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The largely unique fauna of ticks in Australia and Papua New Guinea (PNG) has been studied for 250 years. Here, we briefly review the early stages of tick taxonomy in the region, then focus on the activities of five people who contributed much to our knowledge of ticks in Australasia during the second half of the 20th century: F.H.S Roberts, David H. Kemp, Douglas E. Moorhouse, Nixon Wilson and Harry Hoogstraal. We provide biographical notes on each and collated publication lists for Roberts, Kemp and Moorhouse. We recognize three eras of tick taxonomy in Australia. First, an era that we refer to as "colonial tick taxonomy", where ticks were sent from the European colonies to taxonomists in Europe. Second, a brief but significant era that we refer to as "endemic tick taxonomy" defined by the works of F.H.S. Roberts. Thirdly, a final phase of "colonial taxonomy" where ticks were described by workers in the USA. In PNG there has been no phase of endemic tick taxonomy and, while Australian workers are once again describing new tick species, in PNG the USA continues to make the most significant contributions. Through this work, we now see Australasia as one of the "theatres of evolution" of Bothriocroton and Archaeocroton, the Amblyomma-like ticks without eyes. We briefly discuss the current hypotheses for the theatre of evolution of the Ixodida, consider the 22 genus and subgenus-level entities of the Prostriata (Ixodinae) as provisional biological entities, and provide observations on tick phylogenetics and future research. Finally, we outline additional genetic evidence, from a recent whole-transcriptome study, for the two clades of the subfamily Ixodinae (Prostriata), the Australasian Ixodes and all other Ixodes. [ABSTRACT FROM AUTHOR]

The present work is an update and a substantial expansion of Barker & Walker (2014). Barker & Walker (2014) dealt with 16 species of particular importance to domestic animals and humans whereas the present work deals with all 125 of the species known from Australasia; that is Australia, New Zealand, the island of New Guinea, Sulawesi, and the islands of the western Pacific. These comprise 102 species of ixodid (hard) ticks and 23 species of argasid (soft) ticks.

To investigate the evolution pattern and phylogenetic utility of duplicate control regions (CRs) in mitochondrial (mt) genomes, we sequenced the entire mt genomes of three Ixodes species and part of the mt genomes of another 11 species. All the species from the Australasian lineage have duplicate CRs, whereas the other species have one CR. Sequence analyses indicate that the two CRs of the Australasian Ixodes ticks have evolved in concert in each species. In addition to the Australasian Ixodes ticks, species from seven other lineages of metazoa also have mt genomes with duplicate CRs. Accumulated mtDNA sequence data from these metazoans and two recent experiments on replication of mt genomes in human cell lines with duplicate CRs allowed us to re-examine four intriguing questions about the presence of duplicate CRs in the mt genomes of metazoa: (1) Why do some mt genomes, but not others, have duplicate CRs? (2) How did mt genomes with duplicate CRs evolve? (3) How could the nucleotide sequences of duplicate CRs remain identical or very similar over evolutionary time? (4) Are duplicate CRs phylogenetic markers? It appears that mt genomes with duplicate CRs have a selective advantage in replication over mt genomes with one CR. Tandem duplication followed by deletion of genes is the most plausible mechanism for the generation of mt genomes with duplicate CRs. Once duplicate CRs occur in an mt genome, they tend to evolve in concert, probably by gene conversion. However, there are lineages where gene conversion may not always occur, and, thus, the two CRs may evolve independently in these lineages. Duplicate CRs have much potential as phylogenetic markers at low taxonomic levels, such as within genera, within families, or among families, but not at high taxonomic levels, such as among orders.