title: Using DNA-barcoding for sorting out protist species complexes: a case study of the Nebela tincta-collaris-bohemica group (Amoebozoa; Arcellinida, Hyalospheniidae).
abstract: Species identification by means of morphology is often problematic in protists. Nebela tincta-collaris-bohemica (Arcellinida) is a species complex of small to medium-sized (ca.100 μm) testate amoebae common in peat bogs and forest soils. The taxonomic validity of characters used to define species within this group is debated and causes confusion in studies of biogeography, and applications in palaeoecology. We examined the relationship between morphological and genetic diversity within this species complex by combined analyses of light microscopy imaging and Cytochrome Oxidase Subunit 1(COI) sequences obtained from the same individual amoeba cells. Our goals were (1) to clarify the taxonomy and the phylogenetic relationships within this group, and (2) to evaluate if individual genotypes corresponded to specific morphotypes and the extent of phenotypic plasticity. We show here that small variations in test morphology that have been often overlooked by traditional taxonomy correspond to distinct haplotypes. We therefore revise the taxonomy of the group. We redefine Nebela tincta (Leidy) Kosakyan et Lara and N. collaris (Ehrenberg 1848) Kosakyan et Gomaa, change N. tincta var. rotunda Penard to N. rotunda (Penard 1890), describe three new species: N. guttata n. sp. Kosakyan et Lara, N. pechorensis n. sp. Kosakyan et Mitchell, and N. aliciae n. sp. Mitchell et Lara.
authors.affiliation: Laboratory of Soil Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland. anush.kosakyan@unine.ch
authors.forename: Anush
authors.initials: A
authors.lastname: Kosakyan
authors.forename: Fatma
authors.initials: F
authors.lastname: Gomaa
authors.forename: Edward A D
authors.initials: EA
authors.lastname: Mitchell
authors.forename: Thierry J
authors.initials: TJ
authors.lastname: Heger
authors.forename: Enrique
authors.initials: E
authors.lastname: Lara
mesh_terms: D016000:Cluster Analysis; D058893:DNA Barcoding, Taxonomic / Q000379:methods*; D003576:Electron Transport Complex IV / Q000235:genetics; D016840:Lobosea / Q000145:classification* / Q000166:cytology / Q000235:genetics*; D008853:Microscopy; D024101:Mitochondrial Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D017422:Sequence Analysis, DNA
chemical_list: D024101:Mitochondrial Proteins; D003576:Electron Transport Complex IV