No time to treat this with more than a passing mention, but a letter in today’s Nature presents a new, Middle Triassic silesaurid from Tanzania named Asilisaurus kongwe (“ancient ancestor lizard”). This adds another continent to the known range of the silesaurids, a group of plant-eating proto-dinosaurs previously found in Europe, South America and North America. It also extends the age of this group back 10 million years, which makes it not only the oldest-known silesaurid, but the oldest known reptile on the bird side of the bird-crocodile split.

Neat stuff, and particularly interesting after looking at Eucoelophysis…

For more information:

• The Nature article: Ecologically distinct dinosaurian sister group shows early diversification of Ornithodira
• Figures from the article
• Graphics and information from the research team
• Coverage at Chinleana

Although fossils of the Triassic theropod Coelophysis bauri are by far the most numerous vertebrate remains preserved in blocks from the Whitaker quarry, several other animals are known from the site as well. Many have just been uncovered or described within the past ten years, and in the course of preparing the NMMNH block (and examining other blocks for comparison), several new fossils have come to light. A brief, annotated list of other fauna known from the quarry appears below:

Invertebrates: As mentioned last time, ostracods (Darwinula sp.) and conchostracans (Shipingia) were found in a sandy layer below the bones, remnants of temporary ponding at the site prior to the Coelophysis burial.

Synorichthys chased by Chinlea, sculpted by Gary Staab

Fish: Schaeffer (1967) reported paleonisciform and coelacanth fish in association with Coelophysis at Ghost Ranch. Both were found in the NMMNH block above the invertebrate layer and just below the lowest tetrapod bones: scaly little redfieldiid paleonisciforms, tentatively assigned to Synorichthys, and bits of fin, scale, and skull from the large coelacanth Chinlea sorenseni. As these fish would have been too large to thrive in the type of ephemeral pond indicated by the invertebrates, we posited that floodwaters washed them in to the site from a larger body of water.

Whitakersaurus bermani: This diminutive sphenodontian (my tiny-tuatara-based restoration at the left) is known from pieces of the upper and lower jaw found within 2 centimeters of the edge of the NMMNH block. The largest piece of the holotype, an incomplete right dentary preserving nineteen tooth-positions, is about 5 millimeters long (Heckert et al. 2008).

Drepanosaurs: Harris & Downs (2002) reported the first drepanosaur material from the quarry—a well-preserved (but isolated) shoulder girdle from the block at the Ruth Hall Museum of Paleontology. In a new review of the drepanosaurs, Renesto et al. (2010) assign that shoulder girdle to the genus Drepanosaurus, and describe a partially articulated but generically indeterminate foot on the edge of the NMMNH block (pictured below).

NMMNH P-57651, the foot of a small drepanosaur, preserved portion roughly 5cm long

Vancleavea campi: By far the most complete specimens of this armor-coated reptile are two beautifully articulated skeletons from the Ruth Hall Museum block, recently described by Nesbitt et al. (2009). Remains of a partial, disarticulated skeleton are associated with some characteristic Vancleavea armor in a mostly unprepared fossil removed from the NMMNH block.

Vancleavea sculpture by Phil Bircheff at the Ruth Hall Museum of Paleontology.

Phytosaurs: An ~80cm long phytosaur skull from the Whitaker/Coelophysis quarry (the holotype of Redondasaurus bermani Hunt and Lucas 1993) is housed at the Carnegie Museum. The skull and lower jaws of a juvenile phytosaur were found in the NMMNH block, currently exposed in left lateral/palatal view on a partially prepared jacket removed from the main block (photo below).

NMMNH P-44920, juvenile phytosaur (Redondasaurus?) skull and jaws, left lateral/palatal view. Photo courtesy of Larry Rinehart.

Postosuchus kirkpatricki: The Carnegie Museum of Natural History and the Ruth Hall Museum of Paleontology both have specimens of this rauisuchian on Whitaker/Coelophysis quarry blocks. These were partially figured in Long and Murry (1995, figs 145–146).

Effigia sculpture by Phil Bircheff
at the Ruth Hall Museum of Paleontology.

