Sterkiella multicirrata Li et al., 2018

Min, Kang-San Kim and Gi-Sik, 2018, Brief morphological description of stichotrichid ciliates (Ciliophora: Stichotrichia) from Korea, Journal of Species Research 7 (4), pp. 323-332 : 329

9. Sterkiella multicirrata Li et al., 2018 ( Fig. 9 )

Material examined. Soil sample from Bangeo-dong, Ulsan, Korea (35°28ʹ56ʺN, 129°25ʹ54ʺE), on November 2015 .

Diagnosis. Body broadly elliptical, size in vivo 120- 165 × 50-90 μm, semirigid; cortical granules lacking; 4 macronuclear nodules with about 4 micronuclei; about 50 adoral membranelles; more than 18 frontal-ventral-transverse cirri, 3 frontal, 1 buccal, 1 parabuccal, 1 IV/3, 1 or no postoral ventral, 1 or no pretransverse ventral, and 4 or 5 transverse cirri; 2 frontoventral cirral rows (FVR) (3 or 4 cirri in FVR1; 5 or 6 cirri in FVR2); 1 left (about 26 cirri) and 1 right (about 30 cirri) marginal cirral rows; 6 dorsal kineties (4 dorsal and 2 dorsomarginal kineties); 3 caudal cirri.

Remarks. The Korean population of Sterkiella multicirrata differs from its congeners by having the more than 20 frontal-ventral-transverse (FVT) cirri (vs. 17 or 18) ( Chen et al., 2015; Kumar et al., 2015). The increased number of FVT cirri is a representative feature of the genus Gastrostyla , and the phylogenetic tree showed that S. multicirrata has a close relationship with the G. steinii group (Kumar et al., 2015; Li et al., 2018). These two genera share many morphological traits (inflexible body, lack of cortical granules, and six dorsal kineties), and only differ in the number of FTV cirri (usually 18 in Sterkiella vs. more than 18 in Gastrostyla ). Based on the above mentioned findings, we supposed that the location of S. multicirrata is intermediated to these two genera regarding evolution.

Deposition. Two slides (NIBRPR0000107255, NIBRPR0000107269) have been deposited at the National Institute of Biological Resources (NIBR), Korea.

Figures

Fig. 9. Photomicrographs of Sterkiella multicirrata from life (A, B) and after protargol impregnation (C, D) specimens. (A-C) Ventral views. (D) Dorsal view. Scale bars=100 μm.