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Three Dysteria species, D. crassipes Claparède & Lachmann, 1859; D. brasiliensis Faria et al., 1922; and D. paracrassipes n. sp., were collected from subtropical coastal waters of the East China Sea, near Ningbo, China. The three species were studied based on their living morphology, infraciliature, and molecular data. The new species D. paracrassipes n. sp. is very similar to D. crassipes in most morphological features except the preoral kinety, which is double-rowed in the new species (vs. single-rowed in D. crassipes ). The difference in the small ribosomal subunit sequences (SSU rDNA) between these two species is 56 bases, supporting the establishment of the new species. The Ningbo population of D. crassipes is highly similar in morphology to other known populations. Nevertheless, the SSU rDNA sequences of these populations are very different, indicating high genetic diversity and potentially cryptic species. Dysteria brasiliensis is cosmopolitan with many described populations worldwide and four deposited SSU rDNA sequences. The present work supplies morphological and molecular information from five subtropical populations of D. brasiliensis that bear identical molecular sequences but show significant morphological differences. The findings of this study provide an opportunity to improve understanding of the morphological and genetic diversity of ciliates.

With highly specialized morphology and unexplored functional capacities, ciliates from extreme habitats are drawing increasing attention. During a microbial investigation of a solar saltern pond (salinity 240‰) on Mallorca, Spain, a previously unknown scuticociliate, Platynematum rossellomorai n. sp. was isolated, cultured and studied using a tripartite approach consisting of a morphological description, a molecular analysis and an ecophysiological characterization. The ciliate has distinct morphological characteristics and its main diagnostic features include a large anteriorly positioned oral area (occupying almost half of the body length), two caudal cilia and a small number of somatic kineties. However, due to the most important generic feature of Cinetochilidae, the consistency of the arrangement of the adoral membranes, the ciliate is classified as a new member of the genus Platynematum. Its 18S rRNA gene sequence shows a sequence similarity of 91.0% to the closest deposited relative, Platynematum salinarum, and a phylogenetic analysis reveals a close relationship to other members of the family Cinetochilidae Perty, 1852. Growth experiments identify the ciliate as a borderline halophile, with a tolerance range between 180 and 280‰ salinity. The ciliate apparently accumulates the compatible solutes glycine betaine and ectoine to counterbalance osmotic stress, however, other osmoregulatory mechanisms are not excluded., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

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., (© 2019 International Society of Protistologists.)

Three new cyrtophorian ciliates isolated from coastal areas of China were described based on morphological and genetic data. The Chlamydodon mnemosyne-like species Chlamydodon similis sp. n. differs from its congeners mainly by its number of somatic kineties. Chlamydodon oligochaetus sp. n. is distinguished from its congeners mainly by having fewer somatic kineties, and/or an elongated body shape. Chlamydodon crassidens sp. n. is characterized mainly by an inverted triangular body shape, a posteriorly interrupted cross-striated band (5-6 μm wide), and a large cytostome. Moreover, we provided small-subunit (SSU) rDNA sequences of C. similis sp. n. and C. oligochaetus sp. n. Maximum likelihood (ML) and Bayesian inference (BI) consistently placed C. similis sp. n. as a sister to C. paramnemosyne, but showed different branching position of C. oligochaetus sp. n., which may be due to a low taxon sampling in the Chlamydodontidae and/or an insufficient resolution of the marker gene at species level., (© 2017 The Author(s) Journal of Eukaryotic Microbiology © 2017 International Society of Protistologists.)

The morphology, ciliary pattern and small subunit rDNA (SSU rDNA) sequences of two new cyrtophorian ciliates, Aegyria foissneri sp. n. and Lynchella minuta sp. n., isolated from brackish waters in southern China, were investigated. Aegyria foissneri sp. n. is characterized as follows: cell size 85-170×45-80μm in vivo; body inverted oval with a protrusion and a dark pigment spot on anterior left part; 42-77 somatic kineties; one preoral and three to six circumoral kineties; five to eight transpodial segments; 31-44 nematodesmal rods; 12-16 contractile vacuoles; and single oval macronucleus. Lynchella minuta sp. n. is distinguished from its congeners by having a cell size of 20-30×15-20μm in vivo, oval body outline; four preoral and 14 or 15 postoral kineties, three circumoral kineties; ca. 11 nematodesmal rods; one finger-like tentacle on the ventral side; and two diagonally located contractile vacuoles. Molecular phylogenetic analyses support the genus assignment of Aegyria foissneri sp. n. and indicate the monophyly of the genus. While Lynchella minuta sp. n. clusters with Coeloperix species, which indicates that Lynchella is non-monophyletic., (Copyright © 2016 Elsevier GmbH. All rights reserved.)

