Morphological development, distribution and ecology of the arctic oribatid mite Hermannia scabra (Acari: Oribatida: Hermanniidae) and synonymy of Hermannia gigantea.

Abstract

The topotypes (adult and juvenile instars) of the arctic oribatid mite Hermannia scabra (L. Koch, 1879) (Oribatida, Hermanniidae) from Vaygach Island (easternmost arctic Europe) were investigated and compared with those of Hermannia gigantea Sitnikova, 1975 collected from southwest Taymyr Peninsula, northern Middle Siberia, resulting in the following new taxonomic proposal: Hermannia scabra (L. Koch, 1879) (= Hermannia gigantea Sitnikova, 1975, syn. nov.). The morphology of its all instars is described and illustrated in detail on the base of specimens collected from the northern West Siberia (Shokalsky Island). The main morphological traits are summarized. Two northern species of Hermannia with granulate notogaster, namely H. scabra and H. nodosa Michael, 1988, were regularly mixed up in the literature. Their differential diagnosis is provided after elaboration of spacious materials. The morphological differences of juvenile instars of five species of Hermannia (H. gibba (C.L. Koch, 1839), H. jesti Travé, 1977, H. nodosa, H. reticulata Thörell, 1871, and H. scabra) are given. The biotopic preferences of arctic members of Hermannia are briefly observed.