Porites

Porites is a genus of reef-building hard corals in the family Poritidae, order Scleractinia, class Anthozoa. Found in tropical and subtropical oceans, Porites species form massive, columnar, or branching colonies composed of densely packed corallites encased in a thick calcium carbonate skeleton. The colonies may appear smooth or ridged, and surface texture often reflects habitat and growth form.

Porites corals host symbiotic dinoflagellates (zooxanthellae), which provide most of their energy through photosynthesis, while they also capture plankton at night. They typically inhabit shallow reef slopes, lagoons, and back-reef environments from near the surface to mid-depths, depending on species and light availability.

Reproduction varies: many Porites species are sexual broadcast spawners with synchronized spawning events, while others brood larvae or propagate asexually by fragmentation. Colonies tend to be long-lived and slow-growing, contributing substantially to reef structure and resilience of some ecosystems.

Porites is also important in paleoclimatology; its growth rings and stable isotope records are used to reconstruct past sea surface temperatures and rainfall patterns. The genus is sensitive to climate-related stressors, including thermal stress, ocean acidification, and disease, which can reduce growth or cause partial mortality.

Key species include Porites porites, Porites lobata, Porites astreoides, and Porites cylindrica, which occur across the Indo-Pacific and Atlantic-Caribbean regions.