Biology Reference
In-Depth Information
of little vectorial importance. In the Korean Peninsula, on the other hand,
An. sinensis s.l.
shows a propensity for biting humans and has been identi-
fied as a primary vector (
Lee et al., 2001
). The larvae of
An. sinensis
complex
are associated with lowland, shallow, freshwater habitats. Adult females may
hibernate to overwinter from October to April when the temperatures drop
below 19 °C (
Chow, 1970
). Little is known regarding the biting habits of
An. superpictus
, particularly regarding host preference, but they are generally
considered to be exophagic. The larvae are commonly found in shallow,
flowing, fresh, sun-lit water. However, the species can adapt to human influ-
ences by using man-made pits and holes.
The primary DVS in the south-eastern part of Asia are the
An. dirus
and
An. minimus
complexes, both of which contain highly competent vector
species. Within the Dirus Complex, which contains seven sibling species,
again there is some variability in behaviours (depending on location and
sibling species) but the main vectors of the complex (
An. dirus s.s.
and
Anoph-
eles baimaii
) are both highly anthropophilic and will feed both indoors and
out. Biting activity appears highly sibling/species dependent with
Anopheles
scanloni
(a focal vector within the complex) biting at dusk,
An. dirus
biting
in the evening (between 2000 h and 2300 h) and
An. baimaii
biting as late as
0200 h. In general, outdoor resting both before and after feeding has been
reported for this species complex. The larvae of this complex inhabit small,
temporary, freshwater bodies and are therefore most abundant during the
rainy (monsoon) season.
Anopheles minimus s.l.
has three siblings, only two
of which (
An. minimus s.s.
and
Anopheles harrisoni
) are considered viable
contemporary vectors. Variability in reported behaviour may be a conse-
quence of misidentification or lack of differentiation between these two
species, although both are also considered opportunistic and plastic in their
behaviour.
Anopheles minimus s.s.
is potentially more anthropophilic, but also
adaptable depending on host availability. Overall,
An. harrisoni
is considered
more exophagic, exophilic and zoophilic than its sibling. Minimus Com-
plex larvae are typically associated with small- or moderate-sized streams
with slow, clear, cool and partially shaded water.
Anopheles minimus s.s.
has
been observed in a wider range of habitats from canopied forests to open
fields.
Anopheles harrisoni
, on the other hand, is more commonly associated
with agricultural areas. Further studies that utilise molecular assays to dif-
ferentiate sibling species are needed to understand the varied behaviour and
habitat preference of
An. minimus s.s.
and
An. harrisoni
.
It is clear that the behaviour of the Asian vectors is complicated, variable
and, as yet, not well understood. However, many of the species do exhibit
