Growth of Ornidia obesa (Diptera: Syrphidae) Larvae on decomposing coffee pulp

Abstract

Newly-hatched larvae of the green hover fly Ornidia obesa (Diptera: Syrphidae) were allowed to grow on coffee pulp that had started to decompose for two days and taken from the anaerobic portion of a heap. This substrate was maintained in Petri dishes at room conditions (25 ± 5°C, 43·0 ± 12.9% air relative humidity) so as to obtain a better understanding about the larval growth of the above species on coffee pulp. A sigmoid model indicated that the maximum larval growth rate was 16·8 mg (wet basis) day⁻¹ at 13·9 days after hatching, that the period of most rapid growth was 10·0–18·9 days and that the larvae reached almost their full development 25 days after they emerged from eggs. It was also found that a comparatively slight decrease of substrate moisture caused a lowering of larval weight.