Comprehensive DescriptionRead full entry
Biology of the Bee Mite Genus HorstiellaSpecies of Horstiella are exclusively associated with the ground nesting bee genus Epicharis in the Neotropics. The mites occur on the subgenera Triepicharis, Pareipcharis, Hoplepicharis, Epicharis (s.str.), and Epicharana, while the subgenera Epicharoides and Epicharitides lack these mites. The association of Horstiella and Epicharis is quite unusual in that most species of Epicharis harbor two species of Horstiella, a condition known as synhospitaly (Ochoa and OConnor, 2000). The mite species pairs were almost always spatially segregated on an individual host. No host specificity was detected, suggesting that this association is shaped after the initial diversification of the genus Epicharis (Ochoa and OConnor, 2000).
Most of Horstiella species are commonly found on the bee's propodeum, while Horstiella megamyzidos specifically attaches under the lateral edges of the metasomal tergites and under the sternites. In male bees, the more frequent attachment of mites to the ventral region of the mesosoma and metasoma correlates with the mating position of the host bees. Because only the female bee makes nests, mites developing in a cell with a male bee would normally have no opportunity to found new colonies. Migrating to the ventral surface of male bees would, therefore, give the mites a selective advantage because this can facilitate transfer onto the body of a female bee during copulation, which occurs with the male above the female (Ochoa and OConnor, 2000).
Phylogeny of Horstiella, Medeus, and Horstia based on morphology was presented by Ochoa and OConnor (2000).