Merulina scabricula

Merulina scabricula is a reef-building coral in the family Merulinidae, recognizable by its distinctive laminar or plate-like growth form with contorted, wavy ridges radiating across the colony surface. Like other scleractinian corals, it relies on a symbiotic relationship with photosynthetic algae (zooxanthellae) housed within its tissues, which supply the coral with energy while the coral provides shelter and access to sunlight. Colonies contribute to the physical structure of reef ecosystems, offering habitat and shelter for a wide range of invertebrates and fish.

The species occurs across the Indo-Pacific, with recorded populations in American Samoa, Australia, Maldives, Thailand, Taiwan, China, and Japan. It inhabits marine neritic zones, generally on shallow reef flats and slopes where light penetration supports its symbiotic algae.

Merulina scabricula is classified as Endangered, with a decreasing population trend. It faces a broad combination of pressures, including coastal mining and quarrying, fishing and harvesting activities that damage reef substrate, and recreational activities such as diving and boating. Water quality degradation from domestic and urban wastewater, agricultural runoff, and other pollution sources adds further stress, while invasive species, disease, and native species outbreaks compound the damage.

Habitat shifting linked to broader environmental change also threatens the reef systems this species depends on.

Conservation efforts for reef-building corals generally include marine protected area designations, water quality regulation, and reef restoration initiatives, though species-specific interventions for Merulina scabricula are limited. Given the multiplicity of ongoing, unresolved threats operating simultaneously across its range, the species' population trajectory remains negative, and its long-term outlook depends heavily on broader improvements in reef management and water quality across the Indo-Pacific.