27 July 2019
More from 1969
More paleontological discoveries were made in 1969 than just Deinonychus, though that is certainly one of the most famous of dinosaurs. A supposed basal was also described during 1969 that turned out to be a little more unique than a basal dinosaur (of course these are unique themselves). Described by J. F. Bonaparte along with another "new reptile" (Andescynodon being the second description, but not the focus of today's discussion) of the Argentinian Triassic, Riojasuchus tenuisceps (Bonaparte 1969) is an ornithosuchid ("bird crocodile") archosaur whose line of descendants include extant alligators and crocodiles. The holotype includes a nearly complete cranium and partial postcranial elements; more than 50% of the postcranial skeleton is preserved. Four total skeletons are known. The skulls average 25 cm (9.8 in) in length. Riojasuchus actually has a similar head to total length ratio compared to its descendants despite the general appearance of having a much shorter skull than alligators and crocodiles. Ornithosuchids, including Riojasuchus' relatives are known to reach approximately 2 m (6.6 ft) in length. Two other genera (with single species) show that there was likely a fairly wide distribution, if not a global distribution, of the ornithosuchids: Venaticosuchus Bonaparte 1971 (known from Argentina also) and Ornithosuchus Newton 1894 (known from Scotland).