On the status of Morphologically divergent tick populations of Amblyomma triguttatum Koch (Acarina: Ixodidae).

Abstract

In a study of ticks determined as Amblyomma triguttatum Koch, 1844 on the descriptions of Koch (1844, 1847), Neumann (1899), and Robinson (1926), four distinct morphological forms could be recognized among the females. The males associated with the females of one form could be distinguished by the ornamentation pattern, but no character was found to separate the males of the other forms. The available evidence is considered to favour a subspecific rather than a specific status for each form. However, as no substantial evidence was obtained of the presence of intermediates in the zones of contact between forms, a change of rank may be required when further material becomes available or cross-breeding is undertaken. The subspecies have been named A. t. triguttatum Koch, A. t. ornatissimum, subsp. nov., A. t. queenslandensis, subsp. nov., and A. t. rosei, subsp. nov. The morphological differences between these subspecies are discussed and their geographical and host ranges are recorded.