Sarcophyton glaucum: Fragging and Propagation
Propagating the yellow toadstool Sarcophyton glaucum by cutting the capitulum and reattaching frags, with notes on its diterpenoid chemistry, waxy shedding and reef-flat distribution.
Overview
Sarcophyton glaucum is a toadstool leather coral that grows up to about 80 cm in the wild, typically on reef flats, in lagoons and on seaward slopes, and ranges from the Red Sea to the western Pacific. It is an octocoral whose polyps bear eight tentacles, and in the Red Sea it is one of the most prevalent soft corals of the family Alcyoniidae. Photosynthetic zooxanthellae supply most of its energy.
Reproductive Mode
In the aquarium the species is multiplied asexually by fragging the fleshy crown; cuttings regenerate into new colonies. Sexual broadcast spawning occurs in nature but is not the route used by hobbyists.
Fragging / Asexual Propagation
A sterile sharp blade is used to cut a wedge from the capitulum margin, which is then divided into frags. Because the slick surface resists adhesive, frags are banded, held in mesh or onion bag, or set on rubble in low flow to attach on their own. Many propagators dip cuttings in iodine and then clean seawater to disinfect and remove slime.
Conditions for Propagation
- Lighting: 75-200 PAR (medium)
- Flow: moderate, increased once anchored
- Temperature: 24-26 C
- Mature tank: at least about 3 months old
- Net out shed mucus to protect neighbours
Sexual Reproduction
Gonochoric octocoral colonies release gametes during mass spawning; fertilised eggs develop into planula larvae that disperse before settling and budding into new colonies. This natural pathway is not used for home propagation.
Common Challenges
Recovering frags commonly retract and form a shiny waxy film that is shed within days as the polyps reopen. S. glaucum produces cembrane terpenes, including the diterpenoid sarcophytol A, which protect against pests, fouling and competitors; the slime released while cutting should be removed so it does not irritate other corals.