Published online by Cambridge University Press: 10 July 2009
Since Mr. F. W. Edwards' “Revised Keys to the known larvae of African Culicinae” appeared (Bull. Ent. Res. iii, pp. 373–385) the larvae of several additional species—all belonging to the tribe Culicini—have been found in the Gold Coast Colony. These larvae, collected at Accra and at Sunyani in Ashanti, are briefly described here and their position in Mr. Edwards' keys indicated so far as possible.
* The number is variable even on the two sides of the same larva ; one specimen had three on one side and seven on the other.—F. W. E.
* The adults which. Dr. Ingram sent as having been reared from this remarkable larva were C. pruina, but the larvae are totally different from those attributed to that species by Dr. W. M. Graham and described by Wesché under the name of C. pallidothoracis, Theo. (Bull. Ent. Res. i, p. 36). Dr. Ingrain also obtained specimens of this latter form (see fig. 7), which he associated with adults of C. guiarti, Bl., though this larva is different from that assigned to C. guiarti by Graham. It remains for future investigators to decide which of these two is the true larva of C. pruina.—F. W. E.
* In my paper on African Mosquito Larvae (Bull. Ent. Res. iii, p. 378) I briefly noted a larva which had been received as that of Stegomyia sugens or Uranotaenia nigripes, and appeared peculiar in having a lateral chitinous plate in addition to the comb on the eighth segment. Mr. Knab shortly afterwards wrote suggesting that this larva might be a Uranotaenia, as the possession of a cMtinous plate with the comb at the edge was one of the characters of the genus, a fact of which I was not then aware. Dr. Ingram's interesting discovery of the larva of U. annulata proves that the Sierra Leone larva must indeed be that of U. nigripes, as the two are very similar and agree in having rounded heads and slender frontal hairs. The chief points of difference between U. nigripes and U. annulata are as follows : the two anterior pairs of frontal hairs are placed far forward, the outer three branched, the inner simple and much closer together than in U. annulata ; the comb-teeth are about 14 in number and sharply pointed ; the siphon is narrower towards the tip ; and the anal papillae are nearly three times the length of the anal segment.
It is interesting to note that the group Pseudoficalbia, to which both these species belong, can apparently be defined on the characters of the larval head as well as on the scale characters of the adults.—F. W. Edwards.