Subergorgia suberosa, commonly called the yellow sea fan, is a gorgonian‑type soft coral (Octocorallia: Alcyonacea) forming planar, fan‑shaped colonies. Branches spread within a single plane to maximize exposure to prevailing currents for suspension feeding on plankton and organic particles.
Ecology & Biology
Feeding: polyps capture zooplankton and particulates from flow; energy comes from heterotrophic feeding rather than heavy reliance on symbiotic algae.
Reproduction: sexual broadcast spawning/planulation plus asexual fragmentation with re‑attachment to hard substrata.
Attachment/orientation: colonies anchor to hard substrates (rock, dead coral) and orient their fan plane roughly perpendicular to the main current.
Identification
Colonies are typically yellow to orange‑yellow; a stout trunk gives rise to pinnate branching forming one or a few fan sheets. Surface pores house small eight‑tentacled polyps. The internal skeleton consists of a proteinaceous axis withcalcareous sclerites providing strength and flexibility.
Colony size & Longevity
Fan height: commonly 30–100 cm; exceptional colonies to ~150+ cm.
Fan width: commonly 20–80 cm (variable with space and flow).
Life: long‑lived octocoral; colonies can persist for many years to decades on stable reefs.
Range & Habitat
Occurs on tropical–subtropical Indo‑Pacific outer reefs, slopes, walls and channels with moderate to strong currents, typically at ~10–40 m depth (and deeper). Prefers clear water and low sediment loads.
Threats & Conservation
Physical damage from storms, anchoring, fishing gear entanglement and diver contact.
Sedimentation/turbidity that clogs polyps and reduces feeding efficiency.
Climate stress (warming and acidification) that may affect skeletal deposition and colony integrity.
IUCN: no widely accepted global assessment—marked here as Not Evaluated (NE). Recommended: current‑swept reef buffers, no‑anchor zones and responsible diving/photography codes.
