[Ultrafine structure of the intestinal region of hungry nymphs of Ornithodoros papillipes (Acarina, Argasidae)].

Studies were carried out of the ultrafine structure of the midgut epithelium of hungry nymphs of O. papillipes. The intestinal epithelium has been shown to consist of both reserve and digestive cells which are at different stages of blood digestion. The former are characterized by a poor development of surface structures and by the absence of inclusions. On the contrary, the digestive cells abound in inclusions most of which are associated with intracellular blood digestion. On the surface of such cells there are specialized pinocytosis structures: coated kesicles and tubular invaginations. A number of cells possess vacuoles which are, apparently, secretory in their nature.