Reproduccion Corales, Diploria

Sexual reproduction of the reef-building coral Diploria labyrinthiformis (Scleractinia: Faviidae), in the Colombian Caribbean
Elvira M. Alvarado Ch.1, Rocío García U.2 & Alberto Acosta3
1 2 3 Centro de Investigaciones Científicas (Museo del Mar), Universidad de Bogotá Jorge Tadeo Lozano, Santafé de Bogotá, D.C., Colombia. Fax: 57-1-2812840; elvira.alvarado@utadeo.edu.co Department of MarineSciences, University of Puerto Rico - Mayaguez Campus, P.O Box 908, Lajas P.R 00667; rochy98@hotmail.com Pontificia Universidad Javeriana, K 7 No 43-82, Ed Carlos Ortiz. Oficina 502, Bogotá, Colombia; laacosta55@hotmail.com Received 26-IV-2002. Corrected 06-I-2003. Accepted 20-II-2003.

Abstract: Sexual reproduction of the coral Diploria labyrinthiformis was studied for the first time. Monthlyhistological analyses at the Corales del Rosario National Park (Colombian Caribbean) from May 1997 to April 1998 show that D. labyrinthiformis is a hermaphroditic broadcasting species. It presents an annual gametogenic cycle with a 10-11 month period for gonad investment, in which oogenesis begins in August and ends in MayJune. Spermiogenesis is short because sperm cysts were only observed in Maytissue samples. In histological collected in May, an average of four mature eggs and six spermatic cysts per fertile mesentery were found. The mean diameter of mature eggs was 297 µm (± 97 SD) and 90 µm (± 33) for spermatic cysts. Rapid maturation of eggs from stage II to stage III coincides with increases in air temperature, high number of solar hours per month, decreases in wind velocity and absenceof rainfall. Reproductive effort for D. labyrinthiformis (14.07 mm3/cm2/year) was similar to other Faviidae species. Although gamete release was not observed in the field, the absence of gonads in histological samples in June suggests spawning between May 25 (five days after full moon) and June 24. This event coincides with high air temperature, low number of solar hours per month, low windvelocity, and initiation of the rainy season. The earlier spawning time of this species differs from other species of the same family known for the Caribbean region. Rev. Biol. Trop. 52(4): 859-868. Epub 2005 Jun 24. Key words: Diploria labyrinthiformis, coral reproduction, gametogenesis, Caribbean coral reefs, Colombia.

Studies on sexual reproduction of hermatypic corals have increased during thelast two decades, with information of about 30% of the known species currently available. From 91 species of Faviidae within the Indo-Pacific region, information of only 40 species is known (Kojis and Quinn 1982, Harriot 1983, Harrison and Wallace 1990) and from 17 species of the Caribbean region, no more than eight species have been studied (Szmant 1986, Soong 1991, Acosta and Zea 1997). Faviidspecies are mainly hermaphroditic and present gonads developing as local thickenings of the mesentery, in contrast with

those of Pocilloporidae, which are connected by a short stalk to the mesenteries and projected into the body cavity (Rinkevich and Loya 1979) or those of Siderastrea siderea, which are attached to the mesenterial filaments (Alvarado and Guzman unpublished). In the ColombianCaribbean, information on the reproductive biology of corals is available for the following species: Porites porites (Hernández and Manrique 1991), Acropora palmata (García 1994), Acropora cervicornis (Sanjuan 1995), Tubastrea coccinea (Uscategui 1996) and Montastraea cavernosa (Acosta 1992, Acosta and Zea 1997) as well as
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Rev. Biol. Trop. (J. Trop. Biol. ISSN-0034-7744) vol. 52 (4): 859-868,December 2004 (www.tropiweb.com)

on spawning season of Montastraea annularis and M. faveolata (Sánchez et al. 1999). Diploria labyrinthiformis is a common species of the coral community in some areas of the Caribbean region and yet its reproductive biology is, so far, unknown. Previous studies on reproductive characteristics of Diploria strigosa (Wyers 1985, Szmant 1986, Wyers et al. 1991,...