How to Identify Brachiopod Fossils
- 1). Check to see if one of the two shells in the fossil is concave. If so, the brachiopod is Rafinesquina.
- 2). Check to see if the hinge on the brachiopod is pointed. If so, the brachiopod fossil is astrophic, and may be either Orthorhynchula or Rhynchotrema. If not, skip Step 3 because the fossil is strophic, and may be either Platystrophia or Hebertella.
- 3). Measure the diameter of the fossil at its largest point. If the fossil is larger than 1 cm, it is Orthorhynchula. Otherwise, it is Rhynchotrema.
- 4). Feel the fossil to see whether it has a ridged surface. If it does, it is Platystrophia. Otherwise, it is Hebertella.
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