11th ICRS Abstract book - Nova Southeastern University

Poster Mini-Symposium 11: From Molecules to Moonbeams: How is reproductive timing regulated in coral reef organisms?
11.403
Reproduction of Madracis decactis (Cnidaria, Scleractinia) from Southern Bahia
Reefs, Brazil
Bruna CASTRO* 1 , Débora PIRES 1
1 Departamento de Invertebrados, Museu Nacional/Universidade Federal do Rio de
Janeiro, Rio de Janeiro, Brazil
The reproductive biology of the scleractinian coral Madracis decactis (Lyman, 1859) was
studied in southern Bahia reefs (16° to 18°S), the most extensive and richest reef areas of
the South Atlantic. Madracis decactis is one of the most widespread zooxanthellate
corals in Brazil and can be found at the edges of the reefs on exposed or cryptic areas.
The objective of this study was to investigate patterns of the sexual reproduction of M.
decactis. Information about sexuality, gonad arrangement, mode of development,
gametogenesis and temporal patterns of the reproductive cycle were obtained using
histological procedures. The results showed that M. decactis is a hermaphroditic species
and probably presents a brooding mode of development in southern Bahia reefs.
Reproductive cycle is annual and lasts about four months. Female and male gametes
started to develop at different times, with spermaries appearing in approximately the
second month of oogenesis and lasting about two months. Gametogenesis started on the
summer onset (December) and was complete at early autumn (April). Mature gametes
were not present in samples collected between the end of March and April. Evidences
suggested that fecundation, embryogenesis and the possible planulae release occurred
within this period, of approximately one month.
11.404
Spawning Seasons Of Scleractinian Corals in Southern Part Of Phuket, Thailand
Thanongsak CHANMETHAKUL* 1,2 , Hansa CHANSANG 3 , Niphon
PHONGSUWAN 3 , Kumpol MEESAWAT 1
1 Biology, Prince of Songkla University, Songkla, Thailand, 2 Biology, Phuket Rajabhat
University, Phuket, Thailand, 3 Marine and Coastal Resources, Phuket Marine Biological
Center, Phuket, Thailand
This study focuses mainly on the spawning season of scleractinian corals at the southern
part of Phuket Island. Spawning was monitored for the period of 15 months, from March
2000 to May 2001. A total of 12 species (Goniastrea aspera, G. pectinata, G. retiformis,
Favites halicora, F. abdita, Platygyra sinensis, Favia pallida, Acropora aspera, A.
formosa, A. austera, Pectinia paeonia และ Mycedium elephantotus), were investigated.
Initially, egg maturation of each species was investigated in the natural habitat.
Thereafter, 10 colonies of each coral species were collected and kept for monitoring in
the aquaria, where spawning activities were observed and recorded. The result of this
study revealed a hermaphrodite broadcasting mode of reproduction of all 12 species of
corals. However, the spawning period varied depending on the species. The spawning
period of all species investigated were related to the lunar cycle. Spawning took place
both during the full moon and new moon periods. All species spawned during dusk,
approximately 2 - 3 hours after the sunset. The spawning behavior of these 12 species of
corals can be categorized into 3 types 1) slowly released from the polyps 2) rapidly
expelled from the polyps. 3) attached to the mouth of each polyp. The colors of eggs also
varied among each coral species.
Key words: Spawning; Scleractinian corals; Thai waters; Phuket
11.405
Sexual Reproduction Of The Orange Colonial Coral astroides Calycularis (Scleractinia:
Dendrophyllidae) in The Mediterranean Sea
Stefano GOFFREDO 1 , Giulia MARCONI 1 , Gabriella GASPARINI* 1 , Maria Teresa
PUTIGNANO 1 , Francesco ZACCANTI 1
1 Department of Evolutionary and Experimental Biology, University of Bologna, Bologna, Italy
This study examines the sexual reproduction in a scleractinian coral living in temperate waters,
in the western and central Mediterranean Sea. Astroides calycularis is an azooxanthellate coral
that colonizes vertical walls, overhangs, cave entrances, and sea caverns with strong water
movement, from the surface to 50m in depth. The colonies have been collected monthly, from
April 2004 to September 2005 at Palinuro (Salerno, Campania, Italy) in the Southern
Tyrrhenian Sea. This is the first in-depth investigation of the reproductive biology of this
species. As expected for a member of the family Dendrophylliidae, A. calycularis was a
gonochoric coral: colonies were sex separated. Morphological aspects of male gametogenesis
were similar to those described in other dendrophylliids coral. During spermary development,
spermary diameter increased from a minimum of 31 µm during the immature stages to a
maximum of 673 µm during the mature stages. Female gametogenesis was characterized by the
conspicuous presence of lipid droplets in the oocyte cytoplasm, which were of phagocytic
origin. During oogenesis, oocyte diameter increased from a minimum of 30 µm during the
immature stage to a maximum of 1529 µm when mature. Embryogenesis took place in the
coelenteron indicating a brooding reproductive mode. Quantitative data on the annual
reproductive cycle indicate spring fertilization.
11.406
Sexual Reproduction in The Octocoral, carijoa Riisei, in Hawaii
Samuel KAHNG* 1 , Yehuda BENAYAHU 2 , Daniel WAGNER 3 , Nina ROTHE 4
1 College of Natural Science, Hawaii Pacific University, Kaneohe, HI, 2 Tel Aviv University, Tel
Aviv, Israel, 3 University of Hawaii, Honolulu, HI, 4 National Oceanography Centre, University
of Southampton, Southampton, United Kingdom
Since its initial discovery on Oahu in 1966, the azooxanthellate octocoral, Carijoa riisei
(Duchassaing and Michelotti, 1860), has spread across the main Hawaiian Islands and
proliferated in abundance. To help understand the substantial ecological success of C. riisei in
Hawaii, its sexual reproduction was examined. Carijoa riisei is gonochoric with a male to
female ratio of one. Gametogenesis is asynchronous, continuous, and does not exhibit seasonal
or lunar periodicity. Carijoa riisei spawns negatively buoyant eggs which suggest external
fertilization and possibly benthic larvae. Under favorable conditions, C. riisei exhibits high
polyp fecundity. Asynchronous, continuous spawning of gametes is an unusual mode of
reproduction which forgoes the advantages of concentrating gametes in space and time and
requires dense aggregations of male and female colonies in close proximity to ensure
fertilization success. Other life history traits such as fast growth, early age of sexual maturity,
vegetative propagation, and superior competitive ability enable C. riisei to form dense, multicolony
aggregations thereby facilitating sexual reproduction. Provided C. riisei can achieve a
critical density, this unusual sexual reproductive strategy probably enables it to exploit the
ephemeral availability of space across time with a high and continuous production of larvae.
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