Location: Animal Parasitic Diseases LaboratoryTitle: Phylogenetic relationships and taxonomic revision of Paranoplocephala Lühe, 1910 sensu lato (Cestoda, Cyclophyllidea, Anoplocephalidae) Author
Submitted to: Zootaxa
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/20/2014
Publication Date: 10/18/2014
Citation: Haukisalmi, V., Hardman, L., Hoberg, E.P., Henttonen, H. 2014. Phylogenetic relationships and taxonomic revision of Paranoplocephala Lühe, 1910 sensu lato (Cestoda, Cyclophyllidea, Anoplocephalidae). Zootaxa. 3873:371-415. Interpretive Summary: Understanding parasite faunal diversity is fundamental to documenting the role of parasites in the biosphere, and in revealing the intricate histories for host-helminth associations and the biotic and abiotic drivers that have determined and structured these assemblages in space and time. The Paranoplocephala-like tapeworms, numbering about 34 recognized species in rodent hosts, constitute a powerful model for exploring faunal assembly through geographic colonization and switching among hosts across North America and Eurasia during glacial stages of the past 3 million years. We completed new phylogenetic (genealogical, evolutionary history) studies of this diverse assemblage of parasites leading to the first major revision of this group since the 1970's. Phylogenies were based on evaluation of DNA sequences from partial mitochondrial genes. A substantial modification of current taxonomy is proposed with diagnosis of 12 new genera for species that had traditionally been assigned to Paranoplocephala. In clarifying taxonomy we further define critical suites of morphological characters that are in concordance with molecular data, and which serve to provide a clear basis for identification of these diverse parasites. We summarize this information in a synoptic diagnostic key. These studies provide a pathway to explore the intricate geographic relationships for a complex fauna in arvicoline rodents (voles and lemmings) contributing to a broadening baseline for diversity to understand historical generalities about the structure of parasite assemblages among northern mammals including free-ranging and domestic ungulates. Significantly this study contributes to a growing body of work on the importance of climatological drivers as determinants of diversity and geographic distribution, serving to provide a developing analogue for how complex systems respond to accelerating climate change. Results of our research will be widely used by taxonomists working on helminth systematics, biogeographers, and climate modelers, in sectors of the government, universities and NGO's, in seeking to articulate baselines to understand diversity and the environmental outcomes for climate and ecological perturbation.
Technical Abstract: An extensive phylogenetic analysis and genus-level taxonomic revision of Paranoplocephala Lühe, 1910 -like cestodes (Cyclophyllidea, Anoplocephalidae) are presented. The phylogenetic analysis is based on DNA sequences of two partial mitochondrial genes, i.e. cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1), and includes 51 cestode isolates. The revision concerns all 34 Paranoplocephala-like species considered valid, of which 21 species could be included in the molecular phylogenetic analysis. Based on the phylogenetic relationships and main morphological features, with emphasis on the structure of the scolex, suckers and neck, length of the vagina (relative to the cirrus sac) and distribution of testes, 12 new genera are proposed for cestodes traditionally assigned to Paranoplocephala s. l. This results in 22 new combinations. The new genera are: Gulyaevia n. g., Chionomiella n. g., Microtiella n. g., Beringitaenia n. g., Arctocestus n. g., Rauschoides n. g., Arvicoliella n. g., Douthittia n. g., Lemminia n. g., Tenoraia n. g., Nordmanniella n. g. and Cookiella n. g. In addition, Paranoplocephala (s. s.) and Parandrya Gulyaev & Chechulin, 1996 are redescribed; the latter genus is considered valid, although it has been earlier synonymized with Paranoplocephala. A new species (Beringitaenia nanushukensis n. sp.) from Microtus miurus is described. Based on the DNA sequence data, several additional lineages probably representing independent species are identified, but not described as new taxa because of lack of good-quality specimens or absence of reliable morphological differences. A key for the Paranoplocephala-like genera is presented. The patterns of diversity and zoogeography of cestodes representing the “arvicoline clade” (71 species) are complex, involving mechanisms of dispersal, geographic colonization and host switching linking faunas across Eurasia and North America.