Plagiocampa rouxi Kahl, 1926

Omar, Atef & Jung, Ji Hye Choi and Jae-Ho, 2023, New record of ten ciliate species (Protozoa, Ciliophora) from South Korea, Journal of Species Research 12 (1), pp. 95-108 : 101-102

6. Plagiocampa rouxi Kahl, 1926 ( Fig. 6 )

Material examined. Water sample collected from a temporary puddle from Baugil , Gangneung-Wonju National University , Jibyeon-dong , Gangneung-si, Gangwon-do, Korea (37°46 ʹ 28 ʺ N, 128°51 ʹ 54.20 ʺ E) on June 4, 2021 .

Diagnosis. Size 35 - 45 × 20 - 25 μm in vivo and 25 - 32 × 18 - 22 μm after protargol impregnation (n = 11); body obovate to ellipsoid with posterior end more broadly rounded than anterior end; single globular macronucleus about 8 μm in diameter, with a single or several nucleoli, in or posterior to mid-body, micronucleus spherical, about 2 μm in diameter and near or attached to macronucleus; cytoplasm studded with ring-shaped, colorless granules especially in anterior half of body; contractile vacuole in posterior body end; 18 or 19 somatic ciliary rows; 15 - 18 kinetids in each somatic kinety; a single caudal cilium up to 18 μm long in vivo; oral opening in center of anterior pole surrounded by 7 - 10 dikinetids (circumoral kinety), each dikinetid associated with an oral flap about 2 μm long in vivo; 3 adoral membranelles (brosse).

Distribution. Cosmopolitan.

Remarks. The Korean population of Plagiocampa rouxi is very similar to the three populations described by Foissner (1978; 1984; 2016). Plagiocampa rouxi was described several times and show some variations especially in the number of somatic kineties, i.e., 17 - 18 ( Foissner, 1978), 13 - 16 ( Foissner, 1984), and 13 - 15 ( Foissner, 2016). The most similar species to P. rouxi is P. difficilis Foissner, 1981 . However, P. difficilis is smaller than P. rouxi and has fewer circumoral dikinetids. Foissner (2016) suggests that P. difficilis could be a junior synonym of P. rouxi ( Foissner, 1981) .

Voucher slides. One slide with protargol-impregnated specimens was deposited at the National Institute of Biological Resources, Korea (NIBRPR0000111069).

Figures

Fig. 6. Plagiocampa rouxi in life (A-C) and after protargol impregnation (D-H). A-C, Lateral views showing the ellipsoidal and obovate body shape, the cytoplasm studded with ring-shaped granules especially in anterior half, the nuclear apparatus, the oral flaps surrounding the oral opening, the single caudal cilium, and the posteriorly located contractile vacuole. D, H, Apical views showing the circumoral kinety consisting of dikinetids and the brosse consisting of three adoral membranelles. E-G, Dorsal (E) and lateral (F, G) views showing the somatic ciliature and the nuclear apparatus. AM, adoral membranelles (brosse); CC, caudal cilium; CK, circumoral kinety; CV, contractile vacuole; FV, food vacuoles; G. cytoplasmic granules; MA, macronucleus; MI, micronucleus; OF, oral flaps. Scale bars 20 μm.