Chroniosaurus (?) (THUg 3308 and PIN 3585/124, Clack and Klembara 2009), apparently dissimilar in appearance (judging by the figures) and if so, worthy of its own generic name. ~25 cm in preserved length.
Distinct from the holotype, the naris and internarial fenestra were smaller. The jawline was convex ventrally. The orbit was taller rand raised above the rostral margin. The quadrate leaned further anteriorly. The mandible was shallower. The vomer teeth were long and nail-like.
Distinct from Solenodosaurus, each vertebra was composed of three unfused elements, the neural arch, pleurocentrum and intercentrum in proportions resembling those of pre-reptiles (primitive tetrapods), like Proterogyrinus. This is a reversal and likely a product of the smaller size of chroniosuchians. The first four caudal vertebrae included bent-back ribs that all terminated at the fifth caudal.
The interclavicle was larger. Distinct fromLimnoscelis., but similar to Solenodonsaurus, the humerus had a simple shape, narrow proximally, wide distally.
The ilium had an elongated posterior process and a minor anterior process, as in Limnoscelis. The tarsus was poorly ossified and composed of round elements, all suggestive of an entirely aquatic, bottom-dweller lifestyle.