Notes on the species of the genus Schwiebea described by Oudemans (Acarina, Astigmata)

INTRODUCTION Oudemans (1916) has erected the genus Schwiebea, for the reception of a single species, S. talpa. Since that time more than thirty species have been described in or transferred to this genus. Some of these species have been poorly described or are known only from the hypopial nymph and, therefore, their exact taxonomic position remains uncertain. Beside the typical species, Oudemans (1924a, b) has described two other species in the genus Schwiebea: S. scalops and S. italica. Moreover, two other species described by Oudemans in the genus Tyroglyphus have been transferred to Schwiebea by some authors: T. novus Oudemans, 1906, and T. eurynympha Oudemans, 1911. The purpose of this paper is to redescribe these five species of Oudemans and by this way to contribute to a better knowledge of these species as well as of the genus Schwiebea. The description and drawings that are published were made after the typical material in the Rijksmuseum of Leiden. REMARKS ON SOME ORGANS OF THE HYPOPI OF ACARIDAE We here use the nomenclature proposed by us for certain organs of the hypopi. We have replaced the term "gnathosoma" by the term "palposoma" (see Fain, 1968 and 1972). This organ is a cuticular projection bearing two solenidia and one or two pairs of simple hairs. It is not homologous of a gnathosoma but only a sensory organ. We think therefore that the term palposoma is more appropriate than the old term gnathosoma used so far. We have created the new term "conoid" (= in french "conoïdes") for the two pairs of modified hairs situated in the posterior and lateral regions of the suctorial plate and also for the modified hairs present in some genera