Lithophaga inclusa

Jurassic

Lithophaga: Triassic to recent

Phylum: Mollusca
Class: Bivalvia
Order: Mytilida
Family: Mytilidae

Dorsoventral symmetry
Two valves
Growth lines
Umbo

Set 1:
Original shell material
Set 2:
Mould of boring in which the shell lived (can see the structure of the Coral Rag)

Lithophaga bore into hard substrates, and often preserve as the specimen from Set 2 has, as moulds of the borings they make. They lived as suspension feeders.

Lithophaga bore into rocks by secreting a weak acid. This dissolves calcareous substances, sometimes including other bivalve shells, into which the animal bores.