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A new hypotrichous ciliate, Schmidtiella ultrahalophila gen. nov., spec. nov., was isolated from a solar saltern on the island of Sal, Cape Verde. The possession of only one short dorsal kinety clearly distinguishes S. ultrahalophila from other known hypotrichous genera and species. Further diagnostic characters include: a flexible and slender body, an average size of 85 × 15 μm in vivo; a bipartite adoral zone with two hypertrophied frontal adoral membranelles and nine to twelve ventral adoral membranelles; three frontal, one parabuccal, two frontoventral, two or three postoral ventral, and two or three frontoterminal cirri; and marginal cirral rows variable in number, usually one on each side. Ontogenetic data indicate the following: the frontal‐ventral cirri originate from six or five anlagen; the proter inherits the parental adoral zone; the frontal and ventral cirri originate from five or six anlagen; and the marginal cirral rows and the dorsal kinety tend to originate intrakinetally. Additional marginal rows are rarely derived from de novo anlagen. Based on its morphology, morphogenesis and its SSU rRNA phylogenetic placement, the new species should be assigned to the order Sporadotrichida Fauré‐Fremiet, 1961. Due to low taxon sampling, however, its exact position in this order remains enigmatic. [ABSTRACT FROM AUTHOR]

Salinity is an important factor when exploring the limits known for life. Therefore, hypersaline systems have attracted much attention in recent years. In this study, we investigated the protistan diversity and community composition in two natural salt evaporation ponds (27-30% salinity) located in an ancient volcanic crater on the Cape Verde island Sal using high-throughput DNA sequencing. Our study revealed a broad range of protistan taxa and a high taxonomic diversity within the Ciliophora, Dinophyceae, and Chlorophyta. We detected a total of 23 Dinophyceae families, although Dinophyceae were generally considered to be only this diverse in aquatic environments of less than 10% salinity. Moreover, we uncovered a high degree of genetic novelty in this habitat. The mean similarity of all detected OTUs to previously described sequences was only 93.6%. These findings strongly dispute the traditional view that extreme hypersaline environments generally maintain low protistan diversity. A meta-analysis covering our and previously published data from other inland and coastal salt ponds clearly showed that our samples clustered according to salinity and not biogeography. This result further supports the claim that salinity is a major transition boundary for protistan communities, regardless of their biogeographic origin. [ABSTRACT FROM AUTHOR]