Haemaphysalis longicornis (Acari: Ixodidae), the Asian longhorned tick, is native to East Asia, but has become established in Australia and New Zealand, and more recently in the United States. In North America, there are other native Haemaphysalis species that share similar morphological characteristics and can be difficult to identify if the specimen is damaged. The goal of this study was to develop a cost-effective and rapid molecular diagnostic assay to differentiate between exotic and native Haemaphysalis species to aid in ongoing surveillance of H. longicornis within the United States and help prevent misidentification. We demonstrated that restriction fragment length polymorphisms (RFLPs) targeting the 16S ribosomal RNA and the cytochrome c oxidase subunit I (COI) can be used to differentiate H. longicornis from the other Haemaphysalis species found in North America. Furthermore, we show that this RFLP assay can be applied to Haemaphysalis species endemic to other regions of the world for the rapid identification of damaged specimens. The work presented in this study can serve as the foundation for region specific PCR-RFLP keys for Haemaphysalis and other tick species and can be further applied to other morphometrically challenging taxa.

Background: Tick distributions have changed rapidly with changes in human activity, land-use patterns, climate, and wildlife distributions over the last few decades. Methods: To estimate potential distributions of ticks, we conducted a tick survey at 134 locations in western Kanto, Japan. We estimated the potential distributions of six tick species (Amblyomma testudinarium Koch, 1844; Haemaphysalis flava Neumann, 1897; Haemaphysalis kitaokai Hoogstraal, 1969; Haemaphysalis longicornis Neumann, 1901; Haemaphysalis megaspinosa Saito, 1969; and Ixodes ovatus Neumann, 1899) using MaxEnt modeling based on climate patterns, land-use patterns, and the distributions of five common wildlife species: sika deer (Cervus nippon Temminck, 1838), wild boar (Sus scrofa Linnaeus, 1758), raccoon (Procyon lotor Linnaeus, 1758), Japanese raccoon dog (Nyctereutes procyonoides Gray, 1834), and masked palm civet (Paguma larvata C.E.H. Smith, 1827)). Results: We collected 24,546 individuals of four genera and 16 tick species. Our models indicated that forest connectivity contributed to the distributions of six tick species and that raccoon distribution contributed to five tick species. Other than that, sika deer distribution contributed to H. kitaokai, and wild boar distribution, bamboo forest, and warm winter climate contributed specifically to A. testudinarium. Conclusions: Based on these results, the dispersal of some tick species toward residential areas and expanded distributions can be explained by the distribution of raccoons and by forest connectivity.

Since the raccoon (Procyon lotor) was introduced to Japan, studies have established that they are infested with native Japanese tick species. However, the quantity of ticks infesting raccoons is unknown. We conducted a survey of ticks on invasive raccoons captured on the Miura Peninsula, Kanagawa Prefecture, Japan, from April 2015 through June 2016 to determine the species of ticks and to quantify the intensity of tick infestation in order to obtain basal information related to the ecology of host-parasite relationships among indigenous tick species and an alien mammalian species. We collected and identified 15,931 ticks of two genera and six species, namely, Haemaphysalis flava, H. megaspinosa, H. longicornis, H. japonica, Ixodes ovatus, and I. tanuki, from 100 out of 115 raccoons. The dominant tick species was H. flava (96.8%) and individuals were mainly adults. Seasonal patterns of infestation intensity of adults and nymphs peaked in the autumn and winter and decreasing in the late spring and summer, May to August, while larvae peaked in August. Our results indicated that host-parasite relationships between invasive raccoons and Japanese tick species, especially H. flava, were established in Kanagawa Prefecture. The ticks infest invasive raccoons for their blood-meal and also for overwintering. The results of this study extend our understanding of the ecology of tick-borne diseases.

To examine outbreaks of mange in raccoon dogs (Nyctereutes procyonoides) with respect to population density, we analyzed camera trap videos, and isolated mites from raccoon dog carcasses. In a camera trapping survey, we categorized the skin condition of raccoon dogs, and used a number of independent videos to calculate the relative abundance index (RAI). The RAI of raccoon dogs with alopecia increased following an increase in the RAI of those without alopecia. Among 27 raccoon dog carcasses, 12 showed mange-compatible skin lesions. Sarcoptes scabiei was isolated from 11 of these raccoon dogs, indicating that sarcoptic mange was endemic in our study area. Therefore, a high relative population density may be a factor underlying epizootics of sarcoptic mange in raccoon dogs.

The effects of introduced mammal species on the ecology of parasites are often under investigated. The sika deeer, Cervus nippon, is host species of many hard ticks. We collected 8348 ticks on an island where sika deer were introduced. The most representative species was Haemaphysalis megaspinosa (n = 4198; 50.3%), followed by H. longicornis (n = 1945; 23.3%), H. cornigera (n = 1179; 14.1%), H. flava (n = 713; 8.5%), Ixodes turdus (n = 289; 3.7%), I. granulatus (n = 22; 0.3%), and H. hystricis (n = 2;< 0.1%) on an island where sika deer were introduced. H. megaspinosa and H. hystricis have not previously been recorded on the Izu islands. The high abundance of H. megaspinosa indicated that the tick species may have been introduced with the sika deer. Furthermore, H. megaspinosa larvae were more abundant at collection sites 21-40 days after sika deer were caught by foot snare traps indicate that engorged female of this tick species were forced to drop off in a very limited area near the foot snare trap. This represented a risk for hunters and people associated with wildlife control visiting the area.