Artengliederung und Verbreitung der Gattung Zetorchestes in Europa (Acari, Oribatida)

This paper gives a description of Zetorchestes grandjeani spec. nov.; it is identical with those animals which are called "l'espèce de Pise" by Grandjean (1951). Ζ. grandjeani differs from Ζ. flabrarius Grandjean, 1951 and from Z. falzonii Coggi, 1898 in showing a reduction of hairs in the posterior area of the notogaster, interlamellar hairs of medium length, only one pair of adanal hairs and a difference in the microsculpture of the cerotegument. This species moreover differs from Z. falzonii in the following characters: the presence of the notogastric hair c1, only slightly developed cuticula-wrinkles, and the nearly complete absence of these wrinkles in the anogenital region; there are two little indentations on the border of the rostrum. In contrast to Z. flabrarius the species Z. grandjeani has a slender sensillus and one hair on trochanter IV (table 1). Besides there is an intraspecific morphological variability in: body size, width of the sensillus-club, length of each lyrifissure on the notogaster, the number of the notogastric, genital and anal hairs, the shape of the fringe of the lamella on femur II, the diameter of the hairs pv', pv" and s on the tarsus of leg III, and also the diameter of the hair s on the tarsus of leg IV. Until now the new species has been found in Italy, France, Spain, Yugoslavia and Greece. Further finds of Z. flabrarius and of Z. falzonii are made known and the distribution of these species is discussed.