Matthew D. Shaw

Evidence of a Spotted Fever-Like Rickettsia and a Potential New Vector from Northeastern Australia

Abstract A spotted fever-like rickettsia was identified in a Hemaphysalis tick by polymerase chain reaction (PCR) amplification and sequencing of the 16S rDNA, ompA, and ompB genes. A comparison of these nucleotide sequences with those of other spotted fever group (SFG) rickettsiae revealed that the Hemaphysalis tick rickettsia was distinct from other previously reported strains. Phylogenetic analysis based on both ompA and ompB also indicates that the strain’s closest relatives are the agents of Thai tick typhus (Rickettsia honei strain TT-118) and Flinders Island spotted fever (R. honei). This study represents the first report of an R. honei-like agent from a Hemaphysalis tick in Australia and of a spotted fever group rickettsia from Cape York Peninsula, Queensland.

Re-evaluation of Pseudoparasitus (Gymnolaelaps) annectans (Womersley): a new genus and two new species (Acari: Mesostigmata: Laelapidae)

Pseudoparasitus (Gymnolaelaps) annectans (Womersley) and two new species are assigned to a new genus, Nidilaelaps. Nidilaelaps has a number of important differences from Pseudoparasitus and other genera that Nidilaelaps annectans has been previously assigned to, but shares characters with Australopapuan vertebrate-associated taxa, particularly the “Androlaelaps” ulysses species group and Laelapsella Womersley. Nidilaelaps annectans is common in a variety of mammal and bird nests and also in forest litter. The two new species (N. holdsworthi sp. nov., N. lisae sp. nov.) are recorded from mammals, birds, or their nests in Papua New Guinea or Australia. Nidilaelaps is inferred to be endemic to the Australopapuan region. The presence of N. annectans in other regions is suggested to be due to relatively recent colonisation, facilitated by its many phoretic associations, particularly with synanthropic rodents.

Ulyxes, a new Australopapuan mite genus associated with arboreal nests (Acari: Laelapidae)

As part of a survey of mammal and bird nests, new species, new male stages, and some feeding observations have been collected from what was formerly called the Androlaelaps ulysses group. As many features of this group are consistently different from Androlaelaps, and also from Haemolaelaps where it was formerly placed, this group is here elevated to Ulyxes new genus, and U. autolycus, U. euryclea, and U. theoclymenus are described as new species. This genus has a broad range of feeding behaviour spanning intranasal parasitism, nidicolous parasitism, and at least one species is a nidicolous predator. Its host range is broad; two new species are shown here to cohabit with parrots while most remaining species associate with mammals. In contrast to the variation in feeding behaviour, Ulyxes spp are associated with a narrow range of nest types, being confined to arboreal nests, usually tree hollows (rarely fallen logs), and on the parrot or mammal hosts that use them. Ulyxes spp show a remarkable variability in male cheliceral development, which assorts according to feeding behaviour. There is a strong contrast between male chelicerae of predatory and parasitic species that has not been previously observed in such a compact dermanyssine genus. Previously male cheliceral morphology was thought to be conservative enough to provide diagnostic characters at suprageneric rank. For systematics, these findings complicate previous attempts to recognise male mouthparts as reliable features marking higher-level natural groups that include dermanyssoid vertebrate parasites. For evolutionary studies, this may be relevant in seeking examples of transitions to, or away from, parasitism.