The nutritive region in the ovaries of astigmatic mites (Acari: Acaridida)

Abstract

The astigmatic ovary consists of a nutritive region surrounded by maturing germ cells. Serial semithinsections and computer-generated 3-D-reconstructions were used to analyse the ovaries of four different astigmatic species (two free living mites, Sancassania berlesei and Glycyphagus domesticus as well as two parasitic ones, Otodectes cynotis and Chorioptes bovis). The nutritive region is always restricted to one end of the ovary: it lies anteriorly in the parasitic species and posteriorly in the free-living species. In one specimen of G. domesticus, one ovary had two nutritive regions. The nutritive regions possess only a single nucleus with evenly distributed nucleoli. The nucleus is composed of several multiply interconnected strands. Altogether, the nutritive region and the general architecture of astigmatic ovaries closely resemble telotrophic meroistic ovaries of insects.