In addition, there are four extinct families known only from fossils.

It is divided into 4 families, one extinct.

Permotipulidae is an extinct family of insects within the order Protodiptera.

This extinct family of sharks existed in the Carboniferous period.

Clearly the greatest problems in tracing heraldry relate to long extinct families.

Several fossil species are known, including two extinct families.

No fossil larvae of this extinct family have yet been discovered.

Elephant birds are an extinct family of birds which can not fly.

Chalicotherium, a member of the related extinct family Chalicotheriidae, also appears for the first time.

Symmoriidae is an extinct family of sharks from the Carboniferous period.