Habrotrocha gracilis quadridens Schulte, 1954

Song, Min Ok & Lee, Chang-Ho, 2020, Descriptions of two new species of Philodina (Rotifera, Bdelloidea), with notes on seven rare bdelloids from Korea, Zootaxa 4772 (2), pp. 253-276 : 266-267

Habrotrocha gracilis quadridens Schulte, 1954

Figure 8a

Material. One specimen sorted out from mosses around a mountain in Jangyeol-ri, Bukpyeong-myeon, Jeongseongun, Gangwon-do.

While Habrotrocha gracilis gracilis Montet doesn't have any process on the base of sulcus, this subspecieslevel taxon has a small finger-shaped process between sulcus base and upper lip when feeding. In addition, the dental formula is 5/6 or 4/ 6 in H. gracilis gracilis , while it is 4/ 4 in H. gracilis quadridens .

The general morphology of the Korean specimen conforms to that of the type specimens except that the dental formula of the Korean specimen was 4/3.

This subspecies-level taxon is very rare and has never been reported again after the description from Germany by Schulte (1954) until the present study.

Measurements. Total length in feeding 144–201 μm. Corona width 27 μm. Cingulum width 27 μm. Cingulum pad width 26 μm. Greatest neck width in feeding 33 μm. Greatest trunk width in feeding 54 μm. Trophi length 14 μm.

Figures

FIGURE 8. (a) Habrotrocha gracilis quadridens Schulte, 1954, feeding head and neck, dorsal view; (b) Habrotrocha ligula aligula Burger, 1948, feeding head and neck, dorsal view (scale bars: a–b = 25 μm).