title: A huge diversity of metopids (Ciliophora, Armophorea) in soil from the Murray River floodplain, Australia. I. Description of five new species and redescription of Metopus setosus Kahl, 1927.
abstract: Six metopid ciliates from soil of the Murray River floodplain in Australia were studied using live observation, various silver impregnation methods, scanning electron microscopy, and multivariate statistics. One of the species is affiliated with M. setosus while the others represent new taxa. Metopus filum nov. spec. is distinguished from most congeners by the slender body, the absence of cortical granules, and the low number of ciliary rows and adoral polykinetids. Metopus palaeformides nov. spec. most resembles Heterometopus palaeformis (Kahl, 1927) Foissner, 2016b but they can be distinguished by body size, the number of adoral polykinetids, and the oral area pattern. Metopus murrayensis nov. spec. is outstanding in having a globular macronucleus surrounded by innumerable refractive granules and a conspicuously thick preoral dome. Metopus rex nov. spec. and M. magnus nov. spec. are easily distinguished from most congeners by their large body size and the shape of the macronucleus. Moreover, M. rex displays up to 30μm long endosymbiotic bacteria while the micronucleus of M. magnus is uniquely situated in a small macronuclear concavity. Multivariate statistics corroborates the distinctness of these six metopid populations.
authors.affiliation: Department of Zoology, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská dolina B-1, 842 15 Bratislava, Slovak Republic. Electronic address: vdacny@fns.uniba.sk.
authors.forename: Peter
authors.initials: P
authors.lastname: Vďačný
authors.affiliation: FB Ecology and Evolution, Faculty of Natural Sciences, Salzburg University, Hellbrunnerstrasse 34, 5020 Salzburg, Austria.
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Foissner
mesh_terms: D001315:Australia; D044822:Biodiversity; D016798:Ciliophora / Q000502:physiology* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D015999:Multivariate Analysis; D010802:Phylogeny; D045483:Rivers; D012987:Soil / Q000469:parasitology*; D013045:Species Specificity
chemical_list: D012987:Soil
keywords: Metopidae; Morphology; Morphometry; Oral area patterns; Soil ciliates; Taxonomy