Title

Validity of the Diplostomoidea and Diplostomida (Digenea, Platyhelminthes) Upheld in Phylogenomic Analysis

Authors

Sean A. Locke, University of Puerto Rico - Mayaguez
Alex Van Dam, University of Puerto Rico - Mayaguez
Monica Caffara, Alma Mater Studiorum University of Bologna - Italy
Hudson Alves Pinto, Universidade Federal de Minas Gerais - Brazil
Danimar Lopez-Hernandez, Universidade Federal de Minas Gerais - Brazil
Christopher Blanar, Nova Southeastern UniversityFollow

Document Type

Article

Publication Date

10-19-2018

Publication Title

International Journal of Parasitology

Keywords

Strigeida, Diplostomida, Phylogenomics, Metacercaria, Nuclear-mitochondrial discordance, Cotylurus, Hysteromorpha, Alaria

ISSN

0020-7519

Abstract

Higher systematics within the Digenea, Carus 1863 have been relatively stable since a phylogenetic analysis of partial nuclear ribosomal markers (rDNA) led to the erection of the Diplostomida Olson, Cribb, Tkach, Bray, and Littlewood, 2003. However, recent mitochondrial (mt) genome phylogenies suggest this order might be paraphyletic. These analyses show members of two diplostomidan superfamilies are more closely related to the Plagiorchiida La Rue, 1957 than to other members of the Diplostomida. In one of the groups implicated, the Diplostomoidea Poirier, 1886, a recent phylogeny based on mt DNA also indicates the superfamily as a whole is non-monophyletic. To determine if these results were robust to additional taxon sampling, we analyzed mt genomes from seven diplostomoids in three families. To choose between phylogenetic alternatives based on mt genomes and the prior rDNA-based topology, we also analyzed hundreds of ultra-conserved genomic elements (UCEs) assembled from shotgun sequencing. The Diplostomida was paraphyletic in the mt genome phylogeny but supported in the UCE phylogeny. We speculate this mitonuclear discordance is related to ancient, rapid radiation in the Digenea. Both UCEs and mt genomes support the monophyly of the Diplostomoidea and show congruent relationships within it. The Cyathocotylidae Mühling, 1898 are early diverging descendants of a paraphyletic clade of Diplostomidae Poirier, 1886, in which are nested members of the Strigeidae Railliet, 1919; the results support prior suggestions that the Crassiphialinae Sudarikov, 1960 will rise to the family level. Morphological traits of diplostomoid metacercariae appear to be more useful for differentiating clades than those of adults. We describe a new species of Cotylurus Szidat, 1928, resurrect a species of Hysteromorpha Lutz, 1931, and find support for a species of Alaria Schrank, 1788 of contested validity. Complete rDNA operons from seven diplostomoid species are provided as a resource for future studies.

Comments

©2018 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

NSUWorks Citation

Locke, Sean A.; Alex Van Dam; Monica Caffara; Hudson Alves Pinto; Danimar Lopez-Hernandez; and Christopher Blanar. 2018. "Validity of the Diplostomoidea and Diplostomida (Digenea, Platyhelminthes) Upheld in Phylogenomic Analysis." International Journal of Parasitology , (). doi:10.1016/j.ijpara.2018.07.001.

ORCID ID

0000-0002-4900-3099

DOI

10.1016/j.ijpara.2018.07.001