Photo 1: Three views of a large Idonearca truncate. (Specimen found at Willow Point Reef)
Idonearca
Well-preserved specimens of these thick shelled Cretaceous bivalves can be found at numerous locations on Vancouver Island. The umbo is raised and one edge is heavily truncated while the other edge tends to 'flare' upwards.. Slanted grooves in the ligament area (photo) form a 'V' in the direction of the umbo.
Photo 2: Idonearca truncate exposed in matrix
These bivalves exhibit both radial lines and concentric growth rings giving them a checkered pattern.
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