Molecular characterization of Ichtyobronema hamulatum (Moulton, 1931) (Nematoda: Quimperiidae), a common parasite of burbot Lota lota (Linnaeus) (Actinopterygii: Lotidae)

Abstract

SummaryThe phylogenetic analysis of partial SSU, LSU (rDNA) and COI (mtDNA) sequences was performed for the quimperiid nematode Ichtyobronema hamulatum, a common parasite of the burbot Lota lota. The study of SSU (for 2007 bp long alignment) has shown that in all kinds of analyses I. hamulatum cluster with Paraquimperia africana (Quimperiidae), while another quimperiid, Paraseuratum sp., unites in a separate clade with Spectatus spectatus (Kathlaniidae). Both groups do not form direct phylogenetic links with the rest of seuratoid nematodes (i.e. Cucullanidae and Seuratidae). Obtained data (for 1080 bp long alignment) exhibit the phylogenetic affi nity of I. hamulatum and P. africana with kathlaniids of the genus Falcaustra. The analysis of LSU sequences has revealed that I. hamulatum occupies the basal position in relation to all other members of Spirurina and Rhabditina.

Pathobiology and first report of larval nematodes (Ascaridomorpha sp.) infecting freshwater mussels (Villosa nebulosa, Unionidae), including an inventory of nematode infections in freshwater and marine bivalves

“…As an aside, Cosmocercoidea and Seuratoidea (and their respective families) were paraphyletic or polyphyletic in the recovered tree, and Cucullanidae was recovered as an early branching lineage (monophyletic). These results corroborate earlier findings regarding the phylogenetic interrelationships of these taxa (Pereira et al., 2015; Choudhury and Nadler, 2016; Sokolov and Malysheva, 2017). The superfamilies Seuratoidea (Cucullanidae, Quimperiidae, Seuratidae, et al.)…”

“…The phylogenetic analysis recovered them all as sharing a recent common ancestor: the nematode infecting V. nebulosa was sister to Ichthyobronema hamulatum (Seuratoidea: Quimperiidae; GenBank Accession Number KY476351 ex. burbot, Lota lota [Linnaeus, 1758] [Gadiformes: Lotidae] from Russia) (Sokolov and Malysheva, 2017) (Fig. 12).…”

“…A preliminary NCBI BLAST (https://blast.ncbi.nlm.nih.gov) search showed high genetic similarity (>97%) between the new sequence and those of Cosmocercoidea and Seuratoidea; therefore representatives of these superfamilies were used in the phylogenetic analysis. The dataset for phylogeny consisted of 23 taxa belonging to Atractidae, Cosmocercidae and Kathlaniidae (Cosmocercoidea), and Cucullanidae, Quimperiidae and Seuratidae (Seuratoidea) plus Zeldia punctata (Thorne, 1925) (Cephaloboidea: Cephalobidae) as outgroup, chosen according to previous studies (Choudhury and Nadler, 2016; Pereira and Luque, 2017; Sokolov and Malysheva, 2017). Sequences with less than 800bp and without genetic overlapping were excluded.…”

Twenty Years after De Ley and Blaxter—How Far Did We Progress in Understanding the Phylogeny of the Phylum Nematoda?

“…Phylogenetic relationships within the suborder Spirurina remain insufficiently known, and the latest 18S rRNA-based phylogenies [ 13 , 50 , 51 ] present very confusing results that are difficult to interpret and describe, with many paraphyletic and polyphyletic families ( Figure 4 ). In part this is due to presence of “rogue” taxa, the impact of which on “labelling” the phylogeny with taxonomic names (family names) has been discussed by Nadler et al [ 52 ] specifically in the context of Spirurina.…”