Observations on the feeding and life history of the mite Nothrus biciliatus (Koch)

The mite Nothrus biciliatus (Koch) (Acari: Cryptostigmata), obtained in large numbers from a coffee grove in Rehovot, Israel, was studied under controlled laboratory conditions. Young cultures of diverse fungi were generally more attractive to the mite than older ones, Ascochyta sonchi being the over-all favourite. Duration of development at 28°C was very variable, lasting from a minimum of about 3 months when fed on baker's yeast to a maximum of 9 months when offered coffee leaves or mycelium of A. sonchi. The mites deposited an average of 27 eggs per female, reproduction being thelytokous. When offered a diet composed of A. sonchi and coffee leaves, the mites deposited a mean of 17.9 eggs, as compared to 10.8 when fed on the fungus alone. The amount of baker's yeast consumed per mite was estimated to be 6.5-6.8 mg (live weight) per day. Measurements of faecal pellets of N. biciliatus and of various body parameters revealed a close correlation between the former and the latter. The mite skeletonizes fallen coffee leaves both in the grove and in the laboratory.