On the importance of attentive reading of research articles: the case study of Frontonia (Peniculia, Oligohymenophora, Ciliophora) species descriptions and redescriptions

A commonly encountered problem of ignoring or inattentive reading of scientific articles by some protistologists of the past and present has been revealed using the case study of taxonomy of the ciliate genus Frontonia. The comparison between materials from literature and own investigations allowed the author to conclude that F. vernalis Ehrenberg, 1833 cannot to be a valid species and assume that it is rather a cluster of closely related freshwater ciliates with one contractile vacuole and a stable ability to accommodate green algae as the cytoplasmic symbionts. “F. vernalis”, as described by Bullington (1939), was shown to have little in common with the original description by Ehrenberg and most likely is a brackishwater ciliate similar to F. fusca. F. oculiaris described by the same author (Bullington, 1939) is obviously F. fusca, and the name “F. oculiaris” should be considered as a younger synonym of the latter. Thus, redescription of F. oculiaris (Pan et al., 2013b) should be treated just as a morphological study of the local Chinese population of F. fusca. The redescription of F. canadensis from brackish waters by the same authors can be considered as a description of a new species that has little in common with the original description of this freshwater ciliate (Roque and Puytorac, 1972). Recent phylogenetical reconstructions indicate the necessity to split Frontonia into several genera.