Blade Fire Coral

Blade fire coral grows as pale, upright plates on Caribbean reefs. Despite its coral-like skeleton, it packs a stinging punch that divers quickly learn to respect.

It is often confused with the closely related branching fire coral, which grows as rounded, antler-like branches. This species instead grows as flat, upright blades, the shape to check to tell the two apart.

This fire coral grows from an encrusting base into thin, upright blades or plates, angled to face into the current. The blade surfaces are smooth, but their edges are irregular and lined with small, stumpy bumps. The colour is pale brown or cream, with white tips along the blade edges. Fine pores across the surface let hair-like feeding and stinging structures reach out into the water.

Hair-like stinging structures on the surface detect passing zooplankton and inject venom to capture it, while separate feeding structures digest the catch for the colony. Symbiotic algae living in its tissue supply much of its energy through photosynthesis. It feeds both day and night, but feeds more at night. Touching this coral with bare skin causes a sharp, painful sting, despite it not being a true coral.

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  Branching Fire Coral

  Millepora alcicornis

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  Net Fire Coral

  Millepora dichotoma