Effigia okeefeae: The type specimens of this bipedal suchian were recently discovered in jackets pulled from the quarry during the early excavations by the American Museum (Nesbitt & Norell 2006, Nesbitt 2007). A scapula and coracoid found in the NMMNH block might belong to this animal.

Hesperosuchus agilis: One of the best-preserved specimens of this early crocodylomorph is an articulated skull and partial skeleton now at the Carnegie Museum (Clark et al. 2000). Only a few armor scutes are known from the NMMNH block.

To the best of my knowledge, this little bestiary lists pretty much all the non-Coelophysis animals identified from Ghost Ranch Whitaker quarry fossils. All of them, that is, with one interesting exception, noticed while reviewing specimens on other Coelophysis blocks. Its story will make up the bulk of the next post.

Next time: Truly, Coelophysis?
or, The Mysterious Canadian

Previously:
Introduction

• Main Reference: Rinehart, Larry F., Lucas, Spencer G., Heckert, Andrew B., Spielmann, Justin A. and Celeskey, Matthew D., 2009. The Paleobiology of Coelophysis bauri (Cope) from the Upper Triassic (Apachean) Whitaker quarry, New Mexico, with detailed analysis of a single quarry block. New Mexico Museum of Natural History and Science Bulletin 45, 260pp. Abstract [Rich text file]
• Additional References: Clark, James M., Sues, Hans-Dieter and Berman, David S., 2000. A new specimen of Hesperosuchus agilis from the Upper Triasic of New Mexico and the interrelationships of basal crocodylomorph archosaurs. Journal of Vertebrate Paleontology, vol. 20 (4), pp. 683–704. doi: 10.1671/0272-4634(2000)020[0683:ANSOHA]2.0.CO;2
• Harris, Jerald D. and Downs, Alex, 2002. A drepanosaurid pectoral girdle from the Ghost Ranch (Whitaker) Coelophysis quarry (Chinle Group, Rock Point Formation, Rhaetian), New Mexico. Journal of Vertebrate Paleontology, vol. 22 (1), pp. 70–75. doi: 10.1671/0272-4634(2002)022[0070:ADPGFT]2.0.CO;2 [PDF]
• Heckert, Andrew B., Lucas, Spencer G., Rinehart, Larry F. and Hunt, Adrian P., 2008. A new genus and species of sphenodontian from the Ghost Ranch Coelophysis quarry (Upper Triassic: Apachean), Rock Point Formation, New Mexico, USA. Palaeontology, vol. 51, pp. 827–845. doi: 10.1111/j.1475-4983.2008.00786.x [PDF]
• Hunt, Adrian P. and Lucas, Spencer G., 1993. A new phytosaur (Reptilia: Archosauria) genus from the uppermost Triassic of the western United States and its biochronological significance. New Mexico Museum of Natural History and Science Bulletin 3, pp. 193–196.
• Long, Robert A. and Murry, Phillip A., 1995. Late Triassic (Carnian and Norian) tetrapods from the southwestern United States. New Mexico Museum of Natural History and Science Bulletin 4, 254pp. [link to PDF]
• Nesbitt, Sterling J. 2007. The anatomy of Effigia okeeffeae (Archosauria, Suchia), theropod convergence, and the distribution of related taxa. Bulletin of the American Museum of Natural History, vol. 302, pp. 1–84.
• Nesbitt, Sterling J. and Norell, Mark A., 2006. Extreme convergence in the body plans of an early suchian (Archosauria) and ornithomimid dinosaurs (Theropoda). Proceedings of the Royal Society B, vol. 273, no. 1590, pp. 1045–1048. doi: 10.1098/rspb.2005.3426
• Nesbitt, Sterling J., Stocker, Michelle R., Small, Brian J. and Downs, Alex, 2009. The osteology and relationships of Vancleavea campi (Reptilia: Archosauriformes). Zoological Journal of the Linnean Society, vol. 157 (4), pp. 814–864. doi: 0.1111/j.1096-3642.2009.00530.x
• Renesto, Silvio, Spielmann, Justin A., Lucas, Spencer G. and Tarditi Spagnoli, Georgio, 2010. The taxonomy and paleobiology of the Late Triassic (Carnian-Norian: Adamanian-Apachean) drepanosaurs (Diapsida: Archosauromorpha: Drepanosauromorpha). New Mexico Museum of Natural History and Science Bulletin 46, 81pp.
• Schaeffer, Bobb, 1967. Late Triassic fishes from the western United States. Bulletin of the American Museum of Natural History, vol. 135 (6), pp. 285–342.

