Protoclepsydrops is an extinct genus of early synapsids, found in Joggins, Nova Scotia.[1] The name means 'first Clepsydrops', and refers to it being the predecessor of the other early synapsid Clepsydrops.
| Protoclepsydrops Temporal range: Late Carboniferous, | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Synapsida |
| Clade: | incertae sedis |
| Genus: | †Protoclepsydrops Carroll, 1964 |
| Type species | |
| †Protoclepsydrops haplous Carroll, 1964 | |
Description
Like Archaeothyris, Protoclepsydrops resembled a modern lizard in superficial appearance. However, Protoclepsydrops had primitive vertebrae with tiny neural processes typical of their amniote ancestors. Protoclepsydrops is known from a few vertebrae and some humeri.[2]
Classification
Its skeletal remains indicate that it may have been more closely related to synapsids than to sauropsids, making it a possible stem-mammal. If so, it is the oldest synapsid known, though its status is unconfirmed because its remains are too fragmentary. Protoclepsydrops lived slightly earlier than Archaeothyris.[3]
