Stenocypris orientalis Victor & Fernando, 1981b

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 : 229-232

Stenocypris orientalis Victor & Fernando, 1981b

Figures 26–28 .

1981b Stenocypris orientalis n. sp. — Victor & Fernando: 158 –160, figs. 46–60.

Material examined: Three females from WN6, two females ( ECNU 20170417/HN19–20) dissected; one female from WN7, one female ( ECNU 20170417/HN21) dissected; three females and eight female valves from WZS4, two females ( ECNU 20170416/HN22–23) dissected.

Dimensions: Female, LV, n = 3, length 1.315 –1.462 mm, height 0.548 –0.621 mm; RV, n = 2, length 1.294 – 1.425 mm, height 0.542 –0.626 mm.

Description: Carapace elongated. LV overlapping RV anteriorly and posteriorly.Anterior margin more rounded than posterior ( Fig. 26A ). LV with inner groove along ventral and postero-ventral margins ( Fig. 26B ). Calcified inner lamella anteriorly and posteriorly wide. Septa narrow along free margins ( Fig. 26 C–D). Five long natatory setae on A2 not reaching to end of terminal claws. Sixth one reaching to mid-length of next segment. Claw G2 about three quarters of length of claw G1. Claw G1 slightly longer than claw G3. Claw Gm about half length of claw GM ( Fig. 27B ). One tooth-bristle on third endite of Mx smooth, and other with tiny setules ( Fig. 27D ). Terminal segment of L6 with one short h1 seta, long claw h2 and long h3 seta, about 1/3 length of claw h2 ( Fig. 28B ). Terminal stem of right UR with large, slightly grouped denticles ( Fig. 28D ). Terminal stem of left UR with four groups of denticles ( Fig. 28E ).

Distribution: This species has been found in the Philippines, Malaysia ( Victor & Fernando 1981b) and India ( Harshey & Thilak 2011). This species was found in Waning and Wuzhi Mountain on Hainan Island.

Remarks: The septa along the margins of the carapace in the Hainan Island species are shorter than those of S. orientalis found in the Philippines ( Victor & Fernando 1981b). The ratio of H and L of the valves is 0.39 in S. orientalis from the Philippines and Malaysia ( Victor & Fernando 1981b), 0.40 in Indian specimens ( Harshey & Thilak 2011) and 0.416 –0.439 in specimens from Hainan Island.

This species is similar to S. bolieki Ferguson, 1962 , having a long h3 seta on the L6. But the tooth-bristles on the third endite of Mx are toothed in S. bolieki , while one is smooth in S. orientalis . Additionally, the ratio between W and H is 0.34 in S. bolieki ( Rasouli & Aygen 2017) and 0.390 –0.439 in S. orientalis .

Figures

FIGURE 26. Stenocypris orientalis Victor & Fernando, 1981b. Female. ECNU20170417/HN19. A, external view of RV; B, internal view of LV; C, internal view of LV; D, internal view of RV. Scale bars: 100 μm.

FIGURE 27. Stenocypris orientalis Victor & Fernando, 1981b. Female. ECNU20170417/HN19. A, A1; B, A2; C, Md; D, Mx. Scale bars: 100 μm.

FIGURE 28. Stenocypris orientalis Victor & Fernando, 1981b. Female. A, ECNU20170417/HN21, L5; B, ECNU20170417/ HN19, L6; C, ECNU20170417/HN19, L7; D, ECNU20170417/HN19, right UR; E, ECNU20170417/HN21 left UR; F, ECNU20170417/HN20, UR attachment. Scale bars: 100 μm.