Pseudocypretta lineata Ma & Yu 2020, n. sp.
Creators: name: Ma, Shunxin
name: Yu, Na
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Ostracoda
Podocopida
Cyprididae
Pseudocypretta
Pseudocypretta lineata

description: Pseudocypretta lineata n. sp.
Figures 6 A–G, 7 and 8.
Type locality: YND13: Yanuoda Rainforest Culture Tourist Zone, Sanya, Hainan Island, China, collected on 15 April, 2017 from a small pond, site information: 18.4583º N, 109.6450º E, elevation 252 m above sea level, water temperature 27.1 °C, salinity 0.04‰.
Additional locality: YND15: Yanuoda Rainforest Culture Tourist Zone, Sanya, Hainan Island, China, collected on 15 April, 2017 from a stream with leaf litter, site information: 18.4575º N, 108.6438º E, elevation 255 m above sea level, water temperature 28.0 °C, salinity 0.04‰.
Type material: Holotype: one female (ECNU20170415/HN48) from type locality dissected, valves stored dry in a micropalaeontological slide (ECNU20170415/HN48). Paratypes: five dissected females (ECNU 20170415/ HN37–39, 47, 49) from type locality, another 16 females from type and additional locality preserved in 70% ethanol.
Etymology: Derived from the Latin lineatus, referring to the longitudinal lines in the central-ventral area of the valves.
Dimensions: Female (holotype), width 0.377 mm. RV, length 0.431 mm, height 0.295 mm; LV, length 0.445 mm, height 0.307 mm. Others: n = 2, width 0.372 –0.382 mm; RV, n = 2, length 0.428 –0.437 mm, height 0.286 – 0.303 mm; LV, n = 2, length 0.438 –0.457 mm, height 0.297–389 mm.
Diagnosis: Carapace globular. LV overlapping RV ventrally. RV with septa both anteriorly and posteriorly (Fig. 6F). LV with short and poorly developed septa (Fig. 6G). Central-dorsal to central-ventral part of carapace surface pitted, grading to longitudinal lines in central-ventral area (Fig. 6B). Natatory setae on A2 long, exceeding tips of terminal claws. Claw G2 of A2 stout and strongly serrated (Fig. 7B). Gamma seta of Md palp smooth (Fig. 7C). L6 four-segmented, third segment undivided, e seta long, reaching to end of third segment (Fig. 8A). Terminal segment of L7 with short h2 seta, relatively slimmer h3 and stout h1 setae (Fig. 7E). UR reduced to triangular base with distal seta (Fig. 8B).
Description: Carapace globular with LV overlapping RV ventrally (Fig. 6E). In lateral view, dorsal margin strongly arched with maximum height at mid-length, anterior margin slightly more inflated than posterior margin, ventral margin slightly concave. In dorsal view egg-shaped, with maximum width posterior of mid-length, posterior margin more rounded than anterior margin, anteriorly with LV overlapping RV (Fig. 6A). Central-dorsal to centralventral part of carapace surface pitted, grading to longitudinal lines in central ventral area (Fig. 6B). Both valves with ventral outer lists, LV list extending to antero-dorsal area. LV calcified inner lamella wide in postero-ventral area and with list close to inner edge of inner lamella, grading to groove along ventral area and back to list on anterior calcified inner lamella (Fig. 6C). RV with inner list on postero-ventral area, and slight list in antero-ventral area (Fig. 6D). Septa present along RV anterior and postero-ventral margins (Fig. 6F). LV with short, weakly developed septa along anterior and postero-ventral margins, not reaching inner edge of calcified inner lamella (Fig. 6G).
A1 (Fig. 7A) seven-segmented. First segment with tiny Wouters organ, one dorsal and two long ventral setae. Second segment with tiny Rome organ and one dorso-apical seta. Third segment with one long dorso-apical seta and one short ventro-apical seta. Fourth segment with two long dorso-apical setae and two ventro-apical setae. Fifth segment with two ventro-apical setae and two dorso-apical setae. Sixth segment with four apical setae and one short alpha seta.Seventh segment with two long and one medium-length setae and one long aesthetasc ya.
