Synapsids were the largest terrestrial vertebrates in the Permian period (299 to 251 mya), rivalled only by some large pareiasaurian parareptiles such as Scutosaurus.

Synapsids (Greek, ‘fused arch’), synonymous with theropsids (Greek, ‘beast-face’), are a group of animals that includes mammals and every animal more closely related to mammals than to other living amniotes.

Synapsids are one of the two major groups of vertebrates which evolved from basal amniotes. 'Synapsids' means 'fused arch', and refers to their skulls. The group includes mammals and earlier groups related to mammals.

May 16, 2023 · Synapsids are believed to have descended from the earliest amniotes. Their front teeth are distinct from their back teeth, they have limbs under the body, and they have a temporal fenestra (the temporal aperture on the sides of the skull).

Synapsids are animals which have a single temporal fenestra. This is an opening located on the roof of the skull, which is usually located behind each eye socket. For this reason, synapsids differ from other amniotes by cranial anatomy, related to these temporal fenestrae openings.

Synapsids were present in the Carboniferous Period (about 359 million to 299 million years ago) and are one of the earliest known reptilian groups. They were the dominant… …reptiles of the Mesozoic; and synapsids, a common and varied group of mammal-like reptiles that eventually gave rise to mammals in the Mesozoic.

Synapsids are a group of amniotes that includes mammals and their extinct relatives. They are characterized by a single temporal fenestra, an opening in the skull behind each eye.

Apr 6, 2016 · The synapsids were the first amniotes to diversify and appeared about 320 million years ago, at the middle of the Carboniferous period. These first synapsids were characterized by the presence of only one temporal fenestra behind each orbit through which the jaw muscles pass .

Synapsids were the largest vertebrates during the Permian period. Their special characteristics include differentiated teeth – incisors, molars and canines. Thus, they have versatile feeding behaviour. Their jaw transitioned from a reptile-like to a more mammalian-like feature.

The mammals of today are but one branch of the Synapsida, a great vertebrate group with a 300 million year history.