Biology Reference
In-Depth Information
lacking posterior cornua, and elongated palpi lacking a ventral spur. These are the
only males with a 2/2 dental formula in the entire genus Haemaphysalis. The vari-
ous spurs and spur-like angles of the body appendages (capitulum and legs) that
function as hair-hooking devices in so many other haemaphysalines are obsolete or
only very slightly developed in each Alloceraea stage. The unique leathery
Alloceraea integument is probably also specially adapted for water conservation.
3.8.2 Structurally Intermediate Haemaphysalis
The subgenus Herpetobia is supposed to be an intermediate between structurally
SP and SA haemaphysaline. The subgenus Herpetobia is a relict, pivotal branch in
Haemaphysalis phylogeny. All Herpetobia immatures and adults have an
SA-pattern rectangular basis capituli. Their palpi, however, which are compact, but
are slightly salient in certain nymphs, represent the forerunner of the broad palpi
characterizing SA haemaphysalines. The species included under SI group are H. sul-
cata, H. sundrai, H. kashmirensis,andH. himalaya.
3.8.3 Structurally Advanced Haemaphysalis
There are 29 species belonging to six subgenera included under this SA group.
The subgenera are Aborphysalis, Haemaphysalis, Kaiseriana, Rhipistoma,
Ornithophysalis, and Segalia. The basis capituli of both immatures and adults in
this group is rectangular and usually bears posterior cornua. The palpi of immatures
and adults mostly show some basal broadening of segment II; some retain a com-
pact form. The salience begins with a slight extension of the posterior breadth and
reaches the broadly triangular outline characterizing most species of this genus.
The dental formula is 2/2 in immatures and 4/4 in adults, rarely 3/3 or 4/4 in the
former, and occasionally 3/3 or 5/5 to 7/7 in the latter. Adults vary in length
between 2.2 and 3.5 mm; a few are even smaller; but very few exceed 3.5 mm.
Most of the species occur in humid, wooded zones. In the subgenus Kaiseriana
adults are structurally specialized, some extremely, for parasitizing Artiodactyla;
most of the adults feed on Carnivora, but other hosts are exceptional. Immatures
parasitize small mammals, especially Rodentia, and those of a few species feed on
Artiodactyla and Carnivora as well as Rodentia. The hallmark of Kaiseriana is a
hair-hooking spur extending from the posterodorsal margin of the adult palpal seg-
ment III. In cornigera group males this spur is supplemented or replaced by a gap
in the external surface of the palpus. The generally small, often frail cornigera
group adults have moderately to very large cornua on the basis capituli, an extraor-
dinary variety of hair-hooking devices on the greatly broadened palpi, and pro-
nounced spurs on most or all coxae. The coxa IV spur is lanceolate in spinigera;
double (scissor like) in anomala, cornigera, and shimoga.
The subgenus Rhipistoma, probably the most recent of haemaphysaline subge-
nera, in contrast to Ornithophysalis, is one of the earliest types of SA haemaphysa-
line. The subgenus Haemaphysalis apparently evolved from Herpetobia (or a
related, now extinct ancestor) in the Indian subregion of the Oriental region and
