Otostephanos auriculatus auriculatus

Song, Min Ok & Lee, Chang-Ho, 2021, New records of three monogonont and seven bdelloid rotifers from Korea, Journal of Species Research 10 (4), pp. 392-404 : 398

6. Otostephanos auriculatus auriculatus

( Murray, 1911) ( Fig. 6 )

ḤȇssŀqĒÊệ (ṵḋ)

Habrotrocha auriculata Murray, 1911, p. 16 , pl. 2, figs. 8a, b.

Otostephanos auriculatus auriculatus : Donner, 1965, pp. 98, 99, figs. 74g, h.

Material examined. One specimen sorted out from leaf litter and mosses on rocks at Galcheon-ri, Seo-myeon, Yangyang-gun, Gangwon-do, 37°54′3.0″N, 128°30′6.4″E, 1 August 2020.

Diagnosis. Rostrum short. Rostral lamella bilobed and with wide median interspace between them; interspace slightly bilobed. Corona much wider than cingulum. Papilla on trochal disc rather big. Upper lip with narrow and high median lobe; median lobe triblobed anterioly; as high as trochal discs. Fine ring between corona and upper lip disconnected laterally. Teeth 10/10. Two strong longi- tudinal folds running from the posterior part of trunk to rump dorsally.

Measurements. Total length in creeping 255 μm. Corona width 42 μm. Cingulum width 34 μm. Cingulum pad width 33 μm. Greatest trunk width in feeding 74 μm.

Remarks. The species of Otostephanos has a fine ring between trochal discs and upper lip. In Otostephanos a. auriculatus , the fine ring is disconnected laterally ( Donner, 1965; Murray, 1911).

The general morphology of the Korean specimen agrees well with the original description. Otostephanos a. auriculatus differ from the other subspecies, O. auriculatus bilobatus Hauer, 1939 , by the following characteristics: (1) the median lobe of the upper lip is trilobed anteriorly in O. a. auriculatus , while it is bilobed in O. a. bilobatus, and (2) the median lobe of the upper lip of O. a. bilobatus is much narrower than that of the upper lip of O. a. auriculatus .

This subspecies has been recorded from Africa, Australia, Europe, New Zealand and Pacific Islands ( Donner, 1965; Ricci et al., 2003; Iakovenko et al., 2013), and is newly reported from Asia by the present study.

World distribution. Africa, Australia, Europe, Korea, New Zealand and Pacific Islands.

Deposition. Deposited in the collection of the National Institute of Biological Resources, Incheon, Korea ( KDELIV 0000003121 ) .

Figures

Fig. 6. Otostephanos auriculatus auriculatus(Murray, 1911).A. feeding, dorsal view; B. feeding, dorsal view; C. creeping, dorsal view(Scales: A-C=50 μm).