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inhabit the digestive tract or body cavity of many invertebrates. 

 Levine (1977) provided a taxonomic revision and checklist of the 

 aseptate gregarine family Lecudinidae, which contains gregarine 

 parasites of insects. Ascocystis chagasi is the only gregarine 

 identified so far from New World sand flies (Scorza and Carnevali, 

 1981). 



According to Levine (1977), sporozoites in oocysts (spores) infect 

 the new host probably by being ingested. These enlarge, becoming 

 gamonts, and attach to the intestinal or coelomic wall where they 

 grow. Two gamonts become joined to one another in an association 

 known as syzygy and encyst together to form a gametocyst. One gamont 

 produces numerous male and the other numerous female gametes. 

 Fertilization (by fusion) occurs, forming the oocyst. Within each 

 oocyst form eight (rarely four) naked sporozoites. The oocysts or 

 gametocysts are passed out into the environment and remain there until 

 ingested by a new host. 



Early instar larvae become infected by ingesting oocysts passed 

 out in the feces of other larvae, or by eating oocysts adhering to 

 eggs deposited by infected females (Coelho and Falcao, 1964). 

 Liberated sporozoites penetrate the digestive tract and enter the 

 hemocoel and later enter the abdominal cavity of the fly. Gametocysts 

 full of oocysts are found attached to the accessory glands of females. 

 Mature oocysts pass into the accessory gland material, and attach to 

 the eggs deposited by the females. 



Gregarine infection rates reported in sand fly species other than 

 Lu . diabol ica range from less than one to 26% (Young and Lewis, 1977). 



Lien and Levine (1980) reviewed evidence that gregarines are host 

 specific and that they will only develop to the oocyst stage in their 