The NM Friends of Paleontology are meeting Monday, Nov. 17 at 7:00pm at the New Mexico Museum of Natural History and Science. This month’s meeting includes a talk by Larry Rinehart on some of the recent work he’s done on the allometry, growth, dimorphism and population structure of Coelophysis bauri from Ghost Ranch. The NMFOP meetings are free and open to the public.

On Thursday the 20th, geologist David Love and paleontologist Gary Morgan will be giving a talk on a 10 million year old oreodont recently unearthed at the Bosque del Apache Wildlife Refuge. The talk will begin at 3:30pm in the Macey Center auditorium at New Mexico Tech in Socorro (admission $5). More info about this find is online here.

Still, there is definitely some information that has begun to be spread around to members of the media and the public at large. Rather than risk breaking any news that isn’t ready to be broken, I’m going to compile a list of existing press releases, news stories, and other web content that refers more or less directly to information presented during the sessions at this year’s SVP. If anyone is aware of other stories that apply, please let me know and I’ll happily add them to the list:

Presentations released in their entirety:

• Removing Fossil Ribs: The Thread Technique
Amy Davidson

• Growth, allometry, and age/size distribution of the Late Triassic theropod dinosaur Coelophysis bauri: preliminary results
Larry F. Rinehart, Andrew B. Heckert, Spencer G. Lucas, and Matthew D. Celeskey

• Restoration and three-dimensional assembly of a nearly complete, articulated Eocele Protocetid whale skeleton from Pakistan
William Sanders, John Graf, Iyad Salmout, Munir Ul-Haq, and Philip Gingerich

Publications, press releases, and news stories based on or related to presentations:

The abstracts these stories appear to relate to are printed below the links

• Fossil Find May Document Largest Snake
J. Bloch et al.: Vertebrate Faunas from the Paleocene Bogota Formation of Northern Colombia

• The cranial endoskeleton of Tiktaalik roseae
• Ancient Fish Heads for Land
J. Downs et al.: The cranial endoskeleton of Tiktaalik roseae (Tetrapodomorpha, Elpistostegalia)

• Brain structure provides the key to unraveling the function of bizarre dinosaur crests
D. Evans et al.: Endocranial anatomy of lambeosaurine dinosaurs: Implications for cranial crest function and evolution

• Frontal sinuses and head-butting in goats: a finite element analysis
• Head Butting Goats, Part 1
A. Farke, Evolution and function of the supracranial sinuses in ceratopsid dinosaurs and the frontal sinuses in bovid mammals

• How pterosaurs took flight
M. Habib: Skeletal architecture and launch mechanics of pterosaurs

• Reconstructing a Stone Age Embrace
T. Keillor: Challenge: How to excavate, prepare, display and transport delicate articulated fossils found in unconsolidated sand?

• Live birth in the Devonian Period
• World’s oldest mother – Live birth in the Devonian (includes video content)
• Dr. John Long presents the Matterpiscis M. attenboroughi (video)
J. Long and K. Trinajstic: Devonian placoderm embryos and the origins of vertebrate sex

• Dinosaur ‘mummies’ were just thick-skinned
E. Lund et al.: Preservation of dinosaur integumentary impressions in the Upper Cretaceous Kaiparowits Formation, Grand Staircase-Escalante National Monument, southern Utah

• New Haven scientist says he has solved ancient mystery: How did the turtle get its shell? (includes video content)
T. Lyson & W. Joyce: How did the turtle get its shoulder inside its ribcage, or did it?

