Paleontology Week in Review: 6/7/14

Sorry about missing the week in review last week-there wasn’t much going on in the world of paleontology. However, the press this week has brought to my attention some amazing fossil finds.

First we’ve got a beautiful discovery of a pterosaur rookery in Xinjiang by Dr. Wang Xiaolin. This week his team released their paper on the discovery, naming the new species Hamipterus tianshanensis.  The sheer amount of fossil bones reveals much-needed, often-sought but seldom-found information on the animal. Not only are there 5 intact eggs, but at least 40 individuals. This number provides information on physical characteristics (the animals are sexually dimorphic in terms of their crest shape), life cycle (pterosaurs are found in almost all stages of growth), and social organization (nests are preserved,  and the sheer amount of nests and individuals suggests a colony not unlike one of seabirds). 

It’s been suggested for decades that pterosaurs were social animals living like birds in large groups, but this time we have an actual flock.   Wang et al classify it as a relative of the famous Pteranodon, one of the earliest members of the family.  Found it the Aptian Cretaceous Turpan-Hami Basin, it was the successor of the more basal pterosaur Dsungaripterus, but was more of a generalist fisher.

Here’s the paper: http://www.cell.com/current-biology/abstract/S0960-9822%2814%2900525-9

Speaking of mass finds, there was a mass find of early Cretaceous Icthyosaurs in Chile. 36 individuals, some of them pregnant, from 4 different species, were found in a single bed at the Torres del Paine National Park.  The find was discovered ten years ago, but only now has the significance and sheer scope been found. Sadly, the paper is not available in a free journal, so precise details are not known to me. However, like the pterosaurs, this suggests a catastrophe, possible a tsunami or volcanic eruption that killed the animals.

The paper http://gsabulletin.gsapubs.org/content/early/2014/05/22/B30964.1.abstract

A new short-snouted crocodilian was found in the Paleocene Cerrejon formation in Colombia by Alexander K. Hastings of the Florida Museum of Natural History, Jonathan I. Bloch of the Geiseltalmuseum of the Martin Luther Universität Halle-Wittenberg, and Carlos A. Amarillo of Smithsonian Tropical Research Institute. Called Anthracosuchus balrogus, it was distinct for it thick, squared scutes that protected its back, bony tuberosities around its eyes, wide-spaced eyes, short, broad snout, and rounded, blunt teeth. Anthracosuchus is a dyrosaur, a family of crocodilians that evolved in the Palaeocene, flourished, then went extinct. The family was better adapted for aquatic lifestyles than their modern counterparts, thriving in the jungles and wetlands of the Palaeogene and eating fish and other aquatic reptiles. The teeth of this animal seem to be adapted for crushing turtle shells. 

At 16-feet long Anthracosuchus dwarfed most of the other animals of the Cerrejon jungle, including its main prey, the 6-foot turtle Carbonemys, and its relatives the small but similarly short-snouted Cerrejonisuchus and common, long-snouted Acherontisuchus. However, it in turn was prey for the largest snake of all-time, the similarly semiaquatic Titanoboa. Titanoboa was twice the length of a modern green anaconda, and fulfilled a similar role as aquatic apex predator.

The paper http://www.tandfonline.com/doi/full/10.1080/08912963.2014.918968#.U5O_xyigzWg

On to dinosaurs-

Hai Xing and his team from multiple institutions in China, Canada, and the UK released their paper this week on a new hadrosaur from Henan, Zhanghenglong yangchengensis. The animal is described as basal, similar to Bactrosaurus, Telmatosaurus, Lophorhothon,  and other ancestors of hadrosaurs.  The find is scanty and disarticulated, but enough of the skull and post-cranial material remain to get a good picture of this browser, it’s evolutionary relationships, and it’s ecological role.  It’s placed as a sister taxon to Nanyangosaurus. 

It’s from the Majiacun Formation, a Santonian age mid-Cretaceous strata discovered relatively recently and with very few fossils. So far, we know that the troodont Xixiasaurus and alverezasaur Xixianykus shared the habitat, and eggs have been found suggesting therizinosaurs also lived in the area.  Hopefully, more of this animal will be found and more animals in this environment will be found.

Here’s the paper http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0098821

Finally, another dinosaur was found, this one from Luxembourg and described by Dominique Delsate from the Musée national d’histoire naturelle de Luxembourg and Martin D. Ezcurra of the Universities of Birmingham and Munich.  It’s a theropod dinosaur from the Hettangian Early Jurassic: a relative of Megapnosaurus and Sarcosaurus.  The material is scanty-teeth and a foot bone. 

The locale, Reckingerwald quarry, is not known for dinosaurs, either-most of the fossils are of marine invertebrates, with a few plesiosaur, ichthyosaur, and cartilaginous fish bones.  It’s the least of the discoveries in terms of material and drama, and the dinosaur has yet to be named, but it’s still a find worth the publicity

You can find the paper here http://popups.ulg.ac.be/1374-8505/index.php?id=4569

Tune in next week for more paleontology news!