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Abstract Reproduction, embryological development, and settlement of corals are critical for survival of coral reefs through larval propagation. Yet, for many species of corals, a basic understanding of the early life‐history stages is lacking. In this study, we report our observations forex situreproduction in the massive reef‐building coralPoritescf.P. lobataacross 2 years. Spawning occurred in April and May, on the first day after the full moon with at least 2 h of darkness between sunset and moonrise, on a rising tide. Only a small proportion of corals observed had mature gametes or spawned (14–35%). Eggs were 185–311 μm in diameter, spherical, homogenous, and provisioned with 95–155 algal cells (family Symbiodiniaceae). Males spawned before females, andex situfertilization rates were high for the first 2 h after egg release. Larvae were elliptical, ~300 μm long, and symbiotic. Just 2 days after fertilization, many larvae swam near the bottom of culture dishes and were competent to settle. Settlers began calcification 2 days after metamorphosis, and tentacles were developed 10 days after attachment. Our observations contrast with previous studies by suggesting an abbreviated pelagic larval period inPoritescf.P. lobata, which could lead to the isolation of some populations. The high thermal tolerance and broad geographic range ofPoritescf.P. lobatasuggest that this species could locally adapt to a wide range of environmental conditions, especially if larvae are locally retained. The results of this study can inform future work on reproduction, larval biology, dispersal, and recruitment inPoritescf.P. lobata, which could have an ecological advantage over less resilient coral species under future climate change.
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Spawning, embryogenesis, settlement, and post‐settlement development of the gorgonian Plexaura homomalla
Abstract Patterns of population biology and community structure can be studied by looking closely at the ontogeny and reproductive biology of reef‐building organisms. This knowledge is particularly important for Caribbean octocorals, which seem to be more resilient to long‐term environmental change than scleractinian corals and provide some of the same ecological services. We monitored the development of the black sea rod,Plexaura homomalla, a common, widely distributed octocoral on shallow Caribbean reefs, from eggs to three‐polyp colonies over the course of 10 weeks. Gametes were collectedex situon St. John, U.S. Virgin Islands, during spawning events that occurred 3–6 days after the July full moon. Cleavage started 3.0 hr after fertilization and was holoblastic, equal, and radial. Embryos were positively buoyant until becoming planulae at 3 days after fertilization. Planulae were competent to settle 4 days after fertilization. Symbiodiniaceae began infecting polyps ~8 days after fertilization. Overall, development was typical for Caribbean octocorals, except for an increase in the number of embryos between 3.5 and 6.0 hr after fertilization.
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- Award ID(s):
- 1756381
- PAR ID:
- 10451098
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Invertebrate Biology
- Volume:
- 140
- Issue:
- 2
- ISSN:
- 1077-8306
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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