A2 (Fig. 7B) four-segmented. Exopodite consisting of a small plate and three setae (two short and one long), long one exceeding end of next segment. Endopodite three-segmented. First endopodite segment with a aesthetasc Y, not reaching end of this segment. One seta present on the end of this segment, exceeding end of terminal segment. Natatory setae long, five setae exceeding tips of terminal claws, sixth seta approximately reaching end of third segment. Claws Gm and GM slim, claw Gm about 70% of length of claw GM. Claw G2 with strong serration, more robust than other claws. Seta z1 stout, setae z2 and z3 short. Seta t1 short, setae t2–t4 long.
Md palp (Fig. 7C) with four segments. First segment with slim, smooth alpha seta. Second segment with stout and hirsute beta seta. Third segment with smooth gamma seta.
Mx (Fig. 7D) endopodite two-segmented. First segment with group of four setae, and one sub-apical seta; second segment with three claws and two setae. Two tooth-bristles on third endite smooth. Terminal segment of palp cylindrical.
L6 (Fig. 8A) four-segmented. First segment with hirsute d1 seta. Second segment with long e seta, reaching to end of third segment. Third segment undivided, with long f seta at approximately mid-length, extending beyond end of third segment, and short g seta. Fourth segment with tiny h3 seta, longer h1 seta and stout h2 claw.
L7 (Fig. 7E) four-segmented. First segment with d1, d2 and dp setae. Second segment with short e seta. Third segment with f seta at approximately mid-length. Terminal segment with short h2, relative slimmer h3 and stout h1 setae.
UR (Fig. 8B) reduced. Basal part wide with one seta at mid-length.
Distribution: This species was found in a pool with submerged vegetation, and a stream with leaf litter in Yanuoda Rainforest Culture Tourist Zone, Sanya on Hainan Island.
Remarks: The subfamily assignment of the genus Pseudocypretta has been debated. It was considered similar to the genus Neozonocypris based on the four-segmented A2, the normally developed terminal segment of L7 (no pincer-organ) and the whip-like UR (Karanovic 2012). However, it was assigned to the subfamily Cyprettinae together with the genus Cypretta in the new checklist of non-marine Ostracoda (Meisch et al. 2019). On family level, this species could be assigned to Cyprididae rather than Notodromadidae, because there are only two tooth-like setae on the third endite of Mx (more than two in Notodromadidae). Although the genus Pseudocypretta is similar to Cyclocypridinae species in the absence of pincer organ at the end of L7 and the presence of natatory setae on A2, it differs, however, by the presence of septa along carapace margins, the two slightly long setae and one short seta on the terminal segment of L7 and the reduced UR (absence of septa along carapace margins, two short and one relatively long setae on the terminal end of L7 and the fully developed UR in Cyclocypridinae species) (Karanovic 2012). In all, we argue that this genus should better be assigned to the subfamily Cyprettinae because of the globose carapace, the presence of septa along carapace margins, the presence of the Rome organ and the long natatory setae of A2. Although the three setae on the terminal segment of L7 and the reduced UR are different from Cyprettinae species, a similar problem also exists in the genus Neocypridopsis (doubtable in Cypridopsinae, Meisch et al. 2019).
There are two genera in the subfamily Cyprettinae (Martens & Savatenalinton 2011; Meisch et al. 2019): Cypretta Vávra, 1895 and Pseudocypretta Klie, 1932. We assign our species to the genus Pseudocypretta in view of the terminal setae of L7 (Fig. 7E) and the reduced UR (Fig. 8B). Only Pseudocypretta maculata Klie, 1932 has been reported in this genus, found in Indonesia (Klie 1932), India (Battish 1982) and Thailand (Savatenalinton 2015), but it differs from the new species in the following characters: 1. the pits on the carapace do not grade into longitudinal lines in central-ventral area as in P. lineata n. sp. (Fig. 6B); 2. the two tooth-bristles on the third endite of Mx are serrated.
description: Published as part of Ma, Shunxin & Yu, Na, 2020, Freshwater ostracods (Crustacea) from Hainan Island, southern China, with description of a new species, pp. 201-243 in Zootaxa 4767 (2) on pages 212-215, DOI: 10.11646/zootaxa.4767.2.1, http://zenodo.org/record/3770727