Autogeny and polymorphism for wing length in Leptoconops becquaerti (Kieff)

Data given show that in Jamaica, Leptoconops becquaerti is polymorohic for wing length in both sexes. The polymorphism is associated with autogeny so that in a given population the smaller ** are autogenous, the larger anautogenous. The autogenous ** emerge from the pupa with ovaries already in early Stage IV of development; at 26.6 C egg maturation is completed within 24-36 hr post-emergence. The number of eggs produced autogenously in the 1st genotrophic cycle is comparable with that seen in anautogenous ** fully engorged with blood and kept under optimum conditions. Larval environment does not appear to affect the expression of autogeny by regulating the proportion of ** that produce eggs without taking blood. Instead, it appears that wing length polymorphism and autogeny are entirely under genetic control. Some observations on mating and resting behaviour in the field are described. Reasons are given for believing that human discomfort is caused almost entirely by anautogenous * L. becquaerti. (AU)

Sandfly research unit in Montego Bay, Jamaica

Prior to 1960 the main biting nuisance in the Montego Bay area was caused by the swamp sandflies culicoides furens and culicoides barboai. Filling the swamps with sand, whilst eliminating these two species, encouraged the development of a hitherto little-known species (leptoconops bequaerti) whose nuisance value soon exceed that of the original species. The discovery of the breeding sites of this sandfly in 1962 enabled its distribution to be studied and treatment with insecticide started. The limited nature of the breeding grounds shows good prospects for environmental control in the future (AU)