The structure of the female sand fly (Phlebotomus papatasi) alimentary canal

In the sand fly vector, Leishmania parasites. are confined to the alimentary canal. During much of their development, promastigotes are attached to the watt of the gut via their flagella. In this context, the surface of the different regions of the sand fly alimentary tract lumen warrants scientific attention. In this paper, the various regions are described, for the first time using scanning electron microscopy. The cibarium and the pharynx, which function as pumping organs, are lined with cuticle. Parts of the cibarium and the pharynx bear different types of cuticular spines and appendages. The midgut is lined with microvillar epithelium, which secretes the peritrophic matrix following a blood meat. The wider proximal part of the hindgut pytorus) is lined with transverse cuticular ridges with tentacle-like appendages. Leishmania major promastigotes were found to anchor themselves in the midgut and the stomodaeal valve via their flagella. The possible roles of the different internal. structures and their importance for the development of Leishmania parasites are discussed. (c) 2007 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.