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

RIBEIRO, H. & RAMOS, H. Cunha -- <strong>Research</strong> on the mosquitoes of Angola X
between African specimens and those from Western India (83) (24) (84)
(82). In Angola, also 4 out of the 5 known localities for C. tritaeniorhyn-
chus are coastal (Map 10). In that concerns the morphology of the
Angolan specimens (both adults and larvae), no significant disa-
greements could also be found between our material (including male
terrainalia) and known descriptions concerning the type form, namely
the more recent redescription by R. Reuben (84). The only exception
to be noted (though certainly not significant, given the usual variability
of this character) is the reduction of the anal papillae in Angolan lar-
vae (particulary in those from Barra do Cuanza and Novo Redondo)
which are only - length of saddle, much as described by Kirkpa-
trick in Egypt (op. cit.). In the male terrainalia, the appendages of
the apical lobe of coxite (not mentioned in Reuben's redescription) are
as described by Ovazza et al. (81), from Ethiopian males.
For distinguishing between C. tritaeniorhynchus and its closely
allied C. thalassius, see characters used in the diagnostic keys under 6.
In the female tritaeniorhynchus, the proboscis is usually mostly pale
(either beneath and on the upper side) for about the basal two thirds.
BIOEOOLOGICAL NOTES. The following 8 breeding places of the
ground breeder C. tritaeniorhynchus were recorded, all of them well
exposed to sunlight: 4 borrow-pits, 2 shallow earthwells and the margins
of 2 marshy pools. The breeding water was often turbid with pH (six
biotopes examined) of 7.0 (4 times), 6.7 and 10.0. The chloride content
(NaCl) of the breeding water, measured in six biotopes, ranged from
0.5 to 19.4 (mean 5.5) g/l, thus showing the preference of tritaeniorhynchus
for salt water breeding.
This ability of the Angolan population of C. tritaeniorhynchus
for breeding in salt water seems to be related, on the one hand, to the
above cited reduction of the anal papillae of larvae and, on the other
hand, to be also reflected in the larval associations of this mosquito.
The following are the associated species recorded: Culex thalassius and
Anopheles listeri (4 times each), C. p. piplens (3), An. azevedoi, An.
ziemanni, C. antennatus and C. univittatus (twice), and Aedes durbahensis
angolae. Ae. natronius, An. gambiae, C. p. quinque/asciatus
and C. simpsoni form A (once), five of which are well-known halophilic
species. It is also perhaps worth to note the frequency of the
association of the introduced C. tritaeniorhynchus with the autochtho-
Estud., Ens. e Doc.- 134 115