Phoretic Mites Separated Spatially

A study on carrion beetles in central New York state, USA, has shown that the size of the forest and its fragmentation had a large impact on the load of phoretic mites (Gibbs and Stanton 2001). The diversity of phoretic mites for a single carrier species is often so high that the investigation of its phoretic mites might contribute a lot of high resolution site-specific information for a carcass. More detailed studies on the phoretic mite species Poecilochirus carabi associated with carrion beetles of the genus Nicrophorous showed that what was perceived as a single species were actually two different and therefore undescribed mites species (Brown and Wilson 1992). The difference, morphologically suggestive, became evident in crossing experiments between the mites phoretic on two sympatric carrion beetles, Nicrophorous orbicollis and N. tomentosus. Two sites in lower Michigan, USA, Kellogg Biological Station in Hickory Corners and University of Michigan Biological Station in Pellston are separated by 315 km from each other. At Hickory Corners, two different mite species exhibited strict host specificity for N. orbicollis and N. tomentosus. At Pellston, in contrast, P carabi was carried by N. tomentosus and N. defodiens, a species not found at Hickory Corners. A specialist mite species for N. defodiens could not be found at Pellston. Nicrophorus beetles reproduce on small carrion such as birds and mice. However, they are often found feeding on large carcasses such as humans, where they do not oviposit. During these feeding stops, Poecilochirus mites disembark to feed on the large carcass as well. Fascinatingly, most mites manage to return to their carrier before take off (Korn 1983). The phoretic mites of carrion beetles ovipositing on larger carcasses, e.g. Oiceoptoma species, have barely been described (Masan 1999).

0 0

Post a comment