Identification Characteristics:
The largest bivalve species within the Mollusca phylum, it can be distinguished from other species by its extremely large size, reaching up to 137 cm in length and weighing over 200 kg. Key distinguishing features include the absence of large foot openings, the lack of dense growth lines, no boring into the substrate, elevated, undulating radial ridges, and underdeveloped shell scales. The mantle exhibits colors ranging from yellowish-brown to olive-green, with blue spots. The shell margin presents as a triangular ridge.
Biology and Ecology:
Found in coral reefs, typically residing on sandy substrates at depths starting from 1 meter. Its depth distribution is limited by the amount of light needed for photosynthesis by the symbiotic algae within the giant clam’s mantle.
Distribution:
- Vietnam: Offshore waters of Khánh Hòa Province (Sinh Tồn Island – Trường Sa Archipelago).
- Global: Australia
Value:
Possesses scientific and aesthetic value. As the largest bivalve in Vietnamese waters, some individuals could be introduced to marine parks for educational purposes, allowing students to study the species’ ecology and behavior.
Conservation Status:
A species with a limited distribution and rare occurrence. Populations are small and highly susceptible to depletion.
Red List Category:
EN A1d
Conservation Measures:
Included in the Vietnam Red Data Book (1992) and the IUCN Red List.