Xestoleberis marcula, Chand, Prerna & Kamiya, Takahiro, 2016

Chand, Prerna & Kamiya, Takahiro, 2016, Seven new species of the genus Xestoleberis (Ostracoda: Podocopida: Cytheroidea) from the Fiji Archipelago, Zootaxa 4208 (4), pp. 325-348 : 334-336

publication ID	https://doi.org/ 10.11646/zootaxa.4208.4.2
publication LSID	lsid:zoobank.org:pub:6D3B4F32-7196-4DF9-B6E5-401FCF4A4CE6
DOI	https://doi.org/10.5281/zenodo.6078105
persistent identifier	https://treatment.plazi.org/id/8B57EE20-FFFD-B306-B4CC-3E5C466D8BD7
treatment provided by	Plazi
scientific name	Xestoleberis marcula
status	sp. nov.

Treatment

Xestoleberis marcula n. sp.

Type series. Holotype: male UMUT RA32556 ( Figs. 6 View FIGURE 6 A–K, 2K–L). Paratypes: male: UMUT RA32560 ( Fig. 10 View FIGURE 10 C– D), females: UMUT RA32558 ( Fig. 6 View FIGURE 6 L), UMUT RA32559 ( Fig. 10 View FIGURE 10 A, E1–E5), UMUT RA32561 ( Fig. 10 View FIGURE 10 B). All type material was collected from the type locality. The holotype and paratypes are deposited at the University Museum , University of Tokyo, Japan . Valves on paleontological paper/cavity slides and soft parts mounted on glass slides. Additional paratypes preserved in 70% ethanol: two females UMUT RA32557.

Type locality. A rocky, open northwest coast of Tavewa Island in the Yasawa Group (P1, Fig. 1 View FIGURE 1 , Table 1); habitat: bluegreen alga.

Etymology. Marculus is Latin for hammer; the proximal structure of the hemipenes of this species is shaped like two hammers placed back-to-back.

Diagnosis. Carapace with widely rounded posterior and anterior ends. Anterior and ventral edges of valves lined with numerous simple marginal pores. Coloration in living specimens murky white with opaque patches. BO short segment with numerous fine terminating setae. Ejaculatory ducts have irregular arrangements with outward exists. Furca reduced to two short setae.

Description. Carapace reniform and strongly inflated ( Figs. 2 View FIGURE 2 G–H, 10F–K4). Maximum valve length range: 440 µm–465 µm, maximum valve height range: 260 µm–277 µm ( Table 2). Maximum height at mid-length. Dorsal margin convex, ventral margin slightly sinuous. Wide anterior and narrow posterior vestibula. Merodont hinge; median groove and bar of hinge finely locellate. Normal sieve pores scattered over carapace, normal simple pores lining anterior and antero-ventral edges of carapace. Scar pattern: posterior row of four adductor scars, single anterior scar V-shaped.

An1 with six podomeres; first two big, wide and rectangular, third–sixth small and quadrate ( Fig. 6 View FIGURE 6 A–A’). Third podomere with one dorsal apical seta, fourth and fifth podomeres with two dorsal apical seta, terminating setae of sixth podomere: one slender and round tipped, and three fine. An2 with one ventral seta on first podomere of endopodite, two smooth dorsal and two hirsute ventral medial setae and hirsute stout distal ventral apical seta on second endopodite podomere ( Fig. 6 View FIGURE 6 B–B’). No prominent serrations on terminating claws. Md coxa with two pointed and two lobate teeth and three fine setae ( Fig. 6 View FIGURE 6 C–E). Palp with four podomeres: medial ventral seta on first podomere, second podomere with one dorsal and two ventral apical setae, one medial seta at junction of second and third podomeres, third podomere with five dorsal and one ventral apical setae, fourth podomere with one stout and one fine terminating setae. Exopodite with at least two long setuled setae. Mx with two segmented palp; first segment with four distal dorsal-apical setae, second with three terminating setae ( Fig. 6 View FIGURE 6 F–F’). Branchial plate with 13 setuled setae. BO is symmetrical; short segment with numerous fine terminating setae ( Fig. 6 View FIGURE 6 G).

Basal setal formula for L5 1:2:1 and L6 and L7 1:1:1 ( Fig. 6 View FIGURE 6 H–J). Terminating claws L5, L6 and L7 short and curved. Hp with asymmetrical, trigonal and seta-like tipped distal processes; seta-like tip longer and more pronounced in one than other ( Fig. 6 View FIGURE 6 K). Proximal ends of capsules sub-rounded and proximal support structure shaped like two hammers placed back to back. Furca two short setae (one slightly shorter than other) on short base.

Distribution. Xestoleberis marcula n. sp. exhibits restricted distribution; specimens were only collected from one location (type locality above). Apart from the holotype habitat, specimens were also collected from green calcareous algae ( Halimeda opuntia and Halimeda incrassata ).

Remarks. The valve and Hp capsule shapes of X. marcula n. sp. are similar to Xestoleberis sesokoensis Sato & Kamiya, 2007 (Figs. 17–18, Sato & Kamiya 2007) from Okinawa, Japan. However, X. marcula n. sp. differs from X. sesokoensis with respect to the following: X. sesokoensis— A2 pectinate terminating claws, Mx dorsal apical setae of the palp are hirsute, Hp proximal support structure is curved downwards, Hp distal processes; one terminates into a fine seta while the other does not. X. marcula n. sp. —A2 claws with no prominent serrations, Hp proximal support structure hammer shaped, both distal processes of Hp terminate into a fine seta each.