Comparative Life History and Demographic Traits of Parthenogenetic and Bisexual Haemaphysalis longicornis in the Republic of Korea

ABSTRACT

The Asian longhorned tick, Haemaphysalis longicornis , is one of the predominant hard tick species in the Republic of Korea and an important vector of pathogens affecting both animals and humans, including severe fever with thrombocytopenia syndrome virus (SFTSV). H. longicornis occurs as both parthenogenetic and bisexual reproductive lineages that differ in geographic distribution and several biological characteristics. However, how differences in reproductive output, developmental timing, and stage‐specific survival collectively influence their demographic performance remains poorly understood. In this study, we compared morphology, body weight, blood‐feeding and post‐feeding developmental periods, stage‐specific survival, and reproductive output between parthenogenetic and bisexual lineages. Parthenogenetic females had larger idiosoma dimensions and attained heavier replete body weights than bisexual females. Parthenogenetic nymphs and adults completed blood feeding more rapidly, whereas larval pre‐molting, pre‐oviposition, and egg incubation periods were longer. Survival varied among developmental stages, with bisexual ticks showing higher survival during larval and adult reproductive transitions, including oviposition completion, whereas parthenogenetic ticks showed higher survival during the nymphal stage. Parthenogenetic females were estimated to produce more eggs than bisexual females (3,642 vs. 2,864 eggs per female), but cumulative stage‐transition survival was substantially lower (0.155 vs. 0.450). Consequently, the estimated daily demographic growth factors were broadly comparable between the parthenogenetic and bisexual lineages ( λ * = 1.0966 and 1.1054, respectively). These findings reveal that the higher reproductive output of parthenogenetic H. longicornis is counterbalanced by lower survival and longer development, highlighting contrasting life‐history trade‐offs rather than a simple demographic advantage of parthenogenesis.