Pacific plate limpet
Tectura scutum
This large, flat limpet has a bluish-white interior with a dark apical blotch and a marginal band or spots on the inside (photo). The apex is slightly anterior to the middle and is not directed anteriorly. It is oval in shape and the length is usually less than 1.3 times the width. The height is less than 1/3 the width. It has no prominent radial ribs but may have low, flat-topped ridges. The color is brownish, olive-green, or greenish, usually spotted, streaked, or checkered with white. Length to about 6.3 cm. This is the only Pacific limpet with brown tentacles. The edges of the shell are thin and easily broken.