|Title||The life cycle of Leptorhynchoides thecatus (Linton), an acanthocephalan of fish|
|Publication Type||Journal Article|
|Year of Publication||1949|
|Journal||Journal of Parasitology|
1. The life cycle of Leptorhynchoides thecatus has been experimentally reproduced in the laboratory. 2. The amphipod, Hyalella azteca, serves as the intermediate host, and the rock bass, Ambloplites rupestris, as the definitive host. 3. The eggs of Leptorhynchoides thecatus are ingested by the amphipod intermediate host. Hatching takes place within the intestine. The acanthor of Leptorhynchoides thecatus penetrates the epithelium of the host and locates between it and the serosa of the intestine. 4. The embryo undergoes a period of growth and development attached to the host intestine, producing a rounded bladder-like acanthella projecting into the hemocoele of the host. 5. Fourteen days after entering the intermediate host the acanthella separates from its attachment to the intestine of the amphipod, and enters into a period of development free within the hemocoele of the host. 6. Thirty-two days after the embryo is ingested by the amphipod it has developed into a juvenile acanthocephalan capable of infecting the fish definitive host. 7. The juveniles of Leptorhynchoides thecatus within the hemocoele of Hyalella azteca contain all the organs of the adult with one exception: the juvenile females do not have the ovary completely formed. 8. Upon ingestion of Hyalella azteca by the fish host, the juvenile ACANTHOCEPHALA are released into the fish stomach and attach to the walls of the pyloric cecae. 9. Four weeks after entering the fish host the juvenile male acanthocephalan has completed its development. During this period, the female completes formation of the ovary and eight weeks after entering the fish it passes mature eggs.