Tridacna squamosa (Squamosa Clam) Care Guide
Tridacna squamosa is a giant clam recognised by its prominent shell scutes, hardy among Tridacna and relying on zooxanthellae.
Compiled by Aquairi from published sources · Published · Updated
Overview
Tridacna squamosa, the fluted or scaly giant clam, grows to about 40 cm across. It is distinguished by prominent leaf-like ridged shell projections called scutes. The mantle tissue ranges from browns and purples to greens and yellows in linear or spotted patterns. It was described by Lamarck in 1819.
Taxonomy
- Family: Cardiidae
- Subfamily: Tridacninae
- Genus: Tridacna
- Scientific name: Tridacna squamosa
- Authority: Lamarck, 1819
Habitat
Its native range extends from South Africa to the Red Sea and to the Marshall Islands. It inhabits shallow coral reef ecosystems across the South Pacific and Indian Oceans.
Tank requirements
- Minimum tank volume: 250 L
- Temperature: 24-26 C (75-79 F)
- pH: 8.1-8.4
- Carbonate hardness (KH): 8-11 dKH
- Calcium: 380-450 ppm
- Magnesium: 1280-1350 ppm
- Specific gravity: 1.024-1.026
- Lighting: moderate reef lighting
- Lifespan: 30-80 years
Diet
The mantle hosts symbiotic dinoflagellate algae (zooxanthellae) that supply major nutritional support; the clam exposes its mantle during daylight to enable photosynthesis. It is relatively hardy among giant clams, requires moderate lighting, depends less heavily on photosynthesis than related species, and supplements its diet by consuming phytoplankton.
Compatibility
It is peaceful and reef-safe among reef fish. Mantle-nipping species such as angelfish, triggers and pufferfish should be avoided.
Conservation status
IUCN Red List: Least Concern. The species is listed on CITES Appendix II, which restricts international trade in the clam and its derivatives.
Tridacna squamosa Breeding Guide: Farm Aquaculture, Not Home Breeding
Overview
Tridacna squamosa, the fluted giant clam, is a photosymbiotic bivalve of the family Cardiidae that grows to about 40 cm across. Its mantle hosts symbiotic dinoflagellate algae (zooxanthellae) that supply much of its nutrition. Its native range spans from South Africa to the Red Sea and east to the Marshall Islands. It is not propagated in private aquariums; captive-bred stock originates from dedicated marine hatcheries.
Reproductive Mode
Like other giant clams, T. squamosa is a protandrous simultaneous hermaphrodite: the male gonad matures first, and the female gonad follows. Because the clam is sessile, it cannot pair-mate and instead uses broadcast spawning, releasing gametes directly into the water column. The normal sequence is for sperm to be released first, followed by eggs after a short interval, which reduces self-fertilization.
Propagation Setup
Controlled propagation is carried out in hatcheries, not home tanks. Mature broodstock are conditioned, then spawning is induced and gametes are collected in clean water. Pacific island nations have, for around forty years, invested in artificial production of Tridacna and Hippopus clams for food and income, rearing animals to market size in mariculture facilities.
Spawning and Larval Rearing
After external fertilization, the eggs develop into free-swimming larvae. Handling newly fertilized eggs until they become fully fledged veliger larvae is the most delicate part of the process; successful runs can yield tens or hundreds of thousands of settled juveniles. Larvae are initially aposymbiotic and must acquire zooxanthellae from the surrounding water before settling and metamorphosing.
Common Challenges
Home reef systems cannot rear clam larvae: planktonic eggs and larvae are removed by mechanical filtration and protein skimming, and synchronized spawning, larval feeding and zooxanthellae inoculation require dedicated hatchery control. For hobbyists the practical goal is healthy growth of farmed juveniles, not reproduction.