Stephanoceros, Ehrenberg, 1832

Davies, Natalie, Lafleur, Alexandre, Hochberg, Rick, Walsh, Elizabeth J. & Wallace, Robert L., 2024, Key to sessile gnesiotrochan rotifers: Families, monospecific species in Flosculariidae, species of Atrochidae, Conochilidae, and Limnias, Zootaxa 5397 (4), pp. 497-520 : 503

Dichotomous key to species of genus Stephanoceros

1 Setae on lobes in spiral fans; body length 1500–2500 µm; oviparous. ( Fig. 3A ).............. fimbriatus (Goldfuss, 1820) [Information on the myo-anatomy and events during metamorphosis of Stephanoceros were presented by Hochberg and Hochberg (2017). Remane (1933) illustrated the growth of the gelatinous tube. Yang et al. (2021) provided information on the ultrastructure of the gelatinous secretions of this species and its congener. Gilbert (1993) reviewed literature that described regeneration in this species.]

1’ Setae on lobes not in spiral fans; setae in two long rows, distally finer and longer; body length 800–1350 µm; oviparous. ( Fig. 3B ).............................................................................. millsii (Kellicott, 1885) [Ciliation of S. fimbriatus is described and figured by Wright (1952) and Koste (1978) and that of S. millsii by Koste (1978).]

Figures

FIGURE 3. Representative Bauplans of the anterior ends of Stephanoceros (A, B) and Collotheca (C, D). A. Stephanoceros fimbriatus. B. Stephanoceros millsii. C. Collotheca campanulata. D. Collotheca ornata. Symbols: e = embryo; d= debris; gt = gelatinous tube; i = infundibulum; l = lobes; s = setae; t = tentacles. Bars: A, B = 500 µm C, D = 100 µm.