Morphology and SSU rD NA Sequence Analysis of Two Hypotrichous Ciliates(Protozoa, Ciliophora, Hypotrichia) Including the New Species Metaurostylopsis parastruederkypkeae n.sp.

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(r RNA) 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 r DNA 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.

The Morphology and Phylogeny of Three Diophrys Ciliates Collected from the Subtropical Waters of China, Including a New Species (Ciliophora;Euplotia)

Three Diophrys species,D.quadrinucleata n.sp.,D.oligothrix Borror,1965 and D.scutum(Dujardin,1841)Kahl,1932,were identified from the subtropical brackish waters in China,their morphology was investigated using live observation and protargol impregnation.D.quadrinucleata n.sp.can be distinguished from the congeners by four ellipsoidal macronuclear nodules.Phylogenetic analyses show that the three species with single marginal cirrus are closely related,namely D.quadrinucleata n.sp.,D.apoligothrix Song et al.,2009 and D.japonica Hu,2008.Our population of D.oligothrix corresponds very well with previous populations in both living morphology and ciliature.However,the SSU rDNA sequences of three well-described populations differ from each other by 11 to 18 nucleotides,indicating that there might be cryptic species in D.oligothrix.Moreover,we provided a detailed description of the symbiotic bacteria/archaeobacteria(?)concentrated on the back surface of D.scutum based on the present population,which was either overlooked or misinterpreted as cortical granules previously.

Taxonomic Clarification of A Well-Known Pathogenic Scuticociliate,Miamiensis avidus Thompson&Moewus,1964(Ciliophora,Scuticociliatia)

Miamiensis avidus Thompson & Moewus,1964,is a cosmopolitan and well-known marine pathogenic ciliated protist.However,the taxonomy of this species up to now has remained controversial,especially with respect to the validity of the morphologically similar species,Philasterides dicentrarchi,which was considered as a junior synonym of M.avidus.In this study,a population of M.avidus was collected from the skin of pharaoh cuttlefish(Sepia pharaonis) cultured near the East China Sea,Ningbo,China and its morphology and phylogeny were investigated in detail based on living characters,infraciliature,small subunit(SSU) r DNA and ITS1-5.8 S-ITS2 region sequences.In addition,the morphometrics of a previously reported free-living population,collected from the Bohai Sea,were rechecked and analyzed.We compared the present two isolates with all historic populations of M.avidus and P.dicentrarchi,and found that their morphological characters were either highly similar or exactly identical,indicating that they are the same morphospecies.However,the phylogenetic analyses based on SSU r DNA or ITS1-5.8 S-ITS2 region sequences revealed that most M.avidus and P.dicentrarchi populations formed one clade,and the two isolates of M.avidus from Weifang and American Type Culture Collection clustered in another clade,which indicated that there might be cryptic species in Miamiensis avidus.