Symphyllia wilsoni Propagation Guide
Propagating the closed brain coral Symphyllia wilsoni, now placed in Lobophyllia: dividing the colony down its valleys with a band saw so each frag keeps polyps and skeleton, plus its sexual spawning.
Overview
Symphyllia wilsoni is an Australian closed brain coral in the family Lobophylliidae. Reef Builders notes that the genus Symphyllia was reclassified into Lobophyllia in 2016, though the older name remains in common trade use; the record name is kept verbatim here. Reef Builders describes Symphyllia colonies as one solid skeleton with puffy tissue and thick walls, the polyp mouths sitting at the centre of the valleys.
Reproductive Mode
Symphyllia wilsoni is colonial rather than solitary, forming a single connected skeleton whose corallites share walls, with polyps lining the meandering valleys. Because tissue and skeleton make one continuous sheet, the colony can be divided into pieces that each carry living polyps, allowing both asexual fragging in captivity and sexual spawning in the wild.
Fragging / Asexual Propagation
Reef Builders states most LPS corals need a band saw for fragging. On this closed brain coral the cut is run down the valleys between the thick walls, taking sections that each contain polyps with their skeleton. A coolant of home-tank water tinted light amber with iodine disinfects the cuts, and each section is then dried and glued to a plug with a flat base.
Conditions for Propagation
Reef Builders reports that after gently basting off mucus, polyps extend within hours and cut edges expand within days. Stable parameters, gentle flow and clean water aid healing. The thick, puffy tissue produces heavy mucus, so allow it to dissipate to avoid irritating neighbouring corals during the recovery period.
Sexual Reproduction
As a zooxanthellate stony coral in the Lobophylliidae, Symphyllia wilsoni reproduces sexually by broadcasting gametes into the water column, where fertilisation produces planula larvae that disperse, settle and grow into new colonies. This pathway, distinct from fragmentation, is how the species renews populations on the reef.
Common Challenges
Because the polyps sit inside the valleys, Reef Builders warns that cutting there can damage them, so the blade must stay centred between the walls. The thick tissue tears if the saw wanders, and the coral is moderately aggressive with abundant mucus, so frags need spacing while they heal. Poor water quality slows recovery and promotes tissue recession at the cut edges.