Culex ( Culex ) iyengari n. sp., a New Species of Mosquito 
(Diptera, Culicidae) from the South Pacific 
P. F. Mattingly and J. Rageau 1 2 
This is a member of the Culex pipiens series of 
Edwards (1932:208) and of a rather well- 
defined subgroup of that series which may be 
termed the Culex trifilatus subgroup. The 
species included in this subgroup share with 
Culex pipiens the strongly bent ventral arm of 
the male phallosome (Fig. Iv.a.) but differ 
from it in the more strongly developed outer 
division of the dorsal arm, which is here 
termed the basal arm (Fig. lb. a.), and in hav- 
ing the tip of the inner division of the dorsal 
arm characteristically modified (Fig. Id. a.). 
This last modification is, however, less strong- 
ly marked in the Pacific species, other than 
C. pervigilans , than in those found elsewhere. 
C. pacificus (Fig. lb) is remarkable in exhibit- 
ing spicules on the ventral arm of the phallo- 
some which are reminiscent of some of the 
banded-legged members of subgenus Culex. 
In addition to C. iyengari the group includes 
C. pervigilans Bergroth from New Zealand, 
C. pacificus Edwards from New Hebrides, C. 
trifilatus Edwards from East and South Africa 
and the Cameroons, C. tamsi Edwards from 
the island of Sao Thome in the Gulf of Guinea, 
the northern Palaearctic C. torrentium Martini, 
and the eastern Palaearctic C. vagans Wiede- 
mann. It thus furnishes a good example of a 
Palaearctic group having a southward exten- 
sion down the East African highlands into 
South Africa and another, further east, into 
the Australasian region. It is entirely absent 
1 British Museum (Natural History), London, and 
Institut Francaise d’Oceanie, Noumea, New Caledonia, 
respectively. Manuscript received January 7, 1957. 
2 Since this paper was finished Dr. E. N. Marks has 
informed us that the undescribed male of the banded- 
legged Culex {Culex) miraculosus Bonne-Wepster (1937) 
from New Guinea also has a phallosome of the C. 
trifilatus type. We are most grateful to her for this 
interesting piece of information. 
from the intervening Oriental region except 
for some penetration into the northwest cor- 
ner by C. vagans (Barraud, 1934: 418). The oc- 
currence of members of the group in the Came- 
roons and in the Gulf Islands exemplifies the 
East African element in the Cameroons fauna 
which is a familiar feature of many groups. 
The occurrence of another member so far 
south as New Zealand is interesting and there 
has been an implied suggestion that this is 
an introduced species. Thus Edwards (1932: 
210) tentatively suggested placing the Palae- 
arctic C. torrentium in the synonymy of the 
New Zealand C. pervigilans. The idea is given 
some plausibility by the history of whaling in 
the New Zealand area during the nineteenth 
century. A careful examination shows, how- 
ever, that C. pervigilans (Fig. 2c) lacks two of 
the small modified setae on the subapical lobe 
of the coxite which are present in C. torrentium 
as in C. iyengari and C. pipiens (Fig. 2a, d). The 
style of C. torrentium is also distinctly nar- 
rower than that of the New Zealand species 
and it seems best to maintain them as distinct 
species, especially as the early stages of C. 
pervigilans are not available and have only 
been inadequately described (Graham, 1929: 
221). 
C. torrentium breeds readily in barrels and 
metal tanks and thus certainly gives the im- 
pression of a species susceptible to human 
introduction. There is some reason to believe 
that it may have been introduced into Great 
Britain in recent years (Mattingly, 1951: 172). 
It has previously been thought of as an ex- 
clusively northern species but it has recently 
been found as far south as Devonshire and 
Dorset (Lever, 1954: 65) and the French Py- 
renees (Sicart, 1954: 228). 
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