Ostracod Research at the Lake Biwa Museum, Japan

Robin James Smith

Genus Cypretta Varva, 1895

Superfamily: Cypridoidea Baird, 1845
Family: Cyprididae Baird, 1845
Subfamily: Cyprettinae Hartmann, 1971

One species has been reported from Japan:

1. Cypretta seurati Gauthier, 1929

Dorsal views of two female Cypretta seurati, length 0.68 mm. This species is very globular. In this species, like most of the genus Cypretta, the right valve overlaps the left (a handful of species in the genus have the opposite overlap).

External view of a left valve of a female Cypretta seurati. Length 673 microns. The septa can be clearly seen along the anterior margin.

External view of a right valve of a female Cypretta seurati. Length 686 microns. The surface is covered in small, shallow pits (punctate).

Additional figures in: Okubo 1973; Okubo 2004; Smith & Kamiya 2006; Meisch et al. 2007; Smith et al. 2011.
Habitat: Rice fields, ponds (Okubo 1973), freshwater rockpools (Smith & Kamiya 2006), and Lake Biwa (Smith et al. 2011).
Mode of life: Nektobenthic (swimmer).
Reproduction mode: Asexual, males unknown.
Known distribution: Shiga, Okayama, Fukuoka, Miyazaki, Gunma, Kagoshima, and Shizuoka Prefectures (Okubo 1973; Okubo & Ida 1989; Smith & Kamiya 2006; Smith et al. 2011; Tanaka et al. 2015). Outside Japan widespread in lower latitudes (Meisch et al. 2007).

References:
⚬ Kim, W. & Min, G. S. 1991. Redescription of four recent freshwater ostracods (Crustacea: Ostracoda) from Korea. Korean Journal of Zoology, 34, 307-322.
⚬ Meisch, C., Mary-Sasal, N., Colin, J-P., & Wouters, K. 2007. Freshwater Ostracoda (Crustacea) collected from the islands of Futuna and Wallis, Pacific Ocean, with a checklist of the non-marine Ostracoda of the Pacific Islands. Bulletin de la Société des naturalistes luxembourgeois, 108, 89-103.
⚬ Okubo, I. 1973. Cypretta seurati Gauthier, 1929, from Japan (Ostracoda, Cyprididae). Proceedings of the Japanese Society of Systematic Zoology, 9, 1-6.
⚬ Smith, R. J., Janz, H. & Okubo, I. 2011. Recent Cyprididae and Ilyocyprididae (Crustacea: Ostracoda) from Lake Biwa, Japan, including a summary of the lake's ostracod fauna. Zootaxa, 2874, 1-37.
⚬ Smith, R. J. & Kamiya, T. 2006. Six new species of fresh and brackish water ostracods (Crustacea) from Yakushima, Southern Japan. Hydrobiologia, 559, 331-355.
⚬ 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.