Reproduction
H. leucospilota utilize both sexual and asexual reproduction as methods of reproducing.
Sexual Reproduction
Sexual reproduction in H. leucospilota allows for genetic diversity within the species. Sexual reproduction involves the release of the gametes, which are located in the gonad tubules (Purwati 2009). Males and females are distinctively separate in this species and contain sperm and oocytes in the gonads respectively (Purwati & Luong-van 2003). The males gonads are called the testes and contain sperm. In the females the gonads comprise of the ovarian tubules, which contain mature eggs during the spawning season. Individual females have been shown to release about 45000 eggs in a single event (Dabbagh et al. 2011). Spawning events are primarily controlled by environmental factors including food availability, temperature, photoperiod and the lunar cycle (Morgan, 2000). Once external fertilization occurs, successfully fertilized eggs pass through larval development, whilst being subject to environmental conditions (Soltani et al. 2010). Developed larvae must undergo settlement, and then survive the juvenile stage before making it to adulthood. See Cyclcity for more details.
Asexual Reproduction
Asexual reproduction, as in most echinoderms, is via fission of individuals. Fission takes place via annular constriction, leading to the rupture of the integument and organs, thereby causing the sea cucumber to separate into two (Conand, Morel & Mussard 1997). Consequential regeneration results in regenerated integument, which is always smaller than that of the original specimen, as well as thinner muscles (Conand, Morel & Mussard 1997).
Fission can take place throughout the year and there is evidence that fission may influence sexual reproduction activities (Purwati & Luong-van 2003). It has also been suggested the fission is significant to population maintenance, aiding more in increasing the number of individuals than sexual reproduction (Purwati & Luong-van 2003). Studies have estimated that about 12% of the population is undergoing regeneration due to fission at any one time, and success is more likely in posterior fission, resulting in a higher chance of survival (Conand, Morel & Mussard 1997).
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