Psammosteidae
From Wikipedia, the free encyclopedia
This article is orphaned as few or no other articles link to it. Please help introduce links in articles on related topics. (November 2006) |
Psammosteidae Fossil range: Early Devonian |
||||||||
---|---|---|---|---|---|---|---|---|
Drepanaspis gemuendina and Tiaraspis subtilis
|
||||||||
Conservation status | ||||||||
Fossil
|
||||||||
Scientific classification | ||||||||
|
||||||||
Genera | ||||||||
|
The Psammosteidae are a family of flattened, benthic jawless vertebrates that lived in marine and estuary environments in Europe, Russia & North America. They arose during the Early Devonian, with the first (and best) known genus, Drepanaspis from the Hunsrück lagerstätte. The Psammosteids were the only heterostracans that survived the Upper Frasnian extinction event during the Late Devonian, dying out in the extinction event at the very end of the Devonian.
Many of the Late Devonian genera, such as Psammolepis, were among the largest heterostracans ever, growing to be at least 1.5 metres in width.