Photo 1: A Pacific Littleneck Clam (Photo taken at Open Bay, Quadra Island.)
Varnish Clam: Nuttallia obscurata
Common Names: Purple or Dark Mahogany Clam
This is an invasive species of clam that was likely introduced from Japan through ballast water discharge in the 1980s. However, it is now becoming a commercially viable marketed under the name of 'savoury' clams. It has a relatively softy shell, prone to breakage upon harvesting.
It has a solid purple tinge and a flat shell with a brown coating (called a periostracum). It lives in the midtidal zone including regions that are susceptable to freshwater seeps.
References: Ministry of Agriculture and Lands Website