Name:
Archaeothyris.
Phonetic: Ar-kay-oh-thigh-ris.
Named By: Robert R. Reisz - 1972.
Classification: Chordata, Tetrepoda, Synapsida,
Pelycosauria, Ophiacodontidae.
Species: A. florensis (type).
Type: Carnivore/Insectivore.
Size: 50 centimetres long.
Known locations: Canada, Nova Scotia. Czech
Republic, N�řany. USA, Ohio.
Time period: Kasimovian of the Carboniferous.
Fossil representation: Three specimens.
Archaeothyris
is currently enjoying recognition as the oldest confirmed synapsid in
the fossil record. Although there is some evidence that the synapsids
evolved earlier, the fragmentary state of these fossils has made their
classification impossible to determine with certainty. This means that
Archaeothyris continues to represent the branch of
the evolutionary
line that would result in the pelycosaurs, therapsids and early mammals.
As
a living creature Archaeothyris looked like a
modern day lizard,
although at fifty centimetres long, it was one of the larger carnivores
that were scurrying around the carboniferous forests. Its mouth had
teeth that were small and sharp with two enlarged canines, suggesting
an insectivorous diet at a time when the arthropods grew larger than
they do today. Although Archaeothyris is
potentially an evolutionary
giant, its lifestyle would have been more or less the same as its other
reptilian contemporaries.
Further reading
- Pelycosaurian Reptiles from the Middle Pennsylvanian of North
America. - Bulletin of the Museum of Comparative Zoology 144(2):27-60.
- R. R. Reisz - 1972