Abstract Background Various ecological groups of earthworms very likely constitute sharply isolated niches that might permit speciation their symbiotic ciliates, even though no distinct morphological features appear to be recognizable among ciliates originating from different host groups. The nuclear highly variable ITS1–5.8S-ITS2 region and the hypervariable D1/D2 28S rRNA gene have proven useful tools for delimitation species boundaries in closely related free-living ciliate taxa. In...

Abstract The digestive tract of oligochaetes harbours a diverse ciliate community embracing plagiotomids, nyctotherids, astomes, and hysterocinetids. Although several hundred intestinal species are known, only two hysterocinetids have been reported from the intestine Holarctic lumbricid earthworms hitherto. present study is focused on taxonomy, morphology, molecular phylogeny lumbricid-dwelling taxa, insufficiently known Protoptychostomum simplex Hysterocineta bellerophon sp. nov., detected...

Four earthworm species, the endogeic Octolasion tyrtaeum (Savigny, 1826), anecic Lumbricus terrestris Linnaeus, 1758 as well epigeic Eisenia fetida 1826) and Dendrobaena veneta (Rosa, 1886), were examined for presence of astome ciliates. Based on integrative taxonomic approach, five ciliate species recognized in their gastrointestinal tracts: Metaradiophrya lumbrici (Dujardin, 1841), M. varians (de Puytorac, 1954), Anoplophrya (Schrank, 1803), A. vulgaris de 1954 nodulata 1841). Their...

Coevolution of endosymbionts with their hosts plays an important role in the processes speciation and is among most fascinating topics evolutionary biology. Astome ciliates represent interesting model for coevolutionary studies because they are so tightly associated host organisms that completely lost cell oral apparatus. In present study, we used five nuclear markers (18S rRNA gene, ITS1–5.8S–ITS2 region, 28S gene) two mitochondrial genes (16S gene cytochrome c oxidase subunit I) to explore...

Hybridization is an important evolutionary process that can fuel diversification via formation of hybrid species or lead to fusion previously separated lineages by forming highly diverse complexes. We provide here the first molecular evidence hybridization in wild populations ciliates, a group free-living and symbiotic eukaryotic microbes. The impact was studied on model Plagiotoma , obligate endosymbiont digestive tube earthworms, using split decomposition analyses networks, 2D modeling...

Four common earthworm species, the anecic Lumbricus terrestris, endogeic Octolasion tyrteum as well epigeic Eisenia fetida and Dendrobaena veneta, were examined for presence of microbial gut symbiont Plagiotoma lumbrici. The evolutionary origin this endobiotic microbe was reconstructed, using 18S rRNA gene, ITS1-5.8S-ITS2 region, first two domains 28S gene. lumbrici exclusively detected in terrestris. Multigene analyses ITS2 secondary structure robustly determined phylogenetic home...