Three cyrtophorian ciliates isolated from brackish biotopes in China, Pseudochilodonopsis quadrivacuolata sp. nov., Pseudochilodonopsis fluviatilisFoissner, 1988 and Pseudochilodonopsis mutabilisFoissner, 1981, were investigated using living observation and protargol-staining methods. P. quadrivacuolata sp. nov. can be characterized as follows: cell size 50-70 × 30-40 μm in vivo; body oval with posterior end rounded; four tetragonally positioned contractile vacuoles; 12-15 nematodesmal rods; five right and six left somatic kineties; terminal fragment positioned apically on dorsal side, consisting of 11-14 basal bodies; four or five fragments in preoral kinety. P. fluviatilis and P. mutabilis were generally consistent with previous descriptions. In addition, a brief revision and a key to Pseudochilodonopsis are presented. The small-subunit (SSU) rRNA gene was also sequenced to support the identification of these species. Phylogenetic analyses based on molecular data indicate that the genera Pseudochilodonopsis and Chilodonella are closely related and both are well outlined; that is, all known congeners for which SSU rRNA gene sequence data are available group together, forming the core part of the family Chilodonellidae.

The living morphology and infraciliature of seven Dysteria species isolated from the seas around China were investigated by observation of both living cells and specimens after protargol impregnation. Dysteria paraprocera sp. n. is characterized as follows: cell size 110-150×30-40μm in vivo; body elongate rectangular and slender; a yellow-brown to dark red coloured pigment spot located at anterior end of body; three right kineties, with rightmost two extending apically to dorsal margin and innermost one starting at level of cytostome; eight or nine short left kineties at equatorial area. Dysteria nabia, D. proraefrons, D. brasiliensis, D. cristata, D. derouxi and D. crassipes basically correspond well with previous studies and therefore only brief descriptions are presented. Discussions of these species are helpful, however, in understanding the circumscription of Dysteria morphotypes. After careful comparison, Dysteria procera sensu Liu et al. (2008, Acta Hydrobiol. Sin. 32 (suppl.), 84-89 (in Chinese with English abstract)) was verified as a new species, D. subtropica sp. n., mainly because the innermost right kinety starts at mid-body. Small-subunit (SSU) rRNA genes were sequenced for four species of Dysteria, namely, D. paraprocera sp. n., D. subtropica sp. n., D. proraefrons and D. nabia. Sequence comparisons and phylogenetic analyses indicate that these species are well outlined and cluster with their congeners., (Copyright © 2015 Elsevier GmbH. All rights reserved.)

This study investigated the morphology and molecular characteristics of three interesting free-living cyrtophorid ciliates, including two new species, isolated from China: Chilodonella parauncinata sp. n. can be identified by its elongated body shape, with a sharp protrusion in the left anterior part, cell size ca. 60 × 25 μm in vivo, five right and 6-7 left kineties with kinetosomes densely arranged, and a curved cyrtos. Chlamydonella irregularis sp. n. differs from its congeners by the oval body shape, cell size 50-60 × 25-40 μm in vivo, irregular shape of macronucleus, 30-40 club-shaped ventral protuberances, and 17 somatic kineties. Two isolates of Chlamydonella derouxi Song, 2003, collected from an intertidal area in Shandong and a mangrove wetland in Guangdong respectively, correspond well with two previous descriptions, but differ in comprising more basal bodies in left and right equatorial fragments and in having more finger-like protuberances on the ventral side. Phylogenetic analyses based on the small subunit rRNA gene sequences showed that C. parauncinata sp. n. clustered with Chilodonella uncinata, but was a well-outlined species of the genus, and C. irregularis sp. n. and C. derouxi grouped in the family Lynchellidae with their congeners to form the monophyletic genus Chlamydonella., (© 2014 The Author(s) Journal of Eukaryotic Microbiology © 2014 International Society of Protistologists.)

The subclass Cyrtophoria is a group of morphologically specialized ciliates with diverse characteristics, which can be found in a variety of aquatic and terrestrial habitats. In the present study, two cyrtophorian ciliates, Aegyria oliva Claparède & Lachmann, 1859 and A. peculiaris sp. nov., isolated from coastal waters of China, were investigated based on microscopic observations of live and protargol-stained specimens, and SSU rRNA gene sequence analyses. For A. oliva, the type species of the genus, detailed morphometric data, and improved diagnosis are provided. The new species, Aegyria peculiaris sp. nov. is characterized by a body size of 70–115 × 30–65 μm in vivo, an inverted oval body shape with a protrusion at the anterior left and a posterior bulge on the dorsal side, 45–58 somatic kineties, 31–46 nematodesmal rods, 4–6 transpodial segments, and about six contractile vacuoles. Phylogenetic analyses unveiled a close relationship between the newly identified species and A. foissneri, thereby confirming the monophyly of the genus Aegyria. [ABSTRACT FROM AUTHOR]

The subclass Cyrtophoria are a group of morphologically specialized ciliates which mainly inhabit soil, freshwater, brackish water, and marine environments. In this study, we revise more than 50 publications on the taxonomy, phylogeny, and ecology of cyrtophorian ciliates in China since the first publication in 1925, most of which were carried out in coastal areas. The research history can be divided into three periods: the early stage, the Tibet stage, and the molecular stage. To date, 103 morpho-species (147 isolates) have been formally recorded in China, with ciliature patterns described for 82 of them. A species checklist and an illustrated identification key to the genera are provided. A total of 100 small subunit rDNA sequences have been obtained for 74 taxonomic hits (lowest taxonomic rank to species or genus). These sequences are used for the study of molecular phylogeny. Based on these morphological data and molecular phylogeny analyses, we synthesize the understanding of the phylogeny of cyrtophorian ciliates. We hypothesize that the key evolutionary event of cyrtophorian ciliates lies in the separation of the stomatogenesis zone (postoral kineties) from the left kineties, namely, the formation of an independent "sexual organelle". We, furthermore, briefly summarize the ecological features of cyrtophorian ciliates and provide a comprehensive bibliography of related research from China. Finally, we give an outlook on the future research directions of these taxa. [ABSTRACT FROM AUTHOR]

