[Ultrastructure of the epithelium of the midgut in nymphs of Hyalomma asiaticum (Acarina, Ixodidae) ticks during feeding].

The midgut epithelium of H. asiaticum nymphs was studied by means of electron microscopy. It has been shown that during feeding the midgut epithelium of the above nymphs consists of three types of cells: reserve, secretory and digestive ones. There have been revealed two types of the digestive cells. The cells of the first type are capable for two forms of blood endocytosis: phagocytosis and pinocytosis. During feeding in these cells takes place fast intracellular digestion. This type of cells dominates at the beginning of feeding. The second type of digestive cells prevailing at the end of feeding is represented by specialized cells consuming only haemoglobin. A certain part of these cells preserves for a long time an intracellular reserve of haemoglobin.