(This genus is sometimes called Helioseris.)

This is always leafy, usually a single whorl. Calices are considerably larger than those of Agaricia, and are strongly inclined outwards towards the edge of the plate. Series of calices commonly occur in concentric rows.

Calices are commonly yellow, contrasting with the otherwise brown surface.

It has a range of surface features caused by varying development of the ridges between calices. In some the ridges are very ’broken’ forming numerous collines.