Pseudocandona abei Smith and Janz, 2008

Ma, Shunxin & Yu, Na, 2018, Freshwater ostracods (Crustacea) from Tiantong National Forest Park and Dongqian Lake, eastern China, with descriptions of two new species, Journal of Natural History 52 (27 - 28), pp. 1825-1868 : 1832-1835

Pseudocandona abei Smith and Janz, 2008

( Figures 4d–f , 6 )

Pseudocandona abei sp. nov. Smith and Janz, 2008: 2909–2912, figs. 26A,B, 27 and 28.

Material examined

Two females (ECNU20140909/TT80, 81) dissected.

Dimensions

(Female, n = 3) Length, 0.64–0.67 mm; height, 0.35–0.38 mm.

Brief description

Female, carapace bean-shaped in lateral view; dorsal margin arched; maximum height at middle; LV overlap RV along all free margins; carapace smooth; long setae present along both anterior and posterior margins. A1 seven-segmented; first segment with two setae dorsally and ventrally, respectively; second and third segments with one seta each. A2 four-segmented; first endopodal segment with two setae ventro-distally, long one reaching to end of terminal segment, short one reaching to end of next segment; claw G2 short, not reaching to middle of claws G1 and G3; claw G3 slightly shorter than claw G1; claw Gm slightly exceeding middle of claw GM. Md with coxa and four-segmented palp. Second segment of palp with 3 + 2 setae group ventrally. Two bristles on the third masticatory lobe of Mx1 palp smooth. L5 with one a, one b and one d setae, all long. L6 five-segmented; basal segment with one hirsute d1 seta; two g setae present on the end of penultimate segment, one long and hirsute, exceeding end of terminal segment, and one short and smooth, reaching to end of terminal segment. L7 four-segmented; basal segment with three d setae; seta dp twice as long as seta d1; setae e and f missing; seta g long; terminal segment with two long and one short setae; seta h1 equalling 2.5 times as long as length of terminal segment. UR with two claws and two setae; claw Gp slightly shorter than claw Ga; both claws serrated; seta Sa small; seta Sp long, exceeding terminal end of stem. UR attachment with two branches distally.

Distribution

This species has been reported from Japan ( Smith and Janz 2008) and it is a new report for China.

Remarks

This species is morphologically similar to Pseudocandona geratsi Broodbakker from Venezuela, and the differences between the two species have been discussed by Smith and Janz (2008). Differences include the maximum height of the carapace (located at mid-length in P. abei and posterior of mid-length in P. geratsi ), and the length of the h1 seta of the L7 (half the length of the h2 seta in P. abei and shorter than half the length of the h2 seta in P. geratsi ). The dorsal end of the UR attachment has a broad, angular lobe in the Chinese specimens, whereas there are two short branches in Japanese specimens. Japanese specimens of P. abei were investigated for this study by the original author, which revealed that there is one dorsal seta present on the third segment of the A1 (missing in the original description).

Figures

Figure 4. (a–c) Fabaeformiscandona subacuta (Yang, 1982, in Hou et al., 1982). (a) ECNU20140907/ TT23, external view of RV (Female); (b) ECNU20140907/TT23, internal view of RV (Female); (c) ECNU20140907/TT24, external view of LV (Male). (d–f) Pseudocandona abei Smith and Janz, 2008. Female. (d) ECNU20140909/TT80, external view of LV; (e) ECNU20140909/TT80, internal view of RV; (f) ECNU20140909/TT8001, dorsal view. Scale bars: 100 μm.

Figure 6. Pseudocandona abei Smith and Janz, 2008. (a, c and e) (ECNU20140909/TT81); (b, d, f–i) (ECNU20140909/TT80). Female. (a) A1; (b) A2; (c) Md palp; (d) L5; (e) Md coxa; (f) L6; (g) L7; (h) UR attachment; (i) UR. Scale bars: 100 μm.