Haemaphysalis (Garnhamphysalis) mjoebergi: identity, structural variation and biosystematic implications, deer hosts, and distribution in Borneo and Sumatra (Ixodoidea: Ixodidae).

Haemaphysalis (Garnhamphysalis) mjoebergi Warburton was reported from four male specimens from Sarawak, Borneo. We redescribe herein the male, from three specimens from Sarawak and 24 from Lampung District, Sumatra, and describe the female from 24 specimens from Lampung. Male structural variation in the dental formula and development of the coxa IV spur and segments of legs III and IV is unusual or unique in the genus Haemaphysalis. "Atypical" males might easily be misidentified. This species provides an ideal model for experimental study of population genetics and evolutionary processes and of biological factors influencing body size and structural variation in the genus Haemaphysalis. The sambar deer, Cervus unicolor brookei Hose (Sarawak) and C. unicolor equinus Cuvier (Sumatra), appears to be the chief host in humid, marshy, lowland forests and secondary growth. Single collections were from a human and a domestic cow. The dynamics and vector potential of this tick should be investigated in environments being exploited for human settlement and cattle breeding.