Record Details
The morphology and sexual maturation of Philometra americana Ekbaum, 1933 (Dracunculoidea:Philometridae)
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | The morphology and sexual maturation of Philometra americana Ekbaum, 1933 (Dracunculoidea:Philometridae) |
| Names |
Carter, Richard Thomas
(creator) Pratt, Ivan (advisor) |
| Date Issued | 1967-10-13 (iso8601) |
| Note | Graduation date: 1968 |
| Abstract | The female Philometra americana Ekbaum, 1933 is a common subcutaneous parasite of the starry flounder, Platichthyes stellatus (Pallas) of Yaquina Bay, Lincoln County, Oregon. Maturation of this worm produces noticeable red cysts subcutaneously between the fin and tail rays and similarly on the operculum. The gravid female penetrates the epidermis and leaves the fish. In sea water, the female bursts to release thousands of larvae which are presumably then ingested by an intermediate host. One thousand two hundred twenty-four starry flounders were examined and 280 fish were found to be infected. Three hundred forty-three female P. americana were collected and studied. No male was found. The percent of infection decreased as the size of the flounders increased. This suggests that the intermediate host for P. americana is primarily in the diet of the smaller fish. Collection data indicates that there is no seasonal occurrence of the infection in this locality, but no conclusion was reached as to the time required for the parasite to become gravid and leave the host fish. The digestive and reproductive systems of P. americana change drastically as the animal matures. There is a multiplication of cells in the intestinal wall during maturation. There is an atrophy of the anus, vagina and vulva by the time the animal has become pink in color with worm-like embryos in the uterus. The growth of the embryos in the uterus causes the worm to become two to three times larger than the immature worm. |
| Genre | Thesis/Dissertation |
| Topic | Philometra americana |
| Identifier | http://hdl.handle.net/1957/47069 |
