Studies on the Life-History and Biology of Oochoristica deserti n. sp. (Cestoda: Linstowiidae) from Desert Rodents

Abstract

Oochoristica deserti, from the kangaroo rat, Dipodomys m. merriami. and the ground squirrel, Citellus leucurus collected at Victorville, California, is described. The life-cycle of O. deserti was completed experimentally, which brings to 3 the number of known life-cycles in the Linstowiidae. The cysti-cercoids of O. deserti develop in the adult and larval stages of various coleopteran and lepidopteran insects, but not in acarid mites. Development of the larva in the insect, Tribolium confusum, was followed in detail from the onchosphere to the mature cysticercoid. Mature cysticercoids are formed in the insect 16 days after the ingestion of the onchosphere, and remain infectious for the definitive host at least for 87 days. Dipodomys m. merrami. D. panamintinus mohavensis. Citellus leucurus. Perognathus longimembris, and Mesocricetus auratus were experimentally infected with the cysticercoids of O. deserti. Gravid proglottids are formed and passed 22-23 days after the ingestion of the cysticercoids. Attempts to infect laboratory rats and mice were unsuccessful. The effect of temperature on the development of the cysticercoids was studied. As the temperature decreases the cestode larvae require a correspondingly longer time to attain maturity.