title: Morphology, ontogenesis and molecular phylogeny of Platynematum salinarum nov. spec., a new scuticociliate (Ciliophora, Scuticociliatia) from a solar saltern.
abstract: Platynematum salinarum nov. spec. was discovered in a hypersaline (∼120 ‰) solar saltern in Portugal. Its morphology,ontogenesis, and 18S rRNA were studied with routine methods. Platynematum salinarum has a size of about 35 m × 18 m and differs from other platynematids (= Platynematum and Pseudoplatynematum) in having an only slightly flattened body without any spines or notches. Both, the oral and somatic infraciliature resemble other platynematids and the tetrahymenidpattern in general. The ontogenesis is scuticobuccokinetal, being unique in generating protomembranelle 1 from kinetids produced by the paroral membrane of the proter and of the scutica. This composite divides transversely: the right half becomes the paroral membrane of the opisthe, the left half transforms to opis the’s adoral membranelle 1. The scutica and the molecular sequence classify P. salinarum into the order Scuticociliatida, family Cinetochilidae. The 18S rRNA sequence shows 92.7%similarity to the closest relative deposited in public databases (the scuticociliate Sathrophilus holtae), and our study provides the first sequence for the genus Platynematum. Experiments at different salinities show growth between 120 ‰ and 300 ‰, survivalat 100 ‰, and cell death around 60 ‰ salinity, characterizing P. salinarum as a true halophile.
authors.affiliation: Universität Salzburg, FB Organismische Biologie, Hellbrunnerstrasse 34, A-5020 Salzburg, Austria. Electronic address: wilhelm.foissner@sbg.ac.at.
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Foissner
authors.affiliation: Inha University, Biological Sciences, 402-251 Incheon, South Korea.
authors.forename: Jae-Ho
authors.initials: JH
authors.lastname: Jung
authors.affiliation: Universität Kaiserslautern, FB Biologie, Erwin-Schrödingerstrasse 14, D-67663 Kaiserslautern, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Filker
authors.affiliation: Universität Kaiserslautern, FB Biologie, Erwin-Schrödingerstrasse 14, D-67663 Kaiserslautern, Germany.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Rudolph
authors.affiliation: Universität Kaiserslautern, FB Biologie, Erwin-Schrödingerstrasse 14, D-67663 Kaiserslautern, Germany.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Stoeck
mesh_terms: D016798:Ciliophora / Q000145:classification* / Q000166:cytology* / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D016054:DNA, Protozoan / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D011174:Portugal; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D012492:Salts / Q000494:pharmacology; D012623:Seawater / Q000469:parasitology*; D013045:Species Specificity
chemical_list: D016054:DNA, Protozoan; D012337:RNA, Ribosomal, 18S; D012492:Salts
keywords: Biodiversity; Cinetochilidae; Extremophile ciliates; Hypersaline ciliates; Platynematum marinum; Portugal