Windowpane Oyster, Placuna placenta
The windowpane oyster, Placuna placenta, alternatively known as capiz, is a bivalve marine mollusk belonging to the family Placunidae. Among the species within the genus, only the P. placenta has an outer shell that is sufficiently translucent for commercial use.
This mollusk can be found from the shallows of the Gulf of Aden, to around India, then Malaysia to the southern South China Sea, and around the Philippines. Capiz, a province in the Philippines, gets its name from this shell which flourishes copiously there. These can normally be found in muddy or sandy shores on bays, coves, and lagoons to a depth of around 330 feet. Windowpane oysters are cultivated in some areas as well. Similar to other bivalves, they consume plankton that is filtered from the water via water passing through its slightly opened shell; the shell is shut if above water during low tide.
The nearly flat and concave shells of the capiz can grow to over 5.9 inches in diameter, reaching maturity between 2.8 to 3.9 inches; securing the shells is a ligament in the shape of a V. Both male and female oysters are distinguished by the color of the gonads. Fertilization is an external process and larvae are free-swimming like plankton for 14 days or attached to surfaces by means of byssal thread during metamorphosis, eventually settling in the bottom.
Image Caption: Capiz Shell. Credit: Johnnyflex/Wikipedia (CC BY-SA 3.0)