Sinularia asterolobata: Fragging and Propagation

Propagating the star-polyp Sinularia asterolobata by cutting its lobes and reattaching frags, with notes on its terpene chemistry, encrusting spread and wild spawning.

Overview

Sinularia asterolobata is a leather coral of the family Alcyoniidae notable for prominent star-shaped polyps when extended, giving the colony a distinctive texture. As a Sinularia its small polyps sit on the surface without prominent dimorphism, the tissue is supported by sclerites, and it relies mainly on symbiotic zooxanthellae for energy.

Reproductive Mode

Home propagation is asexual by fragging lobes, which heal into new colonies; the base can also encrust and spread over rock. Sexual broadcast spawning occurs in the wild but is not a home method.

Fragging / Asexual Propagation

A clean, sharp blade is used to cut a lobe or part of one. Because the slick tissue resists glue, the frag is banded, held in mesh or an onion bag, or set on rubble in low flow until it attaches; once anchored it can be glued. An iodine dip followed by a seawater rinse after cutting helps disinfect the wound and clear slime.

Conditions for Propagation

• Lighting: 75-200 PAR (medium)
• Flow: moderate, increased after attachment
• Temperature: 24-26 C
• Mature tank: at least about 3 months old
• Net out shed mucus that can irritate neighbours

Sexual Reproduction

Gonochoric octocoral colonies release eggs or sperm during broadcast spawning; fertilised eggs become planula larvae that drift, settle on hard substrate and bud into colonies. This natural pathway is not used for home propagation.

Common Challenges

Leathers periodically close and form a shiny waxy film that is shed within a few days before the polyps reopen. Sinularia produces diverse terpene-based metabolites and toxic, allelopathic compounds that can inhibit competitors, so the slime released during fragging should be removed from the main system.