• A more fearsome saber-toothed cat
V. Naples and K. Spearing: Reconstruction of the forelimb musculature and function in Xenosmilus hodsonae: an atypical scimitar-toothed cat
L. Martin et al.: Cookie-cutter cats; another saber-toothed morphotype

• Impact of increased character sampling on the phylogeny of Cetartiodactyla (Mammalia): combined analysis including fossils
O’Leary et al.: Instability of pivotal fossil clades in cetartiodactylan phylogeny and evolution of the ear region and ankle

Items that showed up on the conference bulletin board that are hard to classify but fascinating to look at nonetheless:

• treeosaur.com

Updated 10/24 from content found by Neil.

• New Amphibian: Gerobatrachus hottoni
• Name means:Hotton’s Elder Frog
• Relations: Amphibamid temnospondyl and stem-batrachian (an early offshoot on the lineage leading to frogs and salamanders)
• Location: Texas, U.S.A.
• Age: Early Permian, ~290,000,000 years ago
• Size: Less than 12cm (5 inches) long
• Info: The three groups of living amphibians (frogs, salamanders, and caecilians) most certainly had their roots in the great amphibian radiations of the Late Paleozoic Era, but the fossil record has provided few clues that help pinpoint their precise ancestry. Gerobatrachus was a small temnospondyl, part of a very successful and numerous group of amphibians in the latter part of the Paleozoic. The remains of Gerobatrachus exhibit a unique mosaic of features in its teeth, ears, limbs, and vertebrae that suggest it may have been close to the origins of both modern frogs and salamanders. Although many researchers have proposed a close relationship between all three groups of living amphibians, a phylogenetic analysis that included Gerobatrachus found that caecilians had their origins in a completely different group of Paleozoic amphibians, the lepospondyls.
• Reference: Anderson, J. S., Reisz, R. R., Scott, D., Fröbisch, N. B., and Sumida, S. S. 2008. A stem batrachian from the Early Permian of Texas and the origin of frogs and salamanders. Nature 453, 515–518 (22 May 2008) | doi:10.1038/nature06865. The article is available for download from the Center for North American Herpetology PDF Library.
• Web coverage:
  • Press Release
  • LiveScience on MSNBC
  • The Dragon’s Tales 1 & 2
  • Palaeoblog
  • El PaleoFreak

• New pterosaur: Raeticodactylus filisurensis
• Name means: (Wing) Finger from the village of Filisur, in Raetia (the old name for the Swiss Canton Grisons, where it was found)
• Relations: Basal pterosaur
• Location: Eastern Switzerland
• Age: Late Triassic, ~203,000,000 years ago
• Material: Nearly complete skull, partial postcrania
• Wingspan: 135cm (~4.5 feet)
• Info: The oldest known pterosaur fossils come from late in the Triassic period, when this finger-winged group of reptiles first took to the skies. Newly-described Raeticodactylus adds to the handful of currently known Triassic pterosaurs. Raeticodactylus sported a unique crest above its nose, a deeply-keeled lower jaw, and a unique combination of teeth—fangs at the front of its mouth with wrinkled enamel on the inside, and crunching teeth further back in its jaws tipped with three to five cusps. Its limbs were long and thin compared to its contemporaries, giving it about twice the wingspan of the most famous Triassic pterosaur, Eudimorphodon ranzii. And, oddly enough, the head of its femur is offset 90° from the shaft, suggesting an upright stance more similar to that of dinosaurs than other pterosaurs.
• Reference: Stecher, R. 2008. A new Triassic pterosaur from Switzerland (Central Austroalpine, Grisons), Raeticodactylus filisurensis gen. et sp. nov. Swiss Journal of Geosciences doi: 10.1007/s00015-008-1252-6.
• Web coverage:
  • Laelaps
  • When Pigs Fly Returns 1 & 2
  • David Hone’s Blog
  • microecos

According to Wikipedia, the WIPP site was chosen, in part, because the salt deposits have remained relatively stable since they precipitated from a receding Permian sea, over 250,000,000 years ago. Presumably, the same stability helped preserve the earliest direct evidence of biological life—nearly four times the age of the previous record holder: traces of protein from 68 million year-old T. rex fossils.

Cellulose microfibers, from the UNC News press release.

