Morphology and SSU rDNA sequence analysis of two hypotrichous ciliates (Protozoa, Ciliophora, Hypotrichia) including the new species Metaurostylopsis parastruederkypkeae n. sp.

Abstract

The morphology and phylogeny of two hypotrichous ciliates, Metaurostylopsis parastruederkypkeae n. sp. and Neourostylopsis flavicana (Wang et al., 2011) Chen et al., 2013 were investigated based on morphology, infraciliature and the small subunit (SSU) ribosomal RNA gene (rRNA) sequence. The new species, M. parastruederkypkeae n. sp. was identified according to its characteristics: body shape ellipsoidal, size about (165-200) × (45-60) µm in vivo, cell color reddish; two types of cortical granules including wheat grain-like and yellow-greenish larger ones along the marginal cirri rows and dorsal kineties and dot-like and reddish smaller ones, grouped around marginal cirri on ventral side and arranged in short lines on dorsal side; 26-41 adoral membranelles; three frontal and one parabuccal, five to seven frontoterminal, one buccal, and three to six transverse cirri; seven to thirteen midventral pairs; five to nine unpaired ventral cirri, five to seven left and three to five right marginal rows; and three complete dorsal kineties. Phylogenetic analysis based on SSU rDNA sequences showed that both Metaurostylopsis and Neourostylopsis are monophyletic. As the internal relationship between and within both genera are not clear, further studies on the species in these two genera are necessary. The key characteristics of all known twelve Metaurostylopsis-Apourostylopsis-Neourostylopsis species complex were updated.

Ontogeny and Phylogeny of a New Hypotrichous Ciliate (Protista, Ciliophora), Metaurostylopsis alrasheidi n. sp., With Establishment of a New Genus Monourostylopsis n. gen.

“…Consistent with previous studies (Shao et al, 2008a;Chen et al, 2011;Song et al, 2011;Lu et al, 2016), we confirm the monophyly of genus Metaurostylopsis based on the phylogenetic analyses in present work.…”

“…Metaurostylopsis parastruederkypkeae is distinguished from M. alrasheidi n. sp. by having reddish body (vs. yellowgreenish), reddish cortical granules (vs. yellow-greenish), more frontoterminal cirri (5-7 vs. 3-4), more adoral membranelles (28-47 vs. 19-30), and more cirri in midventral row (5-9 vs. 3-4) (Lu et al, 2016).…”

“…was isolated from freshwater habitat. All the other Metaurostylopsis species have been reported in marine or brackish water (Song et al, 2001;Lei et al, 2005;Berger, 2006;Shao et al, 2008a,b;Chen et al, 2011;Lu et al, 2016). These studies have shown that Metaurostylopsis species can be found in a variety of habitats (Figure 8).…”

“…Original Chen et al, 2011Song et al, 2001Lu et al, 2016Song and Wilbert, 2002Lei et al, 2005Shao et al, 2008bJung et al, 2011Pan et al, 2016Wang et al, 2011Zhang et al, 2018Chen et al, 2013Lei et al, 2005Shao et al, 2008a AZM Monourostylopsis n. gen.…”

Multigene‐based phylogeny of Urostylida (Ciliophora, Hypotrichia), with establishment of a novel family

“…Furthermore, Neourostylopsis did not cluster with Metaurostylopsis in all trees although they are morphologically similar. This is due to (i) the frontal cirri are arranged in a corona in Neourostylopsis , whereas there are only three enlarged frontal cirri in Metaurostylopsis ; and; (ii) the midventral complex is composed of midventral pairs and midventral rows in Metaurostylopsis , whereas only midventral pairs are present in Neourostylopsis (Chen, Huang, & Song, ; Chen, Shao et al., ; Lu, Wang, Huang, Shi, & Chen, ; Pan et al., ; Shao, Miao et al., ; Wang, Hu, Huang, Al‐Rasheid, & Warren, ).…”