Ciliates occur in the blowholes of marine mammals, but our understanding of their biology is poor. Consequently, we investigated an infestation of ciliates in an unhealthy, captive beluga whale that was exhibiting accelerated breathing, leukocytosis and expulsion of unusually large amounts of viscous sputum. This sputum contained ~104 ciliates mL-1 (when healthy, numbers were ten- to 100-fold lower). One known ciliate species, Planilamina ovata , is fully characterized, and a new species, Kyaroikeus paracetarius sp. nov. , is here described. The new species is established based on its larger number of left kineties over its only congener. Sequences of small-subunit rDNA, large-subunit rDNA and ITS1-5.8S-ITS2 regions of these two taxa were used in phylogenetic analyses, inferring that Kyaroikeus and Planilamina have close affinity with the free-living family Dysteriidae, contradicting their morphology-based assignment to the family Kyaroikeidae. We suggest that Kyaroikeidae be relegated to subfamily status. Finally, by comparing parasitic species with free-living taxa, we suggest how these ciliates have adapted to their unique environment and how they may have initially invaded the host. We provide essential data and concepts for the continued evaluation of ciliate-parasites in whale blowholes. [ABSTRACT FROM AUTHOR]

The ciliate genus Chlamydodon is characterized by a unique cross-striated band (CSB) along the cell perimeter. To date, more than 15 nominal species have been assigned to this genus, all of which are exclusively from marine or brackish water. In the present work, we have revised the genus according to the available data and suggest an illustrated key to aid species diagnosis. In addition, the systematic relationships of chlamydodontid congeners were analysed based on SSU rRNA gene sequences, indicating that all congeners belong to a well-defined clade. Furthermore, we investigated three species from coastal areas of China, including two new species, Chlamydodon wilberti sp. nov. and C. bourlandi sp. nov., using morphological and phylogenetic criteria. Chlamydodon wilberti sp. nov. is characterized by a cell size of 65-105  ×  35-60 µm, a complete CSB, and 38-49 somatic kineties. Chlamydodon bourlandi sp. nov. has a cell size of 150-250  ×  65-150 µm, a complete CSB, a reddish to violet cell colour, 83-97 somatic kineties, and 40-68 contractile vacuoles. As a further contribution, a well-studied species, C. triquetrus (Müller, 1786) Kahl, 1931, is also re-described. www.zoobank.org/urn:lsid:zoobank.org:pub:B83A5466-9D2B-4502-9A23-F16A61D48172. [ABSTRACT FROM AUTHOR]

Abstract: Three new cyrtophorian ciliates isolated from coastal areas of China were described based on morphological and genetic data. The Chlamydodon mnemosyne‐like species Chlamydodon similis sp. n. differs from its congeners mainly by its number of somatic kineties. Chlamydodon oligochaetus sp. n. is distinguished from its congeners mainly by having fewer somatic kineties, and/or an elongated body shape. Chlamydodon crassidens sp. n. is characterized mainly by an inverted triangular body shape, a posteriorly interrupted cross‐striated band (5–6 μm wide), and a large cytostome. Moreover, we provided small‐subunit (SSU) rDNA sequences of C. similis sp. n. and C. oligochaetus sp. n. Maximum likelihood (ML) and Bayesian inference (BI) consistently placed C. similis sp. n. as a sister to C. paramnemosyne, but showed different branching position of C. oligochaetus sp. n., which may be due to a low taxon sampling in the Chlamydodontidae and/or an insufficient resolution of the marker gene at species level. [ABSTRACT FROM AUTHOR]

In the last two decades, cyrtophorian ciliates have been revealed to demonstrate a high species diversity. But this group remains difficult to study, mainly because of their low abundance and relatively few taxonomically informative morphological characters. As a contribution to the taxonomy of cyrtophorians, here we investigate three Dysteria species based on their live morphology, ciliary pattern, and molecular phylogeny. Dysteria ozakii nom. nov. can be recognized by its elongate body shape and four right kineties, including three frontoventral kineties. A neotype has to be fixed for the species as no type materials were deposited. The other two species, D. brasiliensis Faria et al., 1922 and D. compressa (Gourret & Roeser, 1886) Kahl, 1931, are redescribed and supplementary information for each is supplied. Phylogenetic analyses based on small-subunit (SSU) rRNA gene sequences support the validity of the species. In addition, four species of bacterial epibionts were observed on the surface of the three Dysteria spp. The identities of these bacterial species are discussed based on the newly obtained 16S rRNA gene sequences. [ABSTRACT FROM AUTHOR]