ORIBATIDA OF CANADIAN PEATLANDS

This paper reviews and summarizes preliminary data on the taxonomy, distribution, and ecology of oribatid mites of Canadian peatlands, primarily those of eastern Canada. This fauna is a heterogenous assemblage comprising 71 species in 49 genera and 34 families, found in four main types of habitats: aquatic, mesic, xeric, and epigeal. About half of the oribatid fauna of peatlands, and most aquatic species, are restricted in distribution to the Nearctic. Oribatid taxa known or suspected to be parthenogenetic are much better represented in peatlands than in the general Canadian fauna. Data on the feeding habits of odonate larvae in Newfoundland bog pools, based on gut content analysis, show that oribatid mites, in particular species of Limnozetes Hull and Hydrozetes Berlese, are common prey of species of Aeshna Fabricius, Leucorrhina Brittinger, and Libellula L. A synopsis of available data suggests that assemblages of Limnozetes species may be useful in characterizing peatlands.