Slightly More Hopeful Dinosaurs

Lewisuchus--basalmost ornithischian? (from Ezcurra et al., 2019)

Dear me, it’s been awhile, hasn’t it? My tardiness in keeping this blog going has not been entirely intentional; 2020’s been a year for the records? I only hope it ends on December 31st and doesn’t continue on in some space-time warping extension into December 32nd. Nonetheless, I am motivated today to inform you all about a paper that brings together several topics I’ve written about in years past: silesaurids, Pisanosaurus, and the Triassic Ornithischian Crisis. Below, I will offer the briefest of recaps, but hit those links if you want a more complete picture.

Walk This Way

The right manus of Camarasaurus. Note the columnar arrangement and virtual absence of fingers.

Late last year, I introduced you all to the Lessemsauridae, a group of near-sauropod "prosauropods" that grew unreasonably large—up to 12 tons in Ledumahadi mafube. There’s some disagreement about the posture of these enormous animals: in true, blue Sauropoda, the forelimbs are columnar, the hands are pronated, the weight is bore on the fingertips, and there is a reduction in phalanges and claws. This arrangement is present to some degree even in the earliest true sauropods like Melanorosaurus and Barapasaurus.

They Might Be Giants

Ingentia prima by Jorge Gonzalez

Two recent news stories perked my interest recently—the descriptions of two new non-sauropod sauropodomorphs: Ingentia prima from the Late Triassic of Argentina and Ledumahadi mafube from the Early Jurassic of South Africa. Together, these animals (and two others which I’ll get to) form a clade of non-sauropod sauropodomorphs that achieved gigantism independently from true, blue sauropods, which is intriguing for a number of reasons.