#Crepidula fossil

[uk-fossils]

Crepidula Fossil Bivalve – Lower Miocene, Clallam Formation, Washington USA, Genuine Specimen

A genuine and well-preserved Crepidula fossil bivalve from the Lower Miocene epoch, approximately 16–20 million years old. This fossil was discovered in the Clallam Formation of Northwestern Washington, USA, an important geological unit known for preserving a diverse assemblage of marine molluscs.

The genus Crepidula, commonly known as slipper shells, is a marine gastropod mollusc (often mistaken for a bivalve due to its shell shape) with a distinctive internal shelf structure. This specimen reflects the shallow marine environments of the early Miocene in the Pacific Northwest.

Fossil Type: Gastropod (commonly called a slipper shell, not a true bivalve)

Genus: Crepidula

Geological Age: Lower Miocene (approx. 16–20 million years ago)

Formation: Clallam Formation

Depositional Environment: The Clallam Formation was deposited in a shallow, warm marine setting with good water circulation, supporting abundant marine life. The sediments include sandstone and siltstone beds that preserved mollusc shells in fine detail.

Morphological Features:

Convex outer shell with a smooth to slightly ridged surface

Internal “shelf” typical of Crepidula species visible in some specimens

Preservation may include original shell material or internal moulds

Notable:

Authentic specimen from the Clallam Formation, Washington State

A well-known genus with evolutionary and ecological interest

Ideal for fossil collectors, educators, and marine paleontology enthusiasts

Actual item shown – photo depicts the exact specimen you will receive

Authenticity: All of our fossils are 100% genuine natural specimens and come with a Certificate of Authenticity. The photo includes a 1cm scale cube for reference – please view the image for accurate sizing.

Add this genuine Crepidula fossil to your collection – a classic marine mollusc from the Lower Miocene seas of the Pacific Northwest, showcasing a beautifully preserved snapshot of ancient ocean life.