2. Loxoconcha japonica Ishizaki, 1968 (Fig. 2)

Synonymy

Loxoconcha japonica sp. nov. ­ Ishizaki (1968): p. 28, Pl. 2, Fig. 1; Pl. 6, Figs. 10­12.

Loxoconcha japonica Ishizaki ­ Ishizaki (1971): p. 86, Pl. 3, Fig. 21; Okubo (1980): p. 416, Figs. 12, 13, 18a­d; Paik and Lee (1988): Pl. 3, Fig. 17; Tohru et al. (2005): Fig. 1A.

Material examined. One female dissected on slide (NIBR IV0000813441), shell of on micropalaeontology slide (NIBRIV 0000813441).

Locality in Korea. Gyeongsangnam­do, Goseong­gun, littoral, 34°59.629 ʹ N 128°26.201 ʹ E, 04/04/2012, coll. I. Karanovic.

Identifier. Ivana Karanovic.

Diagnosis (female only). Small ostracod, less than 1 mm long (Fig. 2A, B). Dorsal margin broadly rounded. Posterior margin rounded but with one clear caudal process terminated at 2/3 of height. Anterior margin rounded, and narrower than posterior one. Ventral margin straight to slightly concave. Valves not asymmetrical. Surface regularly reticulated. Marginal zone with long, straight canals. Hinge of Loxoconcha type (gongylodont). Antennula slender 6­segmented (Fig. 2C); all setae thin. Antenna 4­segmented with two distal claws (Fig. 2B).

Distribution. Species has been recorded throughout Japan. Paik and Lee (1988) also reported this species from Plio­Pleistocene deposits from Korea. Beside Okubo (1980) this is the second report of the species soft parts.

Remarks. The identification was based only on female specimens, because males have not been collected. Nevertheless, there are no significant differences between the original description and illustrations and our current record. This species belongs to the japonica species group (Tanaka and Ikeya, 2002).