Hybridization experiments using 3 species of the scrub typhus vectors, Leptotrombidium akamushi, L. deliense and L. fletcheri

Abstract

Leptotrombidium akamushi (♀) and L. deliense (♂) produced the F_1 generation (F_<1ad>), from which the F_2 generation (F_<2ad>) was successfully obtained. This indicates a close genetical relationship between the two species. L. akamushi (♀) and L. fletcheri (♂) also produced the hybrids (F_<1af>), but no F_2 eggs were obtained. Hybridization between L. deliense and L. fletcheri was not successful, indicating their independency as species. The arrangement of setae was observed and standard scutal measurements were taken in these 3 species and the hybrids. The hybrids showed the same setal arrangement as their parents in F_<1ad> and F_<2ad>, or an intermediate pattern in F_<1af>. The scutal measurements showed that the F_<1ad> shared characteristics of the parents and that F_<1af> and F_<2ad> were very similar to L. deliense.