Zoanthids are often referred to as colonial anemones, but in fact belong to their own unique order.  In the Pacific Northwest the orange zoanthid is often encountered by scuba divers.  These colonies exist as large mats of individuals all connected together at their base by a tissue layer.

Zoanthids are distributed around the world with many colourful tropical varieties readily available in the aquarium trade.  Some zoanthid species contain a highly toxic substance called palytoxin, and uninformed people that maintain saltwater aquariums have been exposed to this toxin.  Zoanthids are often recommended to new saltwater aquarist as they are very colourful, and relatively easy to keep.  Exposure occurs during tank maintenance, as well as propagation.  New colonies are easily grown from a cutting of the original colony.  Many aquarists in the past did not wear protective gloves, or eye protection when breaking off a new colony.  Fortunately these poisonings are relatively rare.