Mesopeplum convexum is a species of marine bivalve mollusc belonging to the family Pectinidae, commonly known as true scallops. It is a distinctive species found in the waters around New Zealand.
Description
The shell of Mesopeplum convexum is typically biconvex, meaning both valves (halves) are convex, giving it a somewhat inflated appearance. The shell is roughly equivalve (the two valves are similar in size and shape) and suborbicular (nearly circular) in outline, though often slightly higher than long. Its surface is characterized by prominent radial ribs that extend from the umbo (the beak-like projection near the hinge) to the shell margin. These ribs can be smooth or may bear nodules or scales, varying between individuals and populations. The shell's "ears" (auricles), which are projections on either side of the hinge, are unequal in size. The coloration of Mesopeplum convexum is highly variable, ranging from shades of white, cream, yellow, orange, to reddish-brown, often displaying mottled or patterned designs. Adult shells typically reach a moderate size, generally a few centimeters in diameter.
Distribution and Habitat
This species is endemic to the temperate marine waters surrounding New Zealand. It is found in a range of subtidal environments, from relatively shallow depths down to several hundred meters. Mesopeplum convexum typically inhabits soft substrates such, including sand, mud, and gravelly seabeds. Like many other scallops, juveniles may attach themselves to objects or the seafloor using byssal threads, while adults often rest unattached on or partially buried in the substrate.
Classification
- Kingdom: Animalia
- Phylum: Mollusca
- Class: Bivalvia
- Order: Pectinida
- Family: Pectinidae
- Genus: Mesopeplum
- Species: Mesopeplum convexum (Hutton, 1873)
Ecology
As with other scallops, Mesopeplum convexum is a filter feeder, extracting plankton and suspended organic particles from the water column using its specialized gills. While generally considered sessile or semi-sessile, it possesses the ability to swim short distances by rapidly clapping its valves together, expelling water and creating a jet propulsion movement. This behavior is typically used to escape predators or move to more favorable locations. It plays a role in marine ecosystems as both a primary consumer and a food source for various bottom-dwelling predators.