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

RIBEIRO, H. & RAMOS, H. Cunha -- <strong>Research</strong> on the mosquitoes of Angola -- X
rock-pools. Ground water biotopes included ground pools (31), river margins
(14), irrigation drains (7), shallow earth-wells (6), pools in river beds
(4), a pond and a crabhole. Artificial containers were represented by old
rubber tyres (10), barrels (8), cement water-tanks (8) and drums (2). The
nature of the breeding area of C. tigripes as shown by these data, points
to an appreciable man-dependance of this species for breending.
The breeding water was either limpid or turbid, sometimes even foul
water with decaying vegetables (, sisal, fallen leaves, etc.).
Living macroscopic aquatic vegetation was either present, sometimes
even abundant, or completely absent. !n seYeral instances, the presence
of filamentous algae was recorded. The pH of the breeding water measured
in 50 different breending places, ranged from 5.0 to 8.0, though it
became evident that C. tigripes shows a marked preference for acid
waters, these representing 88 per cent of the total. The salt content
(NaCl) of the water, deterre:reed in 16 biotopes, ranged from 0.1 to
4.15 g/1 (mean 1.1 g/l), salinity being an important limiting factor for
breeding of tigripes.
Larvae of C. tigripes are voracious predators on other mosquito
larvae and we observed a full grown tigripes larva devoring three third
or fourth instar larvae of C. pipiens at intervals of about 15 minutes.
It seems that, in fact, the presence of prey mosquito larvae is a decisive
factor for breeding of tigripes.
As to the associated mosquitoes, larvae of other species of Culex were
present in 75 out of the 104 breeding places of tigripes, while Anopheles
spp. occurred in 37 of these, Uranotaenia spp. in 10, Aedes spp. in 6,
Ficalbia (F. mimomyial'ormis) in 3, and Aedomyia (Aed. [ur/urea) in
only one. 52 species of associated mosquitoes were recorded from the
Angolan larval biotopes of tigripes, belonging to genera Culex (22 species),
Anopheles (19), Aedes (5), Uranotaenia (4), Ficalbia (1) and Aedemyia
(1). The species most frequently associated with larval tigripes were,
by decreasing order of frequency: C. duttoni and C. univittatus (each
one recorded from 20 larval biotopes), An. coustani (18), C. p. piplens
(11), C. p. quinque/asciatus and C. decens (9), An. gambiae (7), An. demeilloni,
An. maculipalpis, C. annulioris, C. simpsoni and U. fusca (6),
An. pharoensis, C antennatus and C. telesilla (5), An. cydippis, An. rhodesiensis,
C. ethiopicus and C. poicilipes (4) and Ae. yangambiensis, An.
r. rufipes, C. chorleyi, C. cinerellus, C. invidiosus, C. theileri and F. mimomyiaformis
(3).
Estud., Errs. e Doc.- 134 53