The sun coral Tubastraea coccinea Lesson, 1829 (Dendrophylliidae) is a widely distributed shallow-water scleractinian that has extended its range to non-native habitats in recent decades. With its rapid spread, this coral is now one of the main invasive species in Brazil. Its high invasive capability is related to opportunistic characteristics, including several reproductive strategies that have allowed it to disperse rapidly and widely. To better understand the reproductive biology of T. coccinea and aid in developing management strategies for invaded areas, we investigated aspects of its reproductive performance and life cycle, including the effects of colony size, seawater temperature and salinity, and lunar periodicity on offspring production and larval metamorphosis competence. A total of 18,139 offspring were released in different developmental stages, mainly from the larger colonies, which also produced larvae with longer competence periods. The main reproductive peak occurred during the First Quarter and New Moon phases and was highest in water temperatures around 26°C. Together, these results help to explain the rapid expansion of T. coccinea into non-native habitats such as the Caribbean and southwestern Atlantic, and will inform actions of the recent Brazilian National Plan for the prevention, eradication, control, and monitoring of sun corals.

Embryonic stages and larvae released from each colony of Tubastraea coccinea kept in open water aquarium system were sampled once a day and placed in separate aquaria according to their respective release dates. These larvae were monitored every 24 h for sampling different ontogenetic stages (newly settled, settled, early metamorphosis, metamorphosed, and recruit), which were then transferred to new aquaria (300 to 500 ml) according to the stage (also kept separated by parent colony). The time for larvae to reach each developmental stage was tracked.

To assess the reproductive performance of T. coccinea and the potential effects of biotic and abiotic factors on its fitness, released offspring were monitored for 91 d. During the experiment, we tested the number of offspring released (number of embryos and larvae per day) as the response variable, and lunar periodicity, temperature, and salinity as explanatory variables. Temperature and salinity were measured with a YSI Model 30 Handheld Conductivity, Salinity, & Temperature meter, once a day in surface water at the location where the water used in the experiment was obtained.

All necessary information are in the spreadsheets as comments to some cells and also in the scientific paper.