Pleurotricha curdsi ( Shi et al., 2002 ) Gupta et al.,

Min, Kyu-Seok Chae and Gi-Sik, 2022, New record of three oxytrichid ciliates (Ciliophora: Oxytrichidae) from South Korea, Journal of Species Research 11 (4), pp. 287-295 : 290-291

publication ID	https://doi.org/ 10.12651/JSR.2022.11.4.287
persistent identifier	https://treatment.plazi.org/id/039987B0-FFE5-2427-625F-FADDFD22FBEC
treatment provided by	Felipe
scientific name	Pleurotricha curdsi ( Shi et al., 2002 ) Gupta et al.,
status

Treatment

2. Pleurotricha curdsi ( Shi et al., 2002) Gupta et al.,

2003 ( Table 1, Figs. 3-5 View Fig View Fig View Fig )

Allotricha curdsi Shi et al., 2002: p. 397 View in CoL .

Pleurotricha curdsi Gupta et al., 2003: p. 275 View in CoL ; Xu et al., 2015: p. 190, figs. 5A- N, table 2; Lu et al., 2015: p. 3216, fig. 2, table 1.

Korean name. ḆĕọūAEǿAEệ

Material examined. Soil , Gimhae-si, Gyeongsangnam-do, South Korea (35°19 ʹ 1 ʺ N 128°48 ʹ 11 ʺ E, 1), collected by Kyu-Seok Chae in May 2020 GoogleMaps .

Diagnosis of the Korean population. Size in vivo about 160 × 95 μm, broadly ellipsoid body shape; 2 macronuclear nodules and 2-3 micronuclei; contractile vacuole at left of mid-body; 46-53 adoral membranelles; cortical granules absent; 3 frontal cirri; 6 frontoventral cirri; 3-5 postoral ventral cirri; 2 pretransverse cirri; 5 transverse cirri; one buccal cirrus; one left and 2-3 right marginal cirral rows; 4 dorsal and 2 dorsomarginal kineties.

Description. Body size in vivo 110-200 × 50-105 μm, 130-165 × 55-100 μm after protargol impregnation ( Table 1). Body shape broadly ellipsoid to obovate with rigid cortex ( Figs. 3B View Fig , 4A View Fig ). Length to width ratio about 2:1. Contractile vacuole on left side of mid-body, about 20 μm in diameter ( Figs. 3A View Fig , 4B View Fig , arrow). Two macronuclear nodules, with a size of 17-35 × 10-15 μm after protargol preparation ( Figs. 3C View Fig , 5C View Fig , arrow). Two to three micronuclei, 3-5 μm in diameter after protargol preparation ( Figs. 3C View Fig , 5C View Fig , arrowhead). Cortical granules absent. Cytoplasm colorless ( Fig. 4D View Fig ).

Adoral zone of membranelles conspicuous, about 45% of the body length, and composed of 46-53 membranelles ( Figs. 3B View Fig , 5A View Fig , Table 1). Both paroral and endoral membrane curved leftward anteriorly ( Fig. 3B View Fig ). 21-23 frontal-ventral-transverse cirri, including three frontal, one buccal, five frontoventral, three to five postoral ventral, two pretransverse, and five transverse cirri ( Figs. 3B View Fig , 5A View Fig , Table 1). Marginal cirri arranged in one left and two to three right marginal rows, right marginal rows gradually shortened from right to left ( Figs. 3B View Fig , 5A View Fig Table 1). Dorsal ciliature comprising four kineties and two dorsomarginal rows, three caudal cirri located at ends of dorsal kineties 1, 2, 4 on posterior end of cell ( Figs. 3C View Fig , 5B View Fig ).

Distribution. China, India, and South Korea (This study).

Remarks. Pleurotricha curdsi is most similar to P. lanceolata (Ehrenberg, 1835) Stein, 1859 , the type species of the genus Pleurotricha based on their two or more right marginal rows, and three caudal cirri ( Gupta et al., 2003). However, P. curdsi differs from P. lanceolata with respect to the number of frontoventral-transverse cirri (21-23 vs. 17 or 18) ( Gupta et al., 2003; Xu et al., 2015).

The Korean population corresponds to the type population from China, but they are different in the number of adoral membranelles (46-53 vs. 53-61) ( Shi et al., 2002). The Korean population is also similar to the Indian population, except for the number of right marginal rows (2 to 3 vs. 2) ( Gupta et al., 2003).

The 18S rDNA gene sequence of P. curdsi was 1770 bp in length (GenBank accession number: OM212985). The Korean population and others Pleurotricha congeners were monophyletic with high support (97% ML, 1.00 BI) in the phylogenetic tree (arrowhead in Fig. 8 View Fig ). Intraspecific genetic distances among P. curdsi populations were 0.06%-0.12% (1-2 nt difference), and interspecific genetic distances between P. curdsi and P. lanceolata , and between P. curdsi and P. oligocirrata were each 0.19% (3 nt difference) and 0.26% (4 nt difference), respectively.

Deposition. The voucher slide with protargol-impregnated specimens is deposited in the National Institute of Biological Resources in Korea (NIBRPR0000110851).