Maryna ovata (Gelei, 1950) Foissner, 1993

Jung, Jae-Ho & Yeo, Jeong Hyeon, 2020, New record of five ciliate species from temporary ponds on a grass lawn, Journal of Species Research 9 (1), pp. 68-76 : 74-75

4. Maryna ovata (Gelei, 1950) Foissner, 1993

Diagnosis. Size in vivo 37-45 × 23-26 μm (on average 42 × 25 μm, n = 7), 31.1-36.3× 22.2-23.5 μm (on average

34.1 × 22.9 μm) after protargol impregnation; it lives in a hyaline dwelling-tube, however, the tubes adhere to each other, to debris, or to the tubes of coexisting C. mucicola . Body reverse ‘U’ shape, anterior end rounded or slightly tapering, posterior end with distinct uvula, transverse section round to elliptical. Nuclear apparatus composed of a spherical to globular macronucleus (6.2-7.9 × 5.9- 7.8 μm) and spherical to ellipsoidal micronucleus (2.8- 3.3 × 2.4-3.1 μm). Contractile vacuole in uvula without collecting canals. Posterior third of body usually dark at low magnification due to dense yellowish crystals. 31- 40 somatic kineties with spiral course; it should be noted that, as mentioned by Foissner (1993), the spiral course hampers to precisely count the number of kineties; caudal cilia more than two times longer than somatic ones. Oral apparatus above uvula; vestibulum funnel-shaped; left and right polykinetid with similar size.

Distribution. Europe and Korea.

Remarks. According to Foissner (1993), the small ciliate M. ovata can be identified by the elongated caudal cilia, globular macronucleus, contractile vacuole in uvula, and U-shaped body. This species resembles M. rotunda Dingfelder, 1962 , but differs in having U-shaped body (vs. globular). However, the latter species was superficially described, and Foissner (1993) considered it being possibly synonymous with M. ovata . Dunthorn et al. (2012) used two molecular markers for understanding oral evolution of Marynidae sensu lato that resulted in non-monophyly of the group Ilsiella + Maryna , which are classified in the same family ( Lynn, 2008).

Voucher slides. Two slides of protargol impregnated specimens were deposited at National Institute of Biological Resources, Korea (NIBRPR0000110179, NIBRPR 0000110180).