Post-natal parental care in a Cretaceous diapsid from northeastern China

Post-natal parental care seems to have evolved numerous times in vertebrates. Among extant amniotes, it is present in crocodilians, birds, and mammals. However, evidence of this behavior is extremely rare in the fossil record and is only reported for two types of dinosaurs, and a varanopid ‘pelycosaur’. Here we report new evidence for post-natal parental care in Philydrosaurus, a choristodere, from the Yixian Formation of western Liaoning Province, China. We review the fossil record of reproduction in choristoderes, and this represents the oldest record of post-natal parental care in diapsids to our knowledge

Pleistocene fossil snake traces on South Africa’s Cape south coast

Snakes form a large, familiar, and distinctive component of the world’s reptile fauna, with a rich body fossil record stretching back to the Jurassic. The sparse, minimal, and questionable evidence of snake traces in the ichnological record is therefore surprising. Extant snakes in southern Africa employ three types of locomotion—rectilinear, sidewinding, and undulatory, all of which result in distinctive, recognizable traces. A site exhibiting convincing evidence of rectilinear motion, probably made by a puff adder, has been identified in Pleistocene aeolianites on South Africa’s Cape south coast. A new ichnogenus and ichnospecies, Anguinichnus linearis, have been erected to describe this trace. A new suite of optically stimulated luminescence (OSL) ages from aeolianites from the De Kelders Cave locality, 1.4 km to the south, suggests that the site dates to ∼93–83 ka. Trace fossil evidence of sidewinding and undulatory motion is more equivocal and open to alternative interpretations