Reproduction in the externally brooding sea anemone Epiactis georgiana in the Antarctic Peninsula and the Weddell Sea
Rodriguez, E.; Orejas, C.; Lopez-Gonzalez, P.J.; Gili, J.M. (2013). Reproduction in the externally brooding sea anemone Epiactis georgiana in the Antarctic Peninsula and the Weddell Sea. Mar. Biol. (Berl.) 160(1): 67-80. http://dx.doi.org/10.1007/s00227-012-2063-x
In: Marine Biology: International Journal on Life in Oceans and Coastal Waters. Springer: Heidelberg; Berlin. ISSN 0025-3162; e-ISSN 1432-1793, more
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| Authors | | Top |
- Rodriguez, E.
- Orejas, C.
- Lopez-Gonzalez, P.J.
- Gili, J.M.
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| Abstract |
External parental care is uncommon among actiniarians but common in Epiactis species. Here, several aspects of reproduction are analyzed for of one of them, Epiactis georgiana. Samples were collected in December, January, February, March, and April in the Antarctic Peninsula and the eastern Weddell Sea, during 1998, 2000, 2002, and 2003. Most sexually mature individuals of E. georgiana are male or female, but some are hermaphrodites. This is the first report of hermaphroditism in E. georgiana, which is the third species of the genus with this sexual pattern. The results suggest that oogenesis starts in December and that at least two generations of oocytes overlap; a third generation is often brooded externally. Putative fertilization is likely internal, and larvae and/or embryos are externally brooded on the distal part of the adult column until an advanced developmental stage. Apparently E. georgiana reproduces seasonally, probably releasing the embryos/larvae in the last months of the austral spring (December). Inter-individual variability was observed in gametogenesis. In addition, specimens from the Antarctic Peninsula were larger than those from the Weddell Sea. This study represents the first step in understanding the reproductive mode of E. georgiana. |
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