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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Otostephanus

Otostephanos Milne, 1916 (ref. ID; 7849) (= Otostephanus)

Order Philodinida: Family Habrotrochidae (ref. ID; 6565)

ref. ID; 1923

Sides of coronol pedicels with shelf-like membrane. In drying mosses. (ref. ID; 1923)

ref. ID; 7849

This genus is characterzied by three toes (Fig.9b), and differs from the similar genus Habrotrocha by a dorsally and ventrally opening ring positioned under the pedicles of the trochal discs. (ref. ID; 7849)
  1. Otostephanos jersabeki Koste, 1996 (ref. ID; 7849 original paper)
  2. Otostephanos donneri Bartos, 1959 (ref. ID; 7849)
  3. Otostephanos monteti Milne, 1916 (ref. ID; 7849)
  1. Otostephanus auriculatus (Murray, 1911) (ref. ID; 1345, 1923, 2757)
    Syn; Habrotrocha auriculata Murray, 1911 (ref. ID; 1345, 2757)
  2. Otostephanus auriculatus var. bilobatus Hauer, 1939 (ref. ID; 1345, 2271, 3149 original paper)
  3. Otostephanus cuspitiabris de Koning, 1947 (ref. ID; 1345)
  4. Otostephanus donneri nom. nov. Bartos, 1959 (ref. ID; 3688)
  5. Otostephanus kostei Donner (ref. ID; 1474 original paper)
  6. Otostephanus macrantennus de Koning, 1947 (ref. ID; 1345)
  7. Otostephanus monteti Milne, 1916 (ref. ID; 1345, 2269, 2640, 3688)
    Syn; Habrotrocha torquata Montet, 1915 (ref. ID; 1345); Habrotrocha torquata var. Montet, 1915 (ref. ID; 3688)
  8. Otostephanus mundiformis de Koning, 1947 (ref. ID; 1345)
  9. Otostephanus torquatus (Bryce, 1913) (ref. ID; 1345, 1474, 2562, 3136, 3149, 3688) reported author and year? (ref. ID; 2972)
    Syn; Callidina elegans Ehrenberg, 1832 (ref. ID; 3688); Habrotrocha torquata Bryce, 1913 (ref. ID; 1345, 3136, 3149, 3688); Otostephanus torquatus Milne, 1916 (ref. ID; 1345, 3136)

Otostephanos jersabeki Koste, 1996 (ref. ID; 7849 original paper)

Descriptions

These animals were frequent in the sample. As a result of their triangule-shaped upper lip, they are similar to Otostephanos donneri Bartos (1959) and to some varieties of O. monteti Milne (1916). However, the form of the spurs is different and the bridge between the trochal discs is dome-shaped. Most cospicuous, however, is the triangle-shaped upper lip which at the top was framed by a thick bulge. The trophi has the toothformula 7/7 (Fig.9). The total length of this strange species is 300 µm when creeping. In Fig.9 a feeding (rotating) specimen with a length of 200 µm is presented. In my opinion, this bdelloid rotifer has not been described yet. (ref. ID; 7849)

Etymology

This species was dedicated to Dr. Christian Jersabek, University of Slazburg, who provided me with this sample. (ref. ID; 7849)

Examined materials

A soil sample out of a dried rockpool (lithotelma) on a dolomit hill in the Etosha National Park, N-Namibia, South Africa. (ref. ID; 7849)

Otostephanus auriculatus var. bilobatus Hauer, 1939 (ref. ID; 1345, 2271, 3149 original paper)

Descriptions

In size rather variable, brown in colour with light longitudinal folds, trunk, foot and spurs lightly granulated. Dorsal antenna of medium length. The head with the typical 'ears' of the species, discs wider than the head, the upper lip terminating in a tongue-shaped formation with a thickened support, and a notch in the anterior edge and reaching to the level of the discs. Large mastax with ten or more teeth all fairly fine but with the first four slightly heavier than the remainder, which diminished in thickness to the rear. Spurs small, conical, slightly cut-out with interspace present but only small. (ref. ID; 2271)
  • Egg: Egg elliptical, 62x88 µm. (ref. ID; 2271)

    Measurements

    Animal 1st sample: Length of creeping animal 290; length of feeding animal 190-230; length of between the anterior edge of the discs and the mastax 50; width across the trochal discs 50; width across the neck segment 38; length of the unci 21 µm. Animal 2nd sample: Length of creeping animal 450; length of feeding animal 314; length of between the anterior edge of the discs and the mastax 88; length of the unci 32 µm. (ref. ID; 2271)

    Otostephanus torquatus (Bryce, 1913) (ref. ID; 1345, 1474, 2562, 3136, 3149, 3688) reported author and year? (ref. ID; 2972)

    Synonym

    Habrotrocha torquata Bryce, 1913 (ref. ID; 1345, 3136, 3149); Otostephanus torquatus Milne, 1916 (ref. ID; 1345, 3136)

    Descriptions

    The body is of medium size. The wheel-organ is as broad as the neck or it is slightly broader than the neck. The wheel-discs are more or less dorsally reverted. The upper lip is very high. It is not cut out, but the tip of it is a little reverted. The lower lip is unusually large and protrudes in a spoonlike shape. The dorsal antenna is long. On the wheel-pedicels the cuticular rings in the half level of pedicels very well developed. The foot is four-jointed, but is short. On the first foot-joint sits a dorsal knob. The spurs are short, divergent, and conical in size. The dorsal plicae on the preanal segment are very well developed. D.f.: 6/6 or it is higher. (ref. ID; 3136)

    Measurements

    The length of the body 410 µm, usually the individuals are much shorter (320 up to 350 µm). (ref. ID; 3136)