Diversity of Hard Ticks (Acari: Ixodidae) Fauna on Green Habitats of Urban Areas in Eastern Croatia.

Hard ticks (Acari: Ixodidae) are vectors of numerous pathogenic microorganisms in humans and animals. In Croatia, very few studies have been conducted on the diversity of hard tick fauna in urban green areas. Therefore, the aim of this study was to investigate the diversity and seasonal dynamics of hard tick fauna in three eastern Croatian cities. Three species of ticks were recorded in Osijek and Vukovar, while six species were recorded in the area of the city of Vinkovci. In total, six species were collected during this study, and together with an earlier record of Ixodes canisuga, seven species are now known from urban green habitats in this region. The most abundant species was I. ricinus (82.06%), followed by R. sanguineus s.l. (9.03%), H. concinna (6.51%), D. reticulatus (1.26%), I. hexagonus (0.91%), D. marginatus (0.11%), and I. canisuga (0.11%). The detection of R. sanguineus s.l. in Vinkovci and Vukovar represents the first record of this species in eastern Croatia. In Osijek and Vinkovci, I. ricinus was the most abundant species. This tick is the primary vector of Lyme disease and tick-borne encephalitis, the two most common tick-borne diseases affecting humans in eastern Croatia. In Osijek and Vukovar, peak abundance of ticks was recorded in May, while in Vinkovci in March. Given that the species documented here represent 30.43% of all tick species recorded in Croatia, their presence in urban areas highlights the potential public health risk associated with ticks in these environments.