Phylogeny and Morphology of New Diplonemids from Japan

Publication date: Available online 21 February 2018 Source:Protist Author(s): Daria Tashyreva, Galina Prokopchuk, Akinori Yabuki, Binnypreet Kaur, Drahomíra Faktorová, Jan Votýpka, Chiho Kusaka, Katsunori Fujikura, Takashi Shiratori, Ken-Ichiro Ishida, Aleš Horák, Julius Lukeš Diplonemids were recently found to be the most species-rich group of marine planktonic protists. Based on phylogenetic analysis of 18S rRNA gene sequences and morphological observations, we report the description of new members of the genus Rhynchopus − R. humris sp. n. and R. serpens sp. n., and the establishment of two new genera − Lacrimia gen. n. and Sulcionema gen. n., represented by L. lanifica sp. n. and S. specki sp. n., respectively. In addition, we describe the organism formerly designated as Diplonema sp. 2 (ATCC 50224) as Flectonema neradi gen. n., sp. n. The newly described diplonemids share a common set of traits. Cells are sac-like but variable in shape and size, highly metabolic, and surrounded by a naked cell membrane, which is supported by a tightly packed corset of microtubules. They carry a single highly reticulated peripheral mitochondrion containing a large amount of mitochondrial DNA, with lamellar cristae. The cytopharyngeal complex and flagellar pocket are contiguous and have separate openings. Two parallel flagella are inserted sub-apically into a pronounced flagellar pocket. Rhynchopus species have their flagella concealed in trophic stages and fully de...
Source: Protist - Category: Molecular Biology Source Type: research