Effect of temperature and antibiotics on the hatching of Microxeromagna armillata (Mollusca : Hygromiidae) eggs: developing an in vitro bioassay for fungal egg parasites

Abstract

Eggs of Microxeromagna armillata were incubated on water agar at different temperatures (5–40°C) and with each of three antibiotics (chloramphenicol, neomycin and streptomycin) at a range of concentrations (50–500 mg L^–1), to optimise conditions for a bioassay for egg parasites. Hatching of M. armillata progressed unimpaired over a wide temperature range (8–30°C). Delayed hatching occurred at 5°C and eggs died at temperatures of 37°C and above. Streptomycin had the least effect on hatching, with M. armillata tolerating concentrations up to 250 mg L^–1. Chloramphenicol and neomycin were inhibitory, even at concentrations of 50 mg L^–1.