Mossy ark

Arca imbricata

Family Arcidae - arks

Bivalve (2 shells); shell rectangular and elongate; color reddish brown mixed with lighter streaks; hairy brown outer skin (periostracum); hinge area long and straight; radial ridges crossing concentric growth lines, giving a beaded appearance to the shell; strong ridge from beak to posterior margin; anterior end rounded, posterior end more squarish with 2 pointed angles; ventral margin of shell with central flexure; beak somewhat pointed, arched gap between beaks.
Similar Species
The white miniature ark has a wider beak and weaker flexure (if present) on ventral margin and is white.
Gulf, attaches to hard substrates
Maximum Size
6.3 cm (2 1/2 in)
Other Common Names
Previous Scientific Names