Molecular and comparative morphological analysis of central European parasitic flatworms of the superfamily Brachylaimoidea Allison, 1943 (Trematoda: Plagiorchiida)

Abstract

The Brachylaimoidea are digenean parasites of vertebrates, including humans, domestic animals, poultry and wild game. Numerous Brachylaimoidea, particularly adults of Brachylaima and Leucochloridium, are difficult to identify to species. We provide and analyse sequences of two nuclear (18S rDNA, ITS2) and two mitochondrial (CO1, ND1) DNA loci of central European species of the Brachylaimoidea, namely Leucochloridium holostomum, Leucochloridium paradoxum, Leucochloridium perturbatum, Leucochloridium subtilis, Leucochloridium vogtianum, Urotocus rossitensis, Urogonimus macrostomus, Michajlovia migrata, Leucochloridiomorpha lutea, Brachylaima arcuatus, Brachylaima fuscata and Brachylaima mesostoma. We identified three clades in the genus Leucochloridium, which do not correspond to the previously suggested subgenera Neoleucochloridium, Papilloleucochloridium and Leucochloridium. We reject classification of Urotocus and Urogonimus in Leucochloridiinae, and, instead, re-establish the subfamilies Urotocinae and Urogoniminae. We synonymize the genus Renylaima with the genus Brachylaima. We reject M. migrata as a member of Leucochloridiinae sensu stricto or Brachylaimidae suggested by some previous authors. We found that the previously sequenced Glaphyrostomum sp. does not cluster with any hitherto sequenced Brachylaimidae. We also provide comparative measurements of the examined central European Brachylaimoidea, address the the specificity of their localization in the host and discuss their host-specific prevalence and intensity of infections based on the extensive dataset of birds examined in 1962-2015.

Testing the higher-level phylogenetic classification of Digenea (Platyhelminthes, Trematoda) based on nuclear rDNA sequences before entering the age of the ‘next-generation’ Tree of Life

“…These studies have resulted in more stable classification schemes of genera within families and families within superfamilies of the subclass Digenea. For example, at the superfamily level, the studies of Microphalloidea (Tkach et al, 2003), Lepocreadioidea Odhner, 1905(Bray et al 2009, Brachylaimoidea (Heneberg et al, 2016) Echinostomatoidea Looss, 1899 (Tkach et al, 2016), and the recent study of Hemiuroidea by Sokolov et al (2018), can be highlighted. Additionally, at the family level, several studies have determined the inter-relationships among genera and the re-organization of subfamilies, such as the study by Tkach et al (2001) with Omphalometridae Looss, 1899 by Choudhury et al (2007) Atopkin et al (2019) with Haploporidae.…”

The Complete Mitochondrial Genome of the Caecal Fluke of Poultry, Postharmostomum commutatum, as the First Representative from the Superfamily Brachylaimoidea

“…The superfamily Brachylaimoidea has potential veterinary importance and complex taxonomic history. Currently, the superfamily Brachylaimoidea contains at least 20 valid species that consist of parasites of mammals and birds (Heneberg et al, 2016). Despite their importance, no mt genome had been sequenced and characterized for any members of the superfamily Brachylaimoidea.…”

Brachylaima ezohelicis sp. nov. (Trematoda: Brachylaimidae) found from the land snail Ezohelix gainesi , with a note of an unidentified Brachylaima species in Hokkaido, Japan

“…Phylogenetic relationships of brachylaimids were inferred by sequences of 28S rDNA and cox1, using an unknown species found in this study and related taxa published in DNA databases [29,30,31,32]. The NJ phylogenetic trees of the two genes strongly suggested that the unknown species belongs to the genus Brachylaima, although the number of taxa available for the tree construction was insufficient ( Supplementary Fig.…”