Studies of the fissiparous holothurian Holothuria parvula (Selenka) (Echinodermata: Holothuroidea)

• Published in: Journal of experimental marine biology and ecology 1987-09, Vol.111 (3), p.195-211
• Main Authors: Emson, R.H., Mladenov, P.V.
• Format: Article
• Language: English
• Subjects: Asexual reproduction; Bermuda; Biological and medical sciences; Echinodermata; Fundamental and applied biological sciences. Psychology; Holothuria parvula; Invertebrates; Marine; Regeneration; Sea cucumber; Sexual reproduction
• ISSN: 0022-0981; 1879-1697
• DOI: 10.1016/0022-0981(87)90028-1

A Bermudan population of the fissiparous holothurian Holothuria parvula (Selenka) was sampled over a 13-month period (1984–1985). Fission was most frequent in the summer when water temperatures were > 25 °C. During fission, the holothurian split into roughly equal parts, and there was little difference in survival of the oral and anal ends. Regeneration of a new gut is a priority and feeding was possible within 2 months of fission. The majority of growth following fission occurred between April and July, just prior to the peak occurrence of fission. Many individuals were fully regenerated within a year, so fission is possibly an annual event. Individuals showing evidence of multiple fission were found. The capacity for sexual reproduction was limited and it appeared to occur mainly during the summer, which was also the peak period for asexual reproduction. No small (< 18 mm) individuals were ever found suggesting that larval recruitment to this population had not recently been successful. The population has probably been maintained recently by fission.