Habrotrocha pavida Bryce, 1915

Song, Min Ok, 2014, Eight new records of monogonont and bdelloid rotifers from Korea, Journal of Species Research 3 (1), pp. 53-62 : 59

7. Habrotrocha pavida Bryce, 1915 ( Fig. 4 )

Habrotrocha pavida Bryce, 1915, p. 637 , pl. 38, fig. 2;

Bartos ˇ, 1951, p. 318, figs. 21A-C; Bartos ˇ, 1959, p. 144, figs. 17D-F; Donner, 1950, pp. 316-318, figs. 15a-e; Donner, 1965, pp. 40-41, Fig. 21.

Material examined. 2 specimens, a mountain in Mongsanpo, Seosan-si, Chungcheongnam-do (mosses and leaf litter, Min Ok Song), 14 April , 2013 .

Description. Inhabiting irregular shaped shelter or nest of mucus, detritus and extruded food pellets. Body with smooth surface. Rostrum rather short. Rostral lamella small, narrower than rostrum end and bilobed. Corona wider than cingulum pad. Upper lip lower than sulcus, rimmed, arched, and with triangular median lobe; each side of upper lip expanded like auricle. Disc retractor bilobed with convex sides and as high as trochal discs. Antenna rather short and with very prominent process on each side; each protuberance with expanded end. Pharyngeal tube as long as trophi length. Dental formula 4/4. Trunk spindle-shaped and with distinct longitudinal folds. Rump abruptly tapering into foot. Foot with 3 segments and 3 toes; first foot segment with a round process dorsally. Spurs finger-shaped, long, thin, about 3 times as long as its base, tapering gradually from base to blunt tip; interspace 2 times as wide as spur base.

Body length (in creeping) 280-285 μm. Corona width 47 μm. Cingulum pad width 35 μm. Antenna segment width 35 μm. Spur length 19 μm.

Distribution. Germany, Czech Republic, England, Austria, Rumania, North America and Korea.

Remarks. New to Asia. This species is very similar to H. gracilis in the general body structure and the same habit of taking shelter or nest in any available aggregations of debris, but it is distinguished from the latter by the following characteristics; (1) Cingulum of the present species has bulging lateral margins as well as a triangular median lobe, while that of the latter does not, (2) The first foot segment of the present species has a round process dorsally, while that of the latter has two transverse protuberances anterodorsally, (3) Disc retractor of the present species does not have any process medially, while that of the latter has three ones, and (4) Spurs of the present species are longer and thinner than those of the latter.

Figures

Fig. 4. Habrotrocha pavida Bryce, 1915. A. creeping, dorsal view. B. creeping, lateral view. C. feeding head and neck, dorsal view. D. spurs and toes, ventral view (Scales: A-C=50 μm; D=20μm).