Ostracod Research at the Lake Biwa Museum, Japan

Robin James Smith

Genus Metacypris Brady & Robertson, 1870

Superfamily: Cytheroidea Baird, 1850
Family: Limnocytheridae Klie, 1938
Subfamily: Timiriaseviinae Mandelstam, 1960

One species has been reported from Japan:

1. Metacypris digitiformis Smith & Hiruta, 2004

Dorsal view of a female Metacypris digitiformis, anterior to the bottom, length about 0.5 mm. Two large brood pouches, one in the posterior part of each valve, gives the female of this species a very distinctive heart shape in dorsal view.

External view of a female left valve of Metacypris digitiformis, length 491 microns.

External view of a female right valve of Metacypris digitiformis, length 481 microns.

Additional figures in: Smith & Hiruta 2004; Smith & Janz 2009; Sidorov & Semenchenko 2012.
Habitat: Littoral zones of a lake (Smith & Janz 2009); marshes (Smith & Hiruta 2004; Hiruta & Mawatari 2013); swampy ox-bow lake (Sidorov & Semenchenko 2012).
Mode of life: Benthic.
Reproductive mode: Sexual.
Known distribution: Shiga Prefecture (Smith & Janz 2009); Hokkaido (Smith & Hiruta 2004; Hiruta & Mawatari 2013). Elsewhere, far east of Russia (Sidorov & Semenchenko 2012).
References:
⚬ Hiruta, S. F. & Mawatari, S. F. 2013. Ostracods (Crustacea) from Sarobetsu Marsh, northern Hokkaido, Japan: taxonomy and phenology with description of Pseudocandona tenuirostris sp. nov. Species Diversity, 18, 57-74.
⚬ Sidorov, D. A. & Semenchenko, K. A. 2012. New records of freshwater ostracods (Crustacea) from the Far East of Russia, with a checklist of recent freshwater ostracods of the region. Arthropoda Selecta, 21, 227-234.
⚬ Smith, R. J. & Hiruta, S. 2004. A new species of Metacypris (Limnocytherinae, Cytheroidea, Ostracoda, Crustacea) from Hokkaido, Japan. Species Diversity, 9, 37-46.
⚬ Smith, R. J. & Janz, H. 2009. Recent ostracods of the superfamilies Cytheroidea and Darwinuloidea (Crustacea) from Lake Biwa, a Japanese ancient lake. Species Diversity, 14, 217-241.