Appearance and development of skeletal structures in Holothuria scabra larvae and epibiont juveniles
Rasolofonirina, R.; Jangoux, M. (2005). Appearance and development of skeletal structures in Holothuria scabra larvae and epibiont juveniles. SPC Beche-de-mer Information Bulletin 22: 6-10
In: SPC Beche-de-mer Information Bulletin. Secretariat of the Pacific Community: Noumea. ISSN 1095-4943, meer
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| Auteurs | | Top |
- Rasolofonirina, R.
- Jangoux, M., meer
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| Abstract |
Various types of calcareous structures have been observed in Holothuria scabra sea cucumber larvae and epibiont juveniles at various ages and stages of development. An unpaired calcareous body can be observed as early as the dipleurula stage (less than two days after fertilisation); it is located in the posterior part of young larvae (36 h), grows, changes appearance (from a star, it becomes a half-sphere) and can still be found in epibiont juveniles. The madreporite appears in older auricularia (10 days) in the form of a curved stalk located at the base of the water ring canal; it develops to form a screened sphere in pentactulae and juveniles. Tables are recognisable in doliolaria larvae (15 days) and the initial formation of the peripharyngeal calcareous ring can been observed in pentactulae (17 days). The first podia rods and perforated disks appear in 20-day-old juveniles and anal plates from day 22 onwards, but button spicule only develop at the end of the epibiont life stage (45 days). |
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