Habrotrocha ligula loxoglotta De Koning, 1947

Zeng, Yue, Wei, Nan, Wang, Qing, Iakovenko, Nataliia S., Li, Ying & Yang, Yufeng, 2020, Bdelloid rotifers (Rotifera, Bdelloidea) of China: diversity and new records, ZooKeys 941, pp. 1-23 : 1

Habrotrocha ligula loxoglotta De Koning, 1947 Figure 4 ; Table 3

Materials.

Five specimens found in mosses on rock from Southwest China (YN5) (Table 2 ).

Description.

Body slender and transparent, integument smooth. Rostrum long and strongly bent ventrally. Rostral lamellae divided into two semi-circular lobes and wider than the anterior rim of rostrum. Head similar to hexagon, HW 89% of HL. Corona slightly narrower than collar, with papillae clearly seen in the middle of each trochus, CW 97% of HW. Trochal discs separated by a narrow, V-shaped sulcus, in which a cylindrical ligula bends obliquely to the dorsal side (Fig. 4F, G ). A slight contraction near the tip which then forms a small papilla on the tip of the ligula , attaining the level of the discs at the inner side (Fig. 4D, E ). Upper lip a flat bow. Neck also bent ventrally when animal creeps. The first pseudosegment of neck slightly narrower than the head at the corners of the mouth, not distinct from head and trunk. A pair of lateral cuticular bulges on the dorsal antenna pseudosegment. Antenna with two segments, its length 30-40% of the bearing pseudosegment width.

Trunk slender and cylindrical, TrL 59-67% of TL. Rump conical, with both pseudosegments somewhat swollen and strong arched up dorsally and roofing the foot, the posterior rim of the second pseudosegment creased, RL 8-10% of TL.

Foot short with three pseudosegments, FL 6-8% of TL. Bulbous spurs short and triangular shape, with distinct tips and wide interspace, base swollen. The width of interspace 114% of SL, 97% of the swollen width. Three stout unsegmented toes of the same length. Trophi small, dental formula 3/3.

Measurements.

TL 186 ± 43 μm, NL 27 ± 3 μm, TrL 119 ± 37 μm, RL 156 ± 2 μm, RW 22 ± 7, FL 12 ± 2 μm, SL 4 ± 2 μm, RaL 13 ± 1 μm, TrW 5.6 ± 0.5 μm.

Remarks.

Habrotrocha ligula loxoglotta was originally described from Holland (De Koning 1947), later reported from beech-oak needle-litter in Germany, from dry mosses in France ( Donner 1951) and from mosses in Austria ( Kutikova 2005). In this study, it was found for the first time in China (Yunnan Province) as well as in the Oriental region.

Figures

Figure 4. Habrotrocha ligula loxoglotta De Koning 1947 A, B habitus, creeping, dorsal view C rostrum, lateral view D, E head, dorsal view F, G head, with ligula sloping obliquely to the dorsal side, lateral view. Scale bars: 50 μm (A, B), 10 μm (C-G).