An Improved Laboratory Larval Medium For Culicoides Guttipennis (Coq.) (Diptera: Ceratopogonidae)1

Abstract

Comparisons of larval survival and adult emergence from several experimental media were made to develop an improved larval medium for colonized Culicoides guttipennis (Coq.). It was verified that microorganisms were an important food source for the larvae. Comparisons were made of sterilized and nonsterilized decaying leaf matter normally used in the larval diet. No larvae developed beyond the 1st instar in the sterilized medium, but adults emerged from the nonsterilized leaf matter. Various microorganism cultures and media were screened. A simple hay infusion medium inoculated with weekly-collected stump-hole microorganisms was found to be the most satisfactory diet. The incorporation of a vermiculite substrate into the medium improved the larval environment, resulting in increased numbers of emerging adults.