Ref ID : 7708
Michele Laval-Peuto; Sexual Reproduction in Favella ehrenbergii (Ciliophora, Tintinnina) taxonomical Implications. Protistologica XIX(4):503-512, 1983
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Conjugations have occurred in the in mass cultures of Favella ehrenbergii, devoted to the study of lorica construction. They lasted about 10 hours and came with changes in the behaviour of the tintinnids, which are described. The ex-conjugants did not survive in culture. Among the pairs of conjugants, all displayed cells of the same volume, but some owned different loricae, considered to be different species or genera in the classification currently used. Analysis of the data of literature shows that isogamic conjugations in the plankton of tintinnids with identical loricae is a frequent event, while the fusion of macrogametes and microgametes, obtained in culture in Tintinnopsis beroidea (Gold and Pollingher, 1971) remains an exception, the meaning of which is not yet understood. Meanwhile the presence of different loricae in the conjugants of F. ehrenbergii does not represent an anisogamy, for all the different types of loricae were associated at random, according to their frequency in the cultured population. The results obtained confirm preceding conclusions (Laval-Peuto 1981, 1982) about the existence of numerous phenotypes of loricae in F. ehrenbergii and about the need for revising the classification of Tintinnina only based on this much too variable element. Here sexual reproduction allows a satisfactory definition of the species Favella ehrenbergii in accordance with Mayr's (1963, 1970) biological concept of the species.