Machimosauridae

Machimosauridae is a diverse group of teleosauroids, phylogenetically defined as "the largest clade within Teleosauroidea containing Machimosaurus hugii, but not Plagiophthalmosuchus gracilirostris and Teleosaurus cadomensis."[1] The members of the Machimosauridae share several unique characters among teleosauroids, which are:[1]

• dorsally oriented external nares
• the premaxillary anterior and anterolateral margins are not sub-vertical and do not extend ventrally
• the premaxilla-maxilla suture is sub-rectangular and slightly interdigitating (most noticeably near the midline)
• no anterolateral expansion of the supratemporal fenestrae
• the postorbital is excluded from the orbit posteroventral margin
• a mostly horizontal pterygoid with a distinct posterolateral angle
• the cultriform process of the basisphenoid is exposed and bifurcates the pterygoids

The phylogenetic relationships of the Machimosauridae were analyzed in a comprehensive analysis of teleosauroid relationships. The results of the analysis are shown below:[1]

Machimosaurids grew in body size and diversified feeding strategies throughout their evolutionary history. Primitive machimosaurids, such as Macrospondylus and Charitomenosuchus, were longirostrine (long-snouted) generalists with body lengths less than 5 m (16 ft) long.[1][3] Machimosaurines originated in the Bathonian stage of the Middle Jurassic and simultaneously underwent a decrease in snout length but an increase in body size with Neosteneosaurus reaching up to 6.6 m (22 ft) long.[1][3] Machimosaurins were the largest teleosauroids, with body lengths up to 7.1 m (23 ft) (Machimosaurus rex), and were durophagous hunters, meaning they fed on hard prey.[1][3]