Pulanesaura

Did You Know?

• Pulanesaura is a medium-sized transitional sauropodiform.
• Phylogenetic analysis resolved its position as either one of the least derived sauropods or as the sister taxon to Sauropoda, depending on the definition used.
• A cladogram from 2020 by Oliver W. M. Rauhut and colleagues shows its position within Massopoda.

Discovery and naming

The remains of Pulanesaura were discovered in 2004 in a small quarry on the farm Spion Kop 932 in the Senekal District of the Free State by paleontologist Matthew Bonnan. Excavation took place between 2004 and 2006, and the material was studied by Blair McPhee as part of his dissertation from 2011 onward. The genus and type species Pulanesaura eocollum were formally described and named in 2015 by Blair W. McPhee, Matthew F. Bonnan, Adam M. Yates, Johann Neveling and Jonah N. Choiniere. The generic name derives from the Sesotho word Pulane, meaning 'rain-maker' or 'rain-bringer', referencing the heavy rain during collection, combined with the feminine Latin suffix saura ('lizard'). The specific name eocollum combines Greek eo ('dawn') and Latin collum ('neck'), alluding to its basal position among sauropods, lacking the elongated neck typical of more derived forms. Pulanesaura was one of eighteen dinosaur taxa described in open-access journals in 2015. The holotype, BP/1/6982, is a front dorsal vertebra missing the tip of the neural spine. Referred material includes two isolated teeth, a middle cervical vertebra, five back vertebral arches, a right dorsal rib, three tail vertebrae, a left clavicle, a distal right humerus, a left ulna, a possible fourth right middle hand bone, three ischia, left and right shinbones, and two hindlimb first claws. These remains are considered conspecific due to close association within an area of three to three and a half meters in fine, stable sandstone, consistent morphology, and no conflicting traits between elements from different individuals. The quarry is located just over a kilometer east-northeast of another dinosaur-rich quarry in a higher stratigraphic position within the probably Sinemurian part of the upper Elliot Formation, which yielded the less advanced sauropodomorphs Aardonyx celestae and the smaller Arcusaurus pereirabdalorum.

Paleoecology

Pulanesaura's posture and skeletal build indicate it was a low browser, unlike the prosauropods it shared its habitat with. Studies suggest it coexisted with other sauropodomorphs in the same formation through niche partitioning. Its flexible neck allowed feeding without frequent body movement, conserving energy—a trait later sauropods would greatly extend. The Upper Elliot Formation environment was a predominantly arid floodplain, with vegetation concentrated around river channels, facilitating coexistence with Aardonyx and Arcusaurus.