Biddulphiaceae is a family of diatom, the only family in the order Biddulphiales.

[1] The Biddulphiaceae are distinguished from the Eupodiscaceae by their pseudocelli, where the Eupodiscaceae have fully developed ocelli.

[2] Both families commonly inhabit the littoral zone of the ocean, close to the shore.

[3] Sixteen species of Biddulphiaceae are found on the west coast of India.

This diatom article is a stub.