More than 2200 species of the wild flora and fauna photographed in Zihuatanejo, Guerrero, Mexico and the surrounding area.
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Molluscs of Zihuatanejo
PHYLUM MOLLUSCA
Ark Clam
Acar (Genus)
-Bivalves Class Bivalvia
-Subclass Autobranchia
-Infraclass Pteriomorphia
-Ark Shells and Allies (Order Arcida)
-Arks, Bittersweet Clams and Allies (Superfamily Arcoidea)
-Ark Clams (Family Arcidae)
-Genus Acar
The Ark Clams of the genus Acar are small to medium-sized marine bivalves in the family Arcidae, characterized by their thick, heavy shells with strong radial ribs and a somewhat rectangular to oval outline. Species of Acar typically have inequilateral valves and a straight hinge line bearing numerous small, interlocking teeth—a defining feature of ark clams. These clams inhabit shallow tropical and subtropical seas, commonly living attached to hard substrates such as rocks, coral rubble, or reef surfaces by means of byssal threads. As suspension feeders, they filter plankton and organic particles from the water column.
Description
Acar is a genus of small marine bivalve molluscs in the family Arcidae, commonly known as ark clams. They have two hinged shells, typically oval or somewhat elongated, with sculptured surfaces and a series of small teeth along the hinge. Shells are often whitish, cream, or brownish and may have ridges or fine growth lines.
Range
Species of Acar occur in marine waters in several regions of the world, particularly tropical and subtropical seas. The genus includes species found in the western Atlantic and Caribbean, including waters around Central America and the Caribbean coast of Mexico.
Habitat
These bivalves inhabit coastal marine environments, where they may attach to hard surfaces or live among rocks, coral rubble, shells, and other submerged structures. Some species occur in shallow coastal waters, while others inhabit deeper marine environments.
Diet
Acar species are filter feeders. They draw water through their gills and extract suspended microscopic food, including phytoplankton, bacteria, and organic particles. This feeding method allows them to obtain nutrients directly from the surrounding water.