Cyprinotus cf. kimberleyensis McKenzie, 1966

Ma, Shunxin & Yu, Na, 2020, Freshwater ostracods (Crustacea) from Hainan Island, southern China, with description of a new species, Zootaxa 4767 (2), pp. 201-243 : 222

Cyprinotus cf. kimberleyensis McKenzie, 1966

Figures 15–16 .

Material examined: Eight females, five males, three female valves and three male valves from QH4, two males ( ECNU 20170419/HN02 and ECNU 20171116/HN04) and one female ( ECNU 20171116/HN05) dissected; two females and two males from SY2, one male ( ECNU 20170414/HN03) dissected; 15 female carapaces and five male carapaces from SY1; ten females and five males from 11QH4.

Dimensions: Male, LV, n = 3, length 1.176 –1.227 mm, height 0.689 –0.814 mm; RV, n = 1, length 1.175 mm, height 0.706 mm; Female, LV, n = 1, length 1.283 mm, height 0.852 mm; RV, n = 1, length 1.246 mm, height 0.862 mm.

Description: Female. In lateral view, carapace sub-triangular. Greatest height situated at mid-length. RV overlapping LV with large dorsal hump; LV overlapping RV ventrally, anteriorly and posteriorly ( Fig. 15B ). Surface of carapace smooth. Marginal denticles present on RV along anterior, ventral and posterior margins ( Fig. 15A ). Marginal sockets along anterior, ventral and posterior margins of LV. Seta Sp on UR shorter than claw Gp. Claw Gp longer than half length of claw Ga ( Fig. 16A ). UR attachment simple.

Male. RV overlapping LV with dorsal hump, smaller than that of females ( Fig. 15D ). Posterior end wider than anterior. Right L5-endopod with thicker hook than left ( Fig. 16 B–C). Lateral shield of hemipenis well-developed. Ventral lobe of medial shield with a triangular end ( Fig. 16D ). Zenker organ with about 29 rows of spines ( Fig. 16E ).

Distribution: In this study, specimens were found in Sanya, Qionghai on Hainan Island.

Remarks: Compared with all reports of Cyprinotus species with hump ( Sars 1889, 1896; Brehm 1936; McKenzie 1966, 1978; Okubo 1974b, 2004; Victor & Fernando 1979a, b, 1981d; Battish 1981; Karanovic 2008), specimens found on Hainan Island are most similar to C. kimberleyensis , but the hump is slightly smaller than in McKenzie’s specimens, and so herein the species is referred to as C. cf. kimberleyensis . No males of C. kimberleyensis have been reported before ( McKenzie 1966; Okubo 1974b, 2004), but males of C. cf. kimberleyensis on Hainan Island demonstrate distinctive sexual dimorphism in the size and shape of the dorsal hump (see above).

Neale (1979) and Pinto & Purper (1980) both re-described the holotype of Cyprinotus cingalensis Brady, 1886 . Cyprinotus cingalensis is different from other Cyprinotus species in that it has two d setae on the basal segment of L6, the long setae on the terminal end of L7 (two long and one short setae) and the position of seta Sp on the UR, and it may not belong to the Cyprididae . Previous reports of C. cingalensis ( Victor & Fernando 1979b, 1981d; Sars 1889; Karanovic 2008) should be re-identified. There are seven species in the genus Cyprinotus now ( Martens et al. 2019). As Cyprinotus cingalensis is the type species of Cyprinotus and Cyprinotinae , the genus and the subfamily should be revised.

Figures

FIGURE 15. Cyprinotus cf. kimberleyensis McKenzie, 1966. A, ECNU20171116/HN05, female, internal view of RV; B, ECNU20170419/HN4-10, female, whole carapace, left lateral view; C, ECNU20170419/HN02, male, internal view of LV; D, ECNU20170419/HN4-9, male, whole carapace, left lateral view. Scale bars: 100 μm.

FIGURE 16. Cyprinotus cf. kimberleyensis McKenzie, 1966. A, ECNU20171116/HN04, male, UR; B, ECNU20170418/ HN02, male, right L5-endopod; C, ECNU20170418/HN02, male, left L5-endopod; D, ECNU20170418/HN02, male, Hp; E, ECNU20170418/HN02, male, Zenker organ. Scale bars: 100 μm.