Tyrophagus putrescentiae (Schrank) (Astigmata: Acaridae) as natural enemy for wood boring pest, Psiloptera fastuosa F. (Coleoptera: Buprestidae) in tropical tasar

In tasar silkworm culture the stem-boring jewel beetle Psiloptera fastuosa Fabr. (Buprestidae: Coleoptera) is considered as a major pest of tasar plant (Terminalia arjuna, Combretaceae) cultivation. The grubs of P. fastuosa often damage the Arjuna stem by causing dieback. Tyrophagus putrescentiae Schrank (Acari: Acaridae) infested buprestid eggs up to 15% and caused egg mortality up to 9%. The mite predation on the buprestid beetle is reported for the first time. The mite seeps the newly-laid egg-fluids causing the egg mortality suggesting that tasar plant stem-boring pest (P. fastuosa) can be partially controlled by the mite as a natural enemy.

Water mite predation on zooplankton of a tropical lake

Water mite (Krendowskia sp.) predation on zooplanktonic species from Lake Monte Alegre (São Paulo State, Brazil) was tested in laboratory experiments. One cladoceran, Daphnia gessneri, two copepods, Tropocyclops prasinus and Thermocyclops decipiens, and Chaoborus larvae III and IV were supplied as prey to adult mites. The cladoceran Ceriodaphnia cornuta was used in the experiment with mite nymphs. Only D.gessneri was preyed on by mites, at an average rate of 7 ind./mite/day, at 23-24ºC. Although Chaoborus was not eaten by the predator in the experiment, in direct observations older larvae were seen to be seized by several mites, both predators and prey sinking to the bottom of the vessel. Adult Daphnia was grabbed by its dorsal side, swimming together with the mite. There was an increase in predatory activity two hours after sunset.