3. Loxoconcha tosaensis Ishizaki, 1968 (Figs. 3-5)
Synonymy
Loxoconcha tosaensis sp. nov. Ishizaki (1968): p. 31, Pl. 2, Fig. 3; Pl. 7, Figs. 6 9.
Loxoconcha tosaensis Ishizaki Ishizaki (1971): p. 87, Pl. 3, Fig. 18; Tohru et al. (2005): Fig. 1G; Yasuhara and Seto (2006): Fig. 4m.
Material examined. One male dissected on slide (NIBR IV0000813449), shell of on micropalaeontology slide (NIBRIV 0000813449).
Locality in Korea. Jeollanamdo, Goheunggun, littoral close to Naro Space Center, 34°27.348 ʹ N 127°31.216 ʹ E, 18/08/2013, coll. I. Karanovic.
Identifier. Ivana Karanovic.
Diagnosis (male only). Small ostracod, less than 1 mm long (Fig. 3A, B). In lateral view, carapace oblong, slightly depressed anterodorsally. Dorsal margin straight. Ventral margin straight to slightly convex around mouth region. Anterior margin broadly rounded. Posterior margin closes down on dorsal margin with angle; but no prominent caudal process. Surface ornamented with relatively regular coarse reticulation throughout. Eye tubercle distinct. Hinge of Loxoconcha type (gongylodont). Antennula 5segmented with slender segments. Antenna 4segmented: first segment carrying only spinneret seta (exopod), second segment with one posterodistally reaching middle of the following segment. Penulitmate segment with two setae situated anteriorly on one third of segment’s length, and three setae posteromedially, slightly below external setae, penultimate segment also carrying two short setae posterodistally; terminal segment with two claws (Fig. 5B). Mandibula (Fig. 4A) with two claws and two setae on terminal segment. Mandibular exopod with three setae. Vibratory plate of maxillula with 15 rays; maxillular palp 2-segmented, first segment carrying three setae; terminal segment elongated and with four setae. All maxillular endites with four setae, and third one in addition with one very thick seta situated proximally. Hemipenis (Fig. 5A) with triangular distal part and one additional lateral projection being very similar in shape like distal part; clasping organ withheld internally and in rodlike shape.
Distribution. Species has been reported from Japan, and it was known only from its shell. This is the first report of soft parts.
Remarks. This is the first description of the soft parts of L. tosaensis . It belongs to the uranouchiensis species group (Tanaka and Ikeya, 2002).