Ceratobairdia
Ceratobairdia is an extinct genus of ostracod belonging to the order Podocopida and family Bairdiidae. Specimens have been found in Permian to Jurassic beds in North America, China, and Europe.
The genus is heavily ornamented, and a distinctive characteristic is that its valves have a flat ventral surface and a ventrolateral alate ridge The genus is also notable as a Lazarus taxon, disappearing in the Permian-Triassic extinction event and reappearing in the Carnian, an interval of at least 15 million years.