How Phylogenies Inferred from 46 Mitochondrial Genomes Informed the Systematics of the Australasian Genus of Ticks, Bothriocroton, with the Description of Three New Species

Abstract

Background: We revised the taxonomy and identification of the species of the genus Bothriocroton in light of entire mitochondrial genomes and nuclear rRNA genes, scanning electron microscopy, and light microscopy. Methods: (i) phylogenetic trees inferred from entire mitochondrial genomes and nuclear rRNA genes, (ii) species delimitation analyses (ABGD and bPTP), and (iii) the study of morphology by scanning electron microscopy (SEM) and light microscopy. Results: The most complete picture of the Bothriocroton ticks so far. Thirty-five new mitochondrial genomes and 27 partial 18S–28S rDNA sequences were generated. Phylogenetic analyses recovered seven well-supported clades corresponding to species-level lineages. Intraspecific genetic divergence ranged from 0.14 to 1.16%, whereas interspecific divergence ranged from 4.94 to 21.75%. Three new species were described, and the morphological diagnosis of other species was improved by redescribing two other species. In addition, we updated and improved the morphological dichotomous keys to male and female ticks. Conclusions and prospects: The routine genotyping of Bothriocroton ticks to identify species and to confirm provisional identifications of species from their morphology is an alternative to the morphological identification of closely related Bothriocroton ticks.