This thesis presents results of the histological study of oogenesis in the nymphs of 5th instar, variously aged adult females of known age and adult females of Velia caprai ((Heteroptera: Gerromorpha: Veliidae) of unknown age that were collected in the field. Oogonia in the germarium and the first oocytes that are forming in previtellarium were observed in the nymphs of the 5th instar. Their vitellarium is empty. The first vitellogenetic oocytes appear in vitellarium of ovarioles at 7 days old adult females. Oocytes in advanced stage of vitellogenesis were observed at 25 days old adult females. The secretion of chorion starts at 42 days old adult females. Advanced stage of oogenesis (fully chorionated eggs) was found at 60 days old adult females, at adult females collected in the field, during the period September ? November (2009), and at adult females after overwintering. Females of Velia caprai reach sexual maturity before overwintering, their eggs can be fertilized by spermatozoa from own spermatheca. These females can lay eggs from autumn to the spring. After reaching sexual maturity of adult females, oogenesis of this species seems to be continual.
Identifer | oai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:50122 |
Date | January 2011 |
Creators | MÁLKOVÁ, Karolína |
Source Sets | Czech ETDs |
Language | Czech |
Detected Language | English |
Type | info:eu-repo/semantics/masterThesis |
Rights | info:eu-repo/semantics/restrictedAccess |
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