_Atrina fragilis_ is a species of marine bivalve mollusk belonging to the family Pinnidae. These large and distinctive bivalves are commonly known as pen shells, a name derived from their elongated, flattened shell shape reminiscent of a writing quill.
Description & Characteristics
_Atrina fragilis_ can reach substantial sizes, with individuals often exceeding 30 centimeters in length. Their shells are characterized by a distinctive, fan-shaped profile, with a smooth, glossy exterior. The surface of the shell may exhibit intricate patterns of radial ribs, providing a unique textural element. The interior of the shell is pearly white and iridescent, showcasing the striking beauty of these marine creatures.
Habitat and Occurrence
_Atrina fragilis_ is typically found in shallow, coastal waters, favoring sandy or muddy bottoms. Their preferred habitat lies within the neritic zone, the region of the ocean extending from the shoreline to the edge of the continental shelf. This species exhibits a wide geographical distribution, being documented in various marine environments worldwide.
Taxonomy
The species _Atrina fragilis_ belongs to the Class: Bivalvia, Order: Ostreida, and Family: Pinnidae. These taxonomic classifications place _Atrina fragilis_ within a group of marine bivalves that share similar characteristics, including a hinged shell, filter-feeding mechanisms, and a sedentary lifestyle.
Feeding
_Atrina fragilis_, like other bivalves, are filter feeders. They draw in water through their siphons, filtering out microscopic algae and other organic matter for nourishment. This efficient feeding strategy contributes to the ecological balance of their marine ecosystems.
Image References