Rimaleptus similis ( Foissner, 1995 ) Vd

Kim, Ji Hye & Jung, Atef Omar and Jae-Ho, 2020, Brief description of 18 newly recorded ciliate species from soil and inland waters (Protozoa, Ciliophora) in South Korea, Journal of Species Research 9 (3), pp. 251-268 : 261-262

13. Rimaleptus similis ( Foissner, 1995) Vd ̓ačný &

Foissner, 2012 ( Fig. 13 )

Material examined. Terrestrial moss collected from Mt. Yeonhwasan , Sinbun-ri , Yeonghyeon-myeon, Goseong-gun, Gyeongsangnam-do, Korea (N 35°4 ʹ 6.4 ʺ, E 128°13 ʹ 53.5 ʺ) on 4 February 2019 .

Diagnosis. Size in vivo 260 - 280 × 50 - 60 μm and about 135 × 35 μm after protargol impregnation (n = 3). Body narrowly dileptid with rounded posterior end, proboscis length 130 - 170 μm in vivo. A single micronucleus in between two oblong macronuclear nodules. Contractile vacuoles located on dorsal side in a row. Two types of extrusomes attached to proboscis and oral bulge: type I rod-shaped, about 9.0 × 0.7 μm in size; type II oblong, about 3 μm in length. 29 - 36 somatic kineties; preoral kineties oblique, ordinarily to narrowly spaced, each usually composed of two or three narrowly spaced kinetids.

Distribution. Australia, Costa Rica, Kenya, Namib Desert, and Korea

Remarks. The Korean population of R. similis corresponds to the original population ( Foissner, 1995; Vd̓ačný and Foissner, 2012). Rimaleptus similis is similar to the most related species, R. orientalis (Song et al., 1988) Vd ̓ačný & Foissner, 2012, in the arrangement of contractile vacuoles (only on dorsal side), the shape of macronuclear nodules (ellipsoid to oblong), and in the short brush bristles (~3 μm) but they differ mainly in the shape (rod-shaped vs. broadly fusiform) and size (6 - 10 μm vs. 1 - 2 μm) of oral extrusomes (Vd̓ačný and Foissner, 2012).

Voucher slides. Two slides with protargol-impregnated specimens were deposited at the Nakdonggang National Institute of Biological Resources (NNIBRPR11690, NNI BRPR11691).

Figures

Fig. 13. Rimaleptus similis from life (A, B, E) and after protargol impregnation (C, D). A. Typical body shape in vivo. B. Distribution of contractile vacuoles. C. Somatic and oral ciliature. D. Details of oral ciliature. E. Single spherical micronucleus between two macronuclear nodules and two kinds of oral extrusomes. CK, circumoral kinety; CV, contractile vacuoles; MA, macronuclear nodule; MI, micronucleus; PR, preoral kinety. Scale bars=100 μm (A); 50 μm (C, E).