Irkana gen. nov. (Ciliophora, Suctorea), a symbiont of the colonial peritrich Carchesium in Lake Baikal

A.W. Jankowski

Proceedings of the Zoological Institute RAS, 2015, 319(1): 40–56 · https://doi.org/10.31610/trudyzin/2015.319.1.40

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Abstract

Elodea canadensis near a wharf in Listvenka bears colonies of Carchesium richly infested with a new species of small suctorians, supposedly modified tokophryids. The description of this suctorian is illustrated with a series of drawings made with the aid of an ocular reticle and thus retaining the exact proportions of the cells, of their tentacles and host stalks; this series shows growth stages and individual variations in cell size, shape, number and distribution of tentacles. Cells are bag-like, with a somewhat erratic distribution of retractile acrotenic tentacles in 2–3, rarely 4 indistinct groups on the cell surface, without actinophores, with an ovoid macronucleus and homogenous attachment disc (fixon), without a stalk; reproduction is by internal budding. New combination: Tetrahymena hydrae (Entz, 1912) Jankowski comb. n. for Balantidium hydrae Entz, 1912 (endoparasite of co-existing Hydra baicalensis).

Key words

Carchesium, Irkana, Peritrichia, Suctorea, symbiosis

Submitted February 25, 2014 · Accepted March 2, 2015 · Published March 25, 2015

References

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