Dolania oogenesis is unique in Ephemeroptera with the presence of only one oocyte per ovariole, low numbers of ovarioles, and complete resorption of 1/3-1/2 of the total number of ovarioles. This results in fecundity and egg length values which are respectively 1/20 and 2-4 times the values of most other mayflies. Approximately 70% of the linear growth of those oocytes which will mature takes place in a 2-3 week period during the late penultimate to early final larval stadia. Oocytes which will be resorbed remain small during this period until resorption occurs at about the time the other oocytes are mature. Resorbed oocytes probably do not offer a significant food reserve for the maturing oocytes or the female larva due to their small size, the timing of resorption and because the gut does not atrophy completely until the developing oocytes are nearly mature. Oocyte resorption is probably common and unimportant in most other mayfly species. / Dolania's large egg possesses a thick tough chorion and produces a well developed first instar 2.5-5 times the length of any other mayfly. It is probably soon capable of burrowing in the coarse sand substrate and of consuming a wide range of prey sizes. / The vitelline membrane possessed a globular ultrastructure. The chorion was composed of the endochorion and exochorion, which differed in paracrystalline ultrastructure and density. Chorionic channels traversed the entire width of the chorion and formed an interconnected meshwork in the inner endochorion. A suprachorionic layer was composed of an inner layer of long narrow fibers terminated by distal knobs approximately 46 nm in diameter, and an outer very thin granular layer. The follicle cells secreted the suprachorionic layer. Up to five funnelform micropyles were located at the equator of the egg. The inner portion of the micropyle canal was just large enough to permit the passage of sperm, and thus by its physical dimensions alone may limit polyspermy. / Source: Dissertation Abstracts International, Volume: 47-07, Section: B, page: 2745. / Thesis (Ph.D.)--The Florida State University, 1986.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_75889 |
| Contributors | FINK, THOMAS JOHN., Florida State University |
| Source Sets | Florida State University |
| Detected Language | English |
| Type | Text |
| Format | 160 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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