fanned southeastward into the Oriental region and northeastward into the Palearctic
region. Wild and domestic Artiodactyla (various deer, wild pigs, serow, goral,
blackbuck, etc.) are the chief hosts of most adults of the subgenus Haemaphysalis.
Carnivora are secondary hosts of some of these 11 species.
In Aborphysalis palpi differ from those of most haemaphysalines except Segalia
is being broadly expanded either in larvae and nymphs or only in nymphs, and
compact or campanulate in adults. All capitular spurs (cornua and palpal segment
III ventral spur) are much reduced, and no other hair-hooking devices except the
leg spurs are present on these ticks. The capitulum does not function for hair hook-
ing, but the leg segments may do so with their sundry spurs, none of which are
large. The reversal of the usual immature-adult palpal form in Aborphysalis is pos-
tulated to be a functional adaptation for coexistence with spiny and quilled
Rhipistoma is probably the most recent haemaphysaline subgeneric assemblage.
It shows signs of contemporary speciating associated with small- and medium-sized
Carnivora in the Oriental, Ethiopian, and Malagasy regions. Only two species are
found in India under this subgenus. All Rhipistoma immature-stage and adult palpi
are broadly expanded posteriorly; spurs or grooves as hair-hooking devices modify
many. The basis capituli has small to large cornua. The capitulum (basis capituli
and palpi), assists Rhipistoma movement among the host pelage. Coxal and tro-
chantal spurs are unspecialized, generally small, or even obsolete.
3.9 Tick-Borne Diseases in India 48,87,94,95,106,123
Other tick-borne maladies
Haemaphysalis ticks are efficient vectors of a number of protozoan, viral, rick-
ettsial, and bacterial diseases of man and domestic animals. The immature stages
of these ticks often feed on rodents, lagomorphs, birds, etc., which are resources of
some of these disease-causing pathogens. The pathogens may be transmitted to
man and domestic animals when the immature stages of these ticks feed on
them. 3,48,95 A brief review of tick-borne diseases is given below.
Theileriosis and babesiosis are two common important protozoan diseases,
affecting cattle population in India. Theileria annulata is the agent causing theiler-
iosis in many countries including India. The vectors of T. annulata are various spe-
cies and Hyalomma, which have been summarized by Geevarghese and Dhanda.
The common protozoan parasite causing babesiosis in India is Babesia bigemina.