Comprehensive DescriptionRead full entry
Biology of the Bee Mite Species Locustacarus buchneriLocustacarus buchneri is an internal parasite of bumblebees occurring in tracheae and air sacs. Husband and Sinha (1970) reconstructed its life cycle. In the late April, the queen of Bombus bimaculatus emerges from overwintering sites in the soil. Within a few days, female mites in the tracheae enlarge as the haemolymph is ingested and ovaries begin to function. Several female mites may be found in tracheae of each queen bee. Nearly one week after emergence of a queen bee, eggs hatch. As many as 50 eggs were associated with a single female mite. Paired male and larviform female mites may be found among the eggs. In some cases the sex ratio of young mites is near unity. Some females may have been unfertilized and may produce only males. Males have poorly developed mouthparts, are short lived, and do not leave the host bee. Larviform female mites migrate to the tracheae of worker bees, attach to the tracheal walls, molt, and begin to enlarge. Adult females with only two legs and a greatly distended body cannot leave the host. This cycle may be repeated several times during the next eight weeks. In the first week in July, male bees and new queen bees emerge. Males of Psithyrus spp., B. vagans, and other B. bimaculatus occasionally enter the nest and may bring in or take out larviform female mites in the tracheae. By early August, new queen bees have mated, left the nest, and some may have entered diapause at sites several inches below the ground. After the new queen bees leave the nest, few new workers are produced and older workers accumulate more and more mites. The numbers of mites in worker and male bees in August is sufficient to severely injure the bees. Diarrhea is observed and some bees are lethargic and no longer forage. It was at this time that a small male mite was found. This observation is slight evidence that small males may be produced by crowding of mites, poor nutrition, or by aging of the parent. Because worker bees, male bees, and the old queen bee die during fall, the only mites which survive to the following April are in the tracheae of young queens in diapause.