Macrotrachela insulana Donner, 1962

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 : 264-265

Macrotrachela insulana Donner, 1962

Figure 6 a–b

Material. Five specimens found in mosses around Hwanseongul area, Singi-myeon, Samcheok-si, Gangwon-do.

This species is very rare and has been reported only from Brazil ( Donner 1980) after the description from Mallorca island, Spain ( Donner 1962).

The general morphology of the Korean specimens coincides well with the original description except the location of two small processes which were described to be on sulcus base by Donner (1962). According to the observations of the Korean specimens, the two small processes were on the disc retractor instead of sulcus base. It seemed that Donner (1962; 1980) mistook the positions of the processes during observations. As Donner (1962) mentioned, these two processes could be observed in dorsolateral view only ( Fig. 6a ). Donner (1962) observed that when the Spanish specimens contracted, they were covered with very thin shells and debris. The Korean specimens were not observed in shells.

Measurements. Total length in creeping 351–359 μm. Corona width 70 μm. Cingulum width 57 μm. Cingulum pad width 54 μm. Greatest neck width in creeping 56 μm. Greatest trunk width in feeding 88 μm. Greatest trunk width in creeping 66 μm. Trophi length 22 μm. Spur length 7.4 μm.

Figures

FIGURE 6. Macrotrachela insulana Donner, 1962. (a) feeding head and neck, dorsolateral view; (b) foot, spurs and toes, ventral view. Macrotrachela petulans Milne, 1916. (c) foot, spurs and toes, ventral view; (d) feeding head and neck, dorsal view (scale bars: a, d = 25 μm; b, c = 10 μm).