Middle Ordovician – Late Ordovician
Protarea is an extinct genus of stationary epifaunal suspension feeders which have been interpreted to have hosted symbiotic algae in their tissues
Identification in Hand Sample:
- Form as thin films or sheets, always encrusting another species of marine animal
- Corallites (skeletons of single coral polyp) are closely spaced and polygonal with shallow calices.
- Coenenchyme narrow to absent
- Number of septa is usually 12
- Corallum of thin sheets, commonly encrusting; corallites close, coenenchyme narrow to absent, when present of closely contiguous thick trabeculae perpendicular to surface; septa 12, of contiguous trabeculae directed steeply upward and filling the lumen; tabulae absent.
- Thin incrusting coralla. Corallites polygonal with shallow calices. Septa 12.