2.5 Structurally Advanced Haemaphysalines
There are 11 subgenera under this category constituting approximately 132 species
In this group, the basis capitulum is rectangular without any lateral expansion in
both immatures and adults and usually bears posterior cornua.
The palpi of immatures and adults mostly show some basal broadening of
segment II, and some retain compact form. The salience begins with the slight
extension of the posterior breadth and reaches the broadly triangular outline charac-
terizing most species of this genus. The dental formula of immatures is 2/2, rarely
3/3 or 4/4, and in adults 4/4, rarely 3/3 or 5/5 to 7/7.
No SA populations occur above 1,500 m altitude in the Himalayas or elsewhere.
Host-adapted structures are pronounced in this group, more in males than in
females. These adaptations are less pronounced in nymphs and even less in larvae
as these can slip between the host hairs and do not have to fight their way.
2.5.1 Subgenus Ornithophysalis
Ornithophysalis, with its broad palpi, appears to have evolved abruptly from SP
subgenera with compact palpi when birds and mammals replaced reptiles as the
world's dominant vertebrates. Significantly, of the twenty contemporary
Ornithophysalis species, six parasitize only birds, five parasitize both birds and var-
ious mammals, three parasitize birds and marsupials or only marsupials, and two
parasitize Oriental or Australian rodents. In India only five species have been
recorded belonging to this subgenus.
Keys to Identify Species of Subgenus Ornithophysalis
1. Basolateral margin of palpal segment II is convex or rounded...................
Salience is sharp and ventrally bearing a prominent projection laterally...................
2. Ventral spur of palpal segment III is elongately triangular, overlapping anterior half of
palpal segment II; spurs of coxa I and trochanter I are large, having sharply pointed apex;
infrainternal setae are long, lanceolate, and number 4...................[H. ornithophila]