Research on the mosquitoes of Angola - Systematic Catalog of ...

RIBEIRO, H. & R.,MOS, H, Cunha -- <strong>Research</strong> on the mosquitoes of Angola
ground water. Naturally occurring breeding places such as river margins
(26), ground pools at river edges (24) and permanent pools (7)
constitute the main breeding area of C. annulioris. Man-made irrigation
drains (19) and shallow earth wells (8) merely extended that main natural
breeding area. Lastly, the occurrence of annulioris in rock-pools (5) is
to be related to its (incipient?) ability to occupy the novel niches offered
by artificial containers in peridomestic habitat (4): two flower vases, a
drum and a discarded tin. Fig. 5 shows a small earth drain of turbid water
where C. annulioris bred.
In relation to this presumed trend to man-dependancy of annulioris
for breeding, it is also to be noted that the breeding water is often turbid,
dark and even foul water, apparently with a high organic matter content,
not infrequently clue to human activity (decaying , contamination
by human or cattle excreta, etc.).
In 10 out of the 89 ground water larval biotopes, abundant filament
tous green algae were recorded which, however, are not eaten by the
larvae. In 61 out of the 93 breeding places the pH of the breeding water
was measured, figures ranging from 4.8 to 7.0, with a mean of 5.8.
Associated mosquito larvae were only recorded in 69 out of the 93
breeding places of C. annulioris. Genera Anopheles (22 species) and
Culex (19) were the only mosquito genera significantly associated with
annulioris in its larval biotopes. In terms of species, the most frequent
associates were: An. coustani (24 times), C. tigripes (10), An. cydippis
and C. univittatus (9 times, each), An. rufipes rufipes (6), An. demeilloni,
An. funestus, An. rnaculipalpis, C. duttoni and C. salisburiensis (5, each)
and An. gambiae, An. marshalii, An. squarnosus, C. antennatus and
C. argenteopunctatus (4, each). All the other species were associated
occasionally, being found in less then 5 per cent of the above mentioned
69 breeding places.
In spite of being widespread and fairly common in Tropical Africa,
C. annulioris is known to be mainly a zoophilic mosquito, though it may
bite man rarely (35) (49) (43) (37). In Angola (Huambo), only two females
were caught as such by the writers, both at rest, at 7.30 a.m., one of
them in a hen-house and the other in a cow-house. All the other adult
specimens in collection were laboratory-reared.
Estud., Etas. c Dot'.- 134 69
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