Complete mitochondrial genomes and nuclear rRNA operons of eight geographically distinct isolates of the Asian fish tapeworm Schyzocotyle acheilognathi (syn. Bothriocephalus acheilognathi), representing the parasite's global diversity spanning four continents, were fully characterised using an Illumina sequencing platform. This cestode species represents an extreme example of a highly invasive, globally distributed pathogen of veterinary importance with exceptionally low host specificity unseen elsewhere within the parasitic flatworms. In addition to eight specimens of S. acheilognathi, we fully characterised its closest known relative and the only congeneric species, Schyzocotyle nayarensis, from cyprinids in the Indian subcontinent. Since previous nucleotide sequence data on the Asian fish tapeworm were restricted to a single molecular locus of questionable phylogenetic utility-the nuclear rRNA genes-separating internal transcribed spacers-the mitogenomic data presented here offer a unique opportunity to gain the first detailed insights into both the intraspecific phylogenetic relationships and population genetic structure of the parasite, providing key baseline information for future research in the field. Additionally, we identify a previously unnoticed source of error and demonstrate the limited utility of the nuclear rRNA sequences, including the internal transcribed spacers that has likely misled most of the previous molecular phylogenetic and population genetic estimates on the Asian fish tapeworm.
- MeSH
- biodiverzita MeSH
- Cestoda klasifikace genetika MeSH
- cestodózy parazitologie veterinární MeSH
- Cyprinidae parazitologie MeSH
- DNA helmintů genetika MeSH
- druhová specificita MeSH
- fylogeneze MeSH
- fylogeografie MeSH
- geny rRNA * MeSH
- nemoci ryb parazitologie MeSH
- operon MeSH
- ribozomální proteiny genetika MeSH
- vysoce účinné nukleotidové sekvenování metody MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
In this study, the relationships of the cestode order Bothriocephalidea, parasites of marine and freshwater bony fish, were assessed using multi-gene molecular phylogenetic analyses. The dataset included 59 species, covering approximately 70% of currently recognised genera, a sample of bothriocephalidean biodiversity gathered through an intense 15year effort. The order as currently circumscribed, while monophyletic, includes three non-monophyletic and one monophyletic families. Bothriocephalidae is monophyletic and forms the most derived lineage of the order, comprised of a single freshwater and several marine clades. Biogeographic patterns within the freshwater clade are indicative of past radiations having occurred in Africa and North America. The earliest diverging lineages of the order comprise a paraphyletic Triaenophoridae. The Echinophallidae, consisting nearly exclusively of parasites of pelagic fish, was also resolved as paraphyletic with respect to the Bothriocephalidae. Philobythoides sp., the only representative included from the Philobythiidae, a unique family of parasites of bathypelagic fish, was sister to the genus Eubothrium, the latter constituting one of the lineages of the paraphyletic Triaenophoridae. Due to the weak statistical support for most of the basal nodes of the Triaenophoridae and Echinophallidae, as well as the lack of obvious morphological synapomorphies shared by taxa belonging to the statistically well-supported lineages, the current family-level classification, although mostly non-monophyletic, is provisionally retained, with the exception of the family Philobythiidae, which is recognised as a synonym of the Triaenophoridae. In addition, Schyzocotyle is resurrected to accommodate the invasive Asian fish tapeworm, Schyzocotyle acheilognathi (Yamaguti, 1934) n. comb. (syn. Bothriocephalus acheilognathi Yamaguti, 1934), which is of veterinary importance, and Schyzocotyle nayarensis (Malhotra, 1983) n. comb. (syn. Ptychobothrium nayarensis Malhotra, 1983). The genus is morphologically characterised by a wide, heart-shaped scolex with narrow, deep bothria.
- MeSH
- Cestoda anatomie a histologie klasifikace genetika izolace a purifikace MeSH
- cestodózy parazitologie veterinární MeSH
- fylogeografie * MeSH
- molekulární sekvence - údaje MeSH
- nemoci ryb parazitologie MeSH
- ryby MeSH
- sekvenční analýza DNA MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH