"Nymphes plissées" structure of the cuticle of juveniles of some oribatid mites (Acari: Oribatida)

Abstract

The cuticular structure of juveniles of several oribatids of different families with wrinkled cuticles were compared: Hermannia gibba, Tectocepheus velatus, Scutovertex minutus, Achipteria coleoptrata and Eupelops occultus. Both the surface and internal structures of the "plissée" were studied. Light microscopy revealed several patterns in mites studied with Masson's triple stain and these results were supported by TEM. Although the "plissée" looks similar at the body surface, the structure and ultrastructure differ among groups. Some types of wrinkling is supported by small muscles, probably for changing body shape. Differences in the structure of the cuticle of the prosoma and opisthosoma were observed. The differences in the wrinkling in the cuticle in diferent lines is associated with change in the body shape in response to different moisture conditions.