October 2, 2008

Pachyrhinosaurus lakustai

11:04 am
  • New Dinosaur: Pachyrhinosaurus lakustai
  • Name Means: Lakusta’s Thick-nosed reptile.
    (Al Lakusta discovered the Pipestone Creek Bonebed where the fossils of this dinosaur were found.)
  • Relations: Ceratopsian
  • Location: Alberta, Canada
  • Age: Late Cretaceous, ~73,000,000 years ago
  • Length: 6 meters, ~20 feet
  • Weight: 1800 kilograms, ~2 tons
  • Info: Pachyrhinosaurus lakustai is known from fossils first discovered more than 30 years ago in a densely packed bonebed in Alberta, Canada. Like the previously known species of Pachyrhinosaurus, P. canadensis, this new species had a thickened mass of bone (or boss) atop its nose as an adult. Unlike P. canadensis, the bosses of P. lakustai are present only in adults—juveniles of the new species were found to have horns like those of other ceratopsians. P. lakustai also differs from P. canadensis in smaller overall size and details of the ornamental spikes and bumps on its frill, according to the summary page of the newly released monograph describing this species.
  • Reference: Currie, P. J., Langston, Jr., W., Tanke, D. H., 2008. A New Horned Dinosaur from an Upper Cretaceous Bone Bed in Alberta. NRC Press. 152pp. ISBN-13 9780660198194.
  • Web coverage:
  • Update (10/3/08): Lawrence Witmer and Ryan Ridgely have made their work on the brain cavity and inner ear of Pachyrhinosaurus lakustai available online. From their “common language summary”:

    Indeed, the most remarkable aspect of the brain structure of Pachyrhinosaurus is how small and primitive it must have been…Despite the cranial ornaments suggestive of perhaps elaborate behavioral displays and other evidence suggesting herding behavior or even migration, the behaviors of Pachyrhinosaurus were probably relatively simple, stereotyped, and instinctual.

—Matt Celeskey.

September 30, 2008

Aerosteon riocoloradensis

12:14 am
  • New Dinosaur: Aerosteon riocoloradensis
  • Name Means: Air bones from the Rio Colorado
  • Relations: Basal (allosauroid?) tetanuran theropod
  • Size: 9 meters/30 feet long
  • Location: Cañadon Amarillo, Argentina
  • Age: Late Cretaceous, ~84,000,000 years ago
  • Info:

    Key to the pneumatic features reported in Aerosteon riocoloradensis
    from Sereno et al. 2008. See here for detailed caption.

  • The fossilized bones of Aerosteon are extensively pneumatized— that is, riddled with hollow spaces. In life, some of these spaces would have housed air sacs that helped maintain a steady flow of air through the dinosaur’s rigid lungs. Modern birds have inherited this type of respiratory system from their dinosaurian ancestors, who may have developed this distinctive aerated anatomy in order to breathe more efficiently, or lighten their load and keep balance while running on two legs, or as a built-in air-cooling system to keep from overheating. The extreme degree of pneumatization preserved in a relatively primitive theropod like Aerosteon helps researchers pinpoint when specific features of the avian respiratory system first evolved.
  • Reference: Sereno, P. C., Martinez, R. N., Wilson, J. A., Varricchio, D. J., Alcober, O. A., Larsson, H. C. E., 2008. Evidence for Avian Intrathoracic Air Sacs in a New Predatory Dinosaur from Argentina PLoS ONE 3(9): e3303. doi10.1371/journal.pone.0003303.
  • Web coverage:
  • Update 10/6: Matt Wedel reviews the current state of research on dinosaur pneumaticity and raises some criticisms of Sereno et al.’s paper describing Aerosteon in two posts over on SV-POW.

—Matt Celeskey.

September 29, 2008

Critters with great big claws on their fingers

6:45 am

You could almost say, “Critters whose great big claws are their fingers”:

—Matt Celeskey.

May 18, 2008

Embracing the Inner Fish

10:50 am

In this case, mine appears to be a Triassic coelacanth:

The author with a model of Chinlea

This was the scene at The Day Job a couple of weeks back, as we unpacked a sculpture for the newly-opened Triassic exhibit. I happened to be wearing the right shirt for the occasion, and my boss David snapped this picture. The piece I’m holding is a fantastic restoration of the freshwater coelacanth, Chinlea sorenseni, about to snap up a school of Synorichthyes. The fish were sculpted by the talented Gary Staab of Staab Studios for the exhibit.

And here’s how the sculpture looks on display, beneath a cast of an fossil Chinlea skull and some Triassic coelacanth bits from New Mexico. The panel is sandwiched between a petrified lungfish burrow and the reconstructed leaves of the enigmatic plant Sanmiguelia. A reflection from the fishtank of Kirby, a living African lungfish, can be seen in the window:

Chinlea on display in the NMMNHS Triassic Hall

—Matt Celeskey.

May 17, 2008

Dawn of the Dinosaurs: Triassic New Mexico

8:46 am

Today’s the day! Dawn of the Dinosaurs: Triassic New Mexico opens at 9:00 sharp at the New Mexico Museum of Natural History and Science. I (and many other talented staff, volunteers, and contractors) have been working on this exhibit for a couple of years now, and I’m proud (and more than a little exhausted) to say that everyone’s hard work came together beautifully this past week.

I’ll be at the museum for an exhibit poster signing from 9:00 to noon, so if you’re in the vicinity, stop by and say hi.

If you aren’t anywhere near Albuquerque, there’s still a portion of the exhibit tailor-made for you. There hasn’t been any press on this yet, but if you swing by nmstatefossil.org and poke around, you’ll find a wealth of information on New Mexico’s most famous fossil resident, the little dinosaur Coelophysis. The NMMNHS has gotten permission from several authors, publishers, and other museums to distribute much of the primary literature on this Triassic theropod, so digging deep into the site will allow you to access a couple dozen PDFs of technical and popular articles.

The site was put together by Ideum, a fantastic group of interactive developers in Corrales, NM. They also worked with us on an in-hall interactive to interpret our two-ton Coelophysis block from Ghost Ranch:

The NMMNH Coelophysis block with its interpreted interactive

The touchscreen display features a drag-and-zoom viewer that allows visitors to get a detailed look at the block, a series of highlighted features that can be toggled on and off, video segments of the block’s preparator explaining the features in detail, and an overlay showing the death positions of 7 of the more complete Coelophysis preserved in the block. More info about the interactives can be seen at Ideum’s blog and portfolio site.

And some quick pictures from before I dash out the door:

Triassic Amphibian skulls

The skulls of Triassic amphibians. Clockwise from the top: Eocyclotosaurus (cast), Hadrokkosaurus (cast), juvenile and adult Buettneria (fossil), and Mastodonsaurus (cast).

Touchable cast of the aetosaur Typothorax

A touchable bonded-bronze cast of the aetosaur Typothorax coccinarum.

Skulls of phytosaurs (Pseudopalatus buceros) from the Snyder Quarry

Phytosaur skulls (Pseudopalatus buceros) from the Snyder Quarry near Ghost Ranch.

The braincase of the oldest-known mammal, Adelobasileus

The tiny braincase of the earliest-known mammal, Adelobasileus cromptoni.

—Matt Celeskey.