Cellulose microfibers were the most abundant biological materials found, although the article tantalizingly mentions that some evidence of ancient DNA was “observed.”

Now a quarter-billion year-old bit of biomass is pretty darn nifty, and since the research is published in April’s issue of Astrobiology it leads to some interesting ideas about the possibility of finding durable bio-molecules preserved in salt deposits on other worlds. But I think there’s far greater potential for speculation here. I mean, we’ve got Paleozoic biology in proximity to low-level radiation. Forget the atom-bomb triggered monster ants of THEM!—imagine a pickled monuran, revivified and grotesquely enlarged by the careless placement of a used radiation suit, leaping out across the desert as it attempts to satisfy 250 million years worth of salt-cured hunger…

New Dinosaur: Glacialsaurus hammeri
Name means: Hammer’s Frozen lizard

Relations: Basal sauropodomorph (prosauropod) dinosaur
Location: Beardmore Glacier region, Antarctica
Age: Early Jurassic, 190,000,000 years ago

Material: Partial right foot and ankle, partial left femur
Est. Length: 8 meters (25 ft) long
Est. Weight: 5 tons

Glacialsaurus hammeri is only the second dinosaur described from the Jurassic of Antarctica, the first being the pompadour-crested theropod Cryolophosaurus ellioti. Although fragmentary, the remains of Glacialsaurus identify it as a prosauropod, one of several types of early long-necked dinosaurs that split off from the sauropodomorph line before true sauropods like Apatosaurus and Camarasaurus evolved. Other fossils found in the same rock formation as Glacialsaurus may come from a true sauropod, suggesting that prosauropods survived alongside their more advanced relatives for a time in the Early Jurassic.

Technical article: Smith, N. D. and Pol, D. 2007. Anatomy of a basal sauropodomorph dinosaur from the Early Jurassic Hanson Formation of Antarctica. Acta Palaeontologica Polonica 52 (4): 657–674. PDF.

Elsewhere on the web:

• Laelaps
• Palaeoblog
• The Dragon’s Tales
• Wired News
• Eurekalert

First up, a fossil claw of the eurypterid (sea scorpion) Jaekelopterus rhenaniae could have come from the largest arthropod that ever lived. The claw, described in Biology Letters, measures 46 cm in length, and presumably was part of a Jaekelopterus individual 2.5 meters (8.2 feet) long. The story has been well-covered by National Geographic News, The Loom, and Palaeoblog.

This week’s issue of the journal Science has a few brief articles on research presented at last month’s Society of Vertebrate Paleontology Annual Meeting. One provocatively titled story, “Did Horny Young Dinosaurs Cause Illusion of Separate Species?”, reports on the work of John Horner, Mark Goodwin, and Holly Woodward, which suggests that the spiky-headed pachycephalosaurs Dracorex hogwartsia and Stygimoloch spinifer might, in fact, be juvenile forms of the knobby domehead Pachycephalosaurus wyomingensis. Update (11/24): Manabu Sakamoto has a summary of Horner et al.’s presentation up at his blog, Raptor’s Nest.

Finally, researchers at the Royal Tyrrell Museum have announced the discovery of a new ceratopsian dinosaur: Eotriceratops xerinsularis (ee-oh-try-SAIR-ah-tops zeer-in-soo-LAIR-iss), the “Dawn Three-horned face from Dry Island (Buffalo Jump Provincial Park)”. This 68,000,000 year old dinosaur is a couple of million years older than Triceratops, and it may be the ancestor of that well-known genus. Eotriceratops and Triceratops shared several features such as large brow horns and a solid frill, but Eotriceratops also possessed some more primitive characteristics than its younger relative, according to this story in the Edmonton Journal. The three-meter-long skull of Eotriceratops (reconstructed in this photo) would seem to put it in the running for the largest head of any terrestrial animal, alongside other ceratopsian contenders such as Torosaurus and Pentaceratops.

Over at Catalogue of Organisms, Christopher has put up an interesting post about recently described bipedal adaptations in an extinct relative of camels, the tylopod Anoplotherium. Well worth a read!