The New Zealand Scallop, Pecten novaezealandiae

The New Zealand Scallop, Pecten novaezealandiae, is a bivalve mollusk belonging to the family Pectinidae, the scallops.

This scallop is a native to New Zealand. It can be found in the North Island, Stewart Island, South Island, and the Chatham Islands. It is usually seen on sand, silt, and mud from low tide level to over 90 meters. Large populations can be found at depths of between 10 and 25 meters.

This species is entirely free-living, mobile and somewhat migratory. The two valves on this scallop are asymmetric. The valve on the left is convex while the valve on the right is flat. The concave valve has roughly 16 ribs. The coloration varies, however the valves are normally a whitish pink, but sometimes can be a dark reddish-brown. Sea stars and octopus are the scallop’s natural predators.

Individuals that are sexually mature are hermaphrodites. The season when the organisms spawn varies with location. Fertilization occurs and a planktonic larva is formed. This particular life stage is conserved for about three weeks. Metamorphosis occurs and the larvae changes from planktonic to a benthic existence via attaching itself to suitable substrate found on the seafloor. This attachment lasts until the individual is at least 5 millimeters in length. The individual then detaches itself from the substrate and begins to grow into an adult. Maturity is normally achieved by 18 months.

Image Caption: Penzance Bay. Credit: Stug.stug/Wikipedia (CC BY-SA 3.0)