Pillar Coral in Cozumel
Pillar Coral (*Dendrogyra cylindrus*) in Cozumel: how to identify it, where colonies survive, and why it is Critically Endangered.
Tall vertical columns rising from a common base, covered in a fuzzy brown coat of extended polyps — one of very few hard corals whose polyps stay out during the day.
Quick ID
| Scientific name | Dendrogyra cylindrus |
|---|---|
| Group | Hard Corals |
| Typical size | Columns to 2–3 m tall |
| Depth range | 5–20 m |
| When to see it | Year-round |
| Active | Polyps extended day and night |
| Conservation status | Critically Endangered |
| Notes | Protected species |
Where You Will See It In Cozumel
Scattered colonies on the mid-depth reefs, including Paso del Cedral, Tormentos and Punta Tunich. Guides know the individual colonies.
Reliable sites: Paso del Cedral, Tormentos, Punta Tunich.
Behaviour
The daytime polyp extension makes it look furry, which is the fastest way to recognise it. Stony coral tissue loss disease has hit the species hard across the Caribbean, and colonies are now individually monitored in many marine parks.
Commonly Confused With
- Finger coral — Finger coral forms shorter, thinner branches with retracted polyps.
- Sponges — A brown fuzzy column is coral here, not sponge; sponges have visible openings.
Diving Etiquette And Safety
Critically Endangered and disease-affected. Keep well clear, do not touch, and follow any local guidance on gear disinfection between regions.
Part of the Cozumel marine life guide · see Cozumel dive sites · plan your Cozumel dive trip
Photo: Nick Hobgood, CC BY-SA 3.0, via Wikimedia Commons.
