Age Composition Of A Natural Population Of Anopheles Quadrimaculatus Say (Diptera: Culicidae) In Maryland, U. S. A.1

Abstract

The age composition of a natural population of ANOPHELES QUADRIMACULATUS was determined at the Patuxent Wildlife Research Center, Maryland. This was a 20-month study, from July 1963 to March 1965, during which 9473 A. quadrimaculatus ♀♀ were collected for dissection. Six seasonal broods of gonoactive ♀♀ were produced from early May to mid-September. A new age group called “post teneral” is described; this is a gonoinactive category between the teneral and gonoactive nulliparous age groups. An increase in the proportion of inseminated post teneral females during late summer indicated the onset of overwintering a month before full fat bodies were first observed. It was found that a blood meal was not taken prior to overwintering. Gonotrophic dissociation was only observed in 4 individuals during the study. Mortality between succeeding gonoactive age groups varied from 40–50%, which suggests a daily mortality rate of about 10%.