New Contributions to the Diversity of Hypotrichous Ciliates: Description of a New Genus and Two New Species (Protozoa, Ciliophora)

Abstract

Ciliated protists (ciliates) are extremely diverse and play important ecological roles in almost all kinds of habitats. In this study, two new hypotrichs, Wilbertophrya sinica n. g. and n. sp. and Bakuella xianensis n. sp., from China are investigated. Wilbertophrya n. g. can be separated from related genera mainly by the combination of lacking a buccal cirrus, pretransverse cirri, and caudal cirri, while possessing frontoterminal cirri. Analyses based on morphological and molecular data confirm the validity of the species, W. sinica n. sp., which is characterized as follows: body 50–115 μm × 15–35 μm in vivo; midventral complex comprises four or five cirral pairs only and terminates above mid-body; three frontal, two frontoterminal cirri, and two to four transverse cirri; about 15 macronuclear nodules; colorless cortical granules sparsely distributed. Another new species, B. xianensis n. sp., was isolated from a freshwater wetland and is defined as follows: body 115–150 μm × 40–65 μm in vivo; about 70 macronuclear nodules; dark-brownish cortical granules in groups; midventral complex comprises 8–12 cirral pairs forming a row that terminates posteriorly in mid-body region and two or three short midventral rows that are continuous with the row of midventral pairs; three frontal, four to six frontoterminal, and three to five fine transverse cirri; three bipolar dorsal kineties. Phylogenetic analyses based on small subunit ribosomal DNA (SSU rDNA) sequence data suggest that the new genus Wilbertophrya n. g. belongs to an isolated clade, which might represent an undescribed taxon at the family level, whereas B. xianensis n. sp. groups with several congeners and members of other related genera are within the core urostylids.

Redescription of Bakuella (Bakuella) marina Agamaliev and Alekperov, 1976 (Protozoa, Hypotrichia), With Notes on Its Morphology, Morphogenesis, and Molecular Phylogeny

“…( Pseudobakuella ), respectively. The above results are consistent with those of the previous studies ( Chen et al, 2013 ; Fan et al, 2014 ; Jo et al, 2015 ; Lv et al, 2015 ; Lyu et al, 2018 ; Ma et al, 2021 ).…”

“…(Pseudobakuella), based on the number of frontoterminal cirri (the former has more than two frontoterminal cirri vs. only two in the later). Currently, there are 15 species assigned in this genus (Song et al, 1992;Berger, 2006;Kumar et al, 2010;Chen et al, 2013;Jo et al, 2015;Li et al, 2021;Ma et al, 2021). Among them, molecular data (SSU rDNA) (Eigner and Foissner, 1992;Song et al, 1992;Berger, 2006;Chen et al, 2013Chen et al, , 2020bLi et al, 2021).…”

Morphology and Morphogenesis of Pseudourostyla levis (Ciliophora, Hypotrichia) from River Yamuna, Delhi, India.

“…Urostylids are most diverse and complex groups of hypotrichs but due to lack of sufficient morphogenetic data, their evolutionary relationships are still not clear [13][14][15][16][17][18]. Pseudourostyla was separated from other urostylids on the basis of frontal ciliature, mid ventral complex and presence of two or more rows of left and right marginal cirri, originating from a common primordium which arises within the rightmost row [13,19,20].…”