Reproduction Preferences Additional Information | - Mature individuals can be recognised by swollen genital papillae at the base of the arms. Eggs escape through splits which appear in the pinnule walls, and adhere in groups to the external wall of the pinnule where fertilization takes place. The embryos are held on the pinnules in a mucous net during which time the female holds its arms close together in what has been described as brooding behaviour, allowing spawned females to be readily identified. Embryos remain attached in groups of up to 20 for four or five days (Chadwick, 1907 cited in Nichols, 1991). The embryos hatch as free-swimming larvae which, after a short pelagic phase, attach to the substratum and develop a short stalk. At this stage they are known as pentacrinoid larvae. The pentacrinoids eventually detach and by this stage the small, prehensile cirri have developed on the undersurface of the disc.
- The season of spawning for Antedon bifida is universally stated as May to July. However, Nichols (1991) observed that mature oocytes and active sperm were present in every month of the year although a spawned out condition is seen in samples every so often. Therefore, although shed embryos have only been seen in the period May to July, it is possible that, like the congeneric Antedon mediterranea, Antedon bifida reproduces all year. Other evidence leads Nichols (1991) to suggest that Antedon bifida may have two shedding strategies, also shedding directly into the seawater as in the case of the congeneric Antedon petasus.
- In later work Nichols (1994) suggests that the maintenance of gonads at a high level of maturity throughout the year is a life-history trait developed to tolerate the predation of expendable and easily-regenerated gonads.
- Brooding female comatulids are almost insensitive to mechanical stimuli (Lahaye & Jangoux, 1984).
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