Karasz, R., Nagler, C. & Hofmann, S. 2014. The ostracod springtail - camera recordings of a previously undescribed high-speed escape jump in the genus Tanycypris (Ostracoda, Cypridoidea). Crustaceana, 87, 1072-1094.
⚬ Nagler, C., Geist, J. & Matzke-Karasz, R. 2014. Revision of the genus Tanycypris (Ostracoda, Cypricercinae) with the description of Tanycypris alfonsi n. sp., and an identification key to the genus. Zootaxa, 3821, 401-424.
⚬ Okubo, I. 1972. Strandesia camaguinensis Tressler, 1937, from Japan (Ostracoda, Cyprididae). Proceedings of the Japanese Society of Systematic Zoology, 8, 9-14.
⚬ Okubo, I. 2004. Nihon tansui san kaimijinko rui ni tsuite. Kabushikigaisha Sanmon Insatsusho, Okayama, Japan, 72pp. [In Japanese, privately published].
⚬ Okubo, I. & Ida, K. 1989. Freshwater Ostracoda from Gunma Prefecture, Japan (In Japanese). Bulletin of the Biogeographical Society of Japan, 44, 105-107.
⚬ Smith, R. J., Lee, J. & Chang, C. Y. 2014. Nonmarine Ostracoda (Crustacea) from Jeju Island, South Korea, including descriptions of two new species. Journal of Natural History, http://dx.doi.org/10.1080/00222933.2014.946110, 1-40.

2. Tanycypris centa Chang, Lee & Smith, 2014

Left side view of a female Tanycypris centa, length 1.1 mm.

External view of a female left valve of Tanycypris centa, length 1153 microns.

External view of a female right valve of Tanycypris centa, length 1133 microns.

Additional figures in: Chang et al. 2014.
Habitat: Lower reaches of river (Chang et al. 2012), irrigations pond (Smith et al. 2014), and artificial containers in greenhouses (Nagler et al. 2014).
Mode of life: Nektobenthic (swimmer).
Reproductive mode: Asexual.
Known distribution: Hyeongsan River, North Gyeongsang Province (Chang et al. 2012), Jeju Island (Smith et al. 2014). Elsewhere, Germany and Japan, where it is considered to be an alien species (Nagler et al. 2014; Smith et al. 2024).
Remarks: Both this species and T. alfonsi have been observed jumping from a substrate, using their extremely long and powerful caudal rami. This is probably an escape mechanism from predators (Matzke-Karasz et al. 2014).
References:
⚬ Chang, C. Y., Lee, J. & Smith, R. J. 2012. Nonmarine ostracods (Crustacea) from South Korea, including a description of a new species of Tanycypris Triebel (Cyprididae, Cypricercinae). Zootaxa, 3161, 1-19.
⚬ Matzke-Karasz, R., Nagler, C. & Hofmann, S. 2014. The ostracod springtail - camera recordings of a previously undescribed high-speed escape jump in the genus Tanycypris (Ostracoda, Cypridoidea). Crustaceana, 87, 1072-1094.
⚬ Nagler, C., Geist, J. & Matzke-Karasz, R. 2014. Revision of the genus Tanycypris (Ostracoda, Cypricercinae) with the description of Tanycypris alfonsi n. sp., and an identification key to the genus. Zootaxa, 3821, 401-424.
⚬ Smith, R. J., Lee, J. & Chang, C. Y. 2014. Nonmarine Ostracoda (Crustacea) from Jeju Island, South Korea, including descriptions of two new species. Journal of Natural History, http://dx.doi.org/10.1080/00222933.2014.946110, 1-40.
⚬ Smith, R. J., Ozawa, H., Nishida, S. & Nakai, S. 2024. Non-marine Ostracoda (Crustacea) collected from pet shops and a hobbyist's aquaria in Japan, including two new species. Zootaxa 5410 (4), 451–494.