Pedunculated cirripedes have two minute folds of skin, called by me the ovigerous
frena, which serve, through the means of a sticky secretion, to retain the eggs until they are hatched within the sack.
Size at sexual maturity is an important parameter in a population to define the fraction of sexually active population and make decisions about population status (sex ratio, operational and the proportion of ovigerous
females), which is also advantageous for managing fisheries because any failure in reproduction can be detected after the copulation period.
Although female blue crabs do not provide nutritional sustenance to the developing eggs, the size, aggressive behavior, and full calcification of the ovigerous
females serve to deter macrofaunal predators.
The theca of post-ovulatory follicles was continuous with the epithelial cell layer lining the ovigerous
narval comprising size composition, sex ratio and proportion of females according to their ovigerous
condition in relation to the bathymetric range and season.
Since then, I acquired the scientific description of Ampithoe prolata (Hughes and Peart 2013) which belongs to the family Ampithoidae, and I have encountered an ovigerous
female of the species deeply encrusted with 40-odd small brown eggs in seagrass in Hobsons Bay off Williamstown.
Monstrilloids lack egg sacs but they possess ventral ovigerous
spines that comprise two slender, spiniform structures of variable length in different species.
The reproductive stock was visually inspected once daily to detect the presence of ovigerous
During the first four months, parthenogenetic, ovigerous
iranica, observations for low percentage of ovigerous
females were seen by Devi and Smija (2013) for the freshwater crab Travancoriana schirnerae from India, and by Mansur and Hebling (2002) in the neotropical freshwater crab Sylviocarcinus australis from Brazil.
The proportion of ovigerous
females was 33% in January 2012 and <6% in July 2013, proportions that support the hypothesis of a biennial (or longer) reproductive cycle.
The tunica albuginea together with the germinal-epithelium (A single layer of epithelial cells with indistinct boundaries which lined the ovarian cavity) projected at several places into the ovocoel to form the characteristic ovigerous
lamellae or folds.