Coeloperix sinica, Pan & Jiang & Fan & Al-Farraj & Gao, 2017

COELOPERIX SINICA SP. NOV. ( FIG. 2; TABLE 2)

Diagnosis: Marine Coeloperix with an oval body shape, with a size of about 50–60 × 20–40 µm in vivo; four preoral and 15 postoral kineties, the latter of which comprising ten right kineties and five left kineties; cross-striated band (CSB) interrupted at posterior 1/4 of right margin; 14 or 15 nematodesmal rods; usually three finger-like tentacles on ventral side; macronucleus ellipsoidal; two contractile vacuoles diagonally located.

Type materials: A protargol slide with the holotype was deposited in the Natural History Museum, London, with the registration number NHMUK 2016.3 About NHMUK .21.1. Another protargol slide with paratypes was deposited in Laboratory of Protozoa , Ocean University of China with the registration number FXP08060904-02. Relevant specimens are marked by black ink circles on the coverslip .

Type locality: A sand beach (36°02 ′ 59 ″ N, 120°21 ′ 40 ″ E) in Qingdao , China GoogleMaps .

Etymology: ‘ sinica ’ refers to the fact that the species was first discovered in China.

Description: In vivo, cell about 50–60 × 25–40 µm in size. Body oval in outline with both ends broadly rounded; right margin convex, and widest portion at posterior 1/3 of body length ( Fig. 2A, D–F). Ventral side flat and dorsal side somewhat vaulted ( Fig. 2H). C-shaped CSB 3–4 µm wide, encircled cell perimeter but with a conspicuous gap in posterior 1/3–1/4 of right margin ( Fig. 2B, E, F, M). Extrusomes (or cortex granules?) granule-like, c. 0.5 µm long, densely spaced on dorsal side ( Fig. 2N). Cytostome prominent, positioned at anterior 1/3 of cell; cytopharynx 20 µm long, diagonally oriented, extending to posterior right and surrounded by 14–15 nematodesmal rods. Usually three finger-like protuberances ( Fig. 2A, D), each about 5 µm long, located in middle and posterior region of ventral side. Two contractile vacuoles diagonally located in anterior and posterior quarter, respectively ( Fig. 2K). A single macronucleus about 20 × 11 µm after staining, heteromerous and ellipsoidal, positioned in body centre. Micronucleus not detected. Cilia about 10 µm long. Movement by gliding on substrate.

Somatic kineties divided into preoral and postoral regions at cytostome level. Consistently four preoral kineties, arched along anterior margin of cell ( Fig. 2C, J); 15 postoral rows composed by ten right kineties and five left kineties, and forming a suture posteriorly ( Fig. 2C, L). Two terminal fragments, one antero-dorsally positioned, composed of six kinetosomes ( Fig. 2B, M); the other on anterior left margin of cell, consisting three or four kinetosomes ( Fig. 2C). Equatorial fragment composed of about 13 kinetosomes, positioned next to rightmost postoral ciliary row ( Fig. 2I). Two contractile vacuole pores usually recognizable after protargol impregnation ( Fig. 2C, J).

Perioral kineties comprising one anterior and two posterior rows, all composed by dikinetids and transversely positioned. Anterior row long, and parallel to posterior two ( Fig. 2C, J).