Pectinidae

Anatomical diagram of a typical hermaphroditic scallop

A live opened scallop showing the internal anatomy

Macro photo of a scallop showing some of its bright blue eyes.

Neural map of a giant scallop

Pectinidae[edit | edit source]

Pectinidae, commonly referred to as scallops, are a remarkable family of marine bivalve mollusks hailing from the superfamily Pectinoidea. The name Pectinidae originates from the Latin word "pecten," which translates to "comb." These creatures are renowned for their widespread presence, inhabiting all of the world's oceans but are conspicuously absent in freshwater habitats.

Taxonomy and Description[edit | edit source]

The Pectinidae family is part of the Pectinoidea superfamily. While Pectinidae is typically associated with scallops, it's noteworthy that other families within the Pectinoidea superfamily exhibit a somewhat analogous shell shape. Consequently, species from these families are occasionally also referred to as scallops.

Habitat and Behavior[edit | edit source]

Unlike the majority of bivalves, Pectinidae are primarily free-living. They demonstrate an impressive capacity for swift swimming across short spans and even migrating across the ocean floor. However, the behavioral patterns vary across species:

Some species adhere themselves to rocky substrates, becoming more or less permanent residents of that location.
Other species are attached in a rudimentary fashion through a secreted filament.
Yet, most species of Pectinidae are found lying on sandy substrates. Their advanced nervous system enables them to sense potential threats like starfish. In response, scallops can execute swift and unpredictable swimming maneuvers, facilitated by a unique form of jet propulsion. This propulsion is achieved by rapidly clapping their shell valves together, enabling them to escape predators.

Anatomy and Physiology[edit | edit source]

A standout characteristic of pectinids is the presence of multiple simple eyes situated around the mantle edges, setting them apart from most other bivalves. These eyes, coupled with a well-developed nervous system, not only aid in predator detection but also provide insights into their complex interactions with their environment.

Gallery[edit | edit source]

The great scallop, Pecten maximus, on the right, next to the native European oyster Ostrea edulis
A live individual of Placopecten magellanicus
A shell of a Pecten species with serpulid worm encrustation; Duck Harbor Beach on Cape Cod Bay, Wellfleet, Massachusetts
External mold of a scallop shell in the fossil genus Aviculopecten, from the Logan Formation, Lower Carboniferous, Ohio
Pedum spondyloideum from the North coast of East Timor