Thursday, December 9, 2010

Simosuchus - JVP Memoir 10


Those of us who have payed any attention to the evolutionary history of crocodilians cringe when we hear them referred to as "living fossils". With the release of the new Memoir from the Society of Vertebrate Paleontology, this phrase is being thrown a round a lot. I generally detest the use of phrases like "living fossil" or "missing link" for many reasons. One article from the BBC was particularly hard to read, with statements like the following, making it sound like it is breaking news that crocs have a diverse evolutionary history.

"Yet contrary to popular belief, scientists now suggest that the basic body structure of crocodiles, alligators and ghariels evolved from a diverse group of prehistoric reptiles with different body shapes." - Ella Davies, BBC News 


Even the press release from the Society of Vertebrate Paleontology had me worried for a moment. But I shouldn't allow misnomers to distract from the real news. The new Memoir, focusing on the pug-nosed Simosuchus, promises a great overview of crocodylimform anatomy.

'As strange as Simosuchus was, the incredible completeness and preservation of its fossils, coupled with an equally impressive scientific investigation, have yielded one of the most comprehensive volumes of crocodyliform anatomy ever to be published. “Very few crocodyliforms – even those alive today – have been subjected to this level of analysis,” said Brochu. “This reference is going to be used for decades.”' - SVP press release

I will post a more thorough description of Simosuchus and the new Memoir once I have received it in the mail.

Citation:
D. W. Krause and N. J. Kley (eds.), Simosuchus clarki (Crocodyliformes: Notosuchia) from the Late Cretaceous of Madagascar. Society of Vertebrate Paleontology Memoir 10. Journal of Vertebrate Paleontology 30(6, Supplement).

Friday, December 3, 2010

Baurusuchus

Restoration of Baurusuchus salgadoensis sp. nov. from Carvalho et al., 2005 (art by Deverson da Silva)
Meaning: "Bauru crocodile", from the Bauru Group
Species: B. pachecoi Price, 1945; B. salgadoensis Carvalho et al., 2005; and B. albertoi Nascimento and Zaher, 2010
Nominal Author: Price, 1945
Age: Late Cretaceous
Location: Brazil
Physical Characteristics: approx. 3.5 to 4 meters in length, cursorial predator


Monday, November 15, 2010

Hi!

Time seems to have gotten away from me once again, but not without reason. I left my job at the end of October, so I have been dealing with that transition. I left for a number of reasons, but most importantly is that I plan to return to school. I will be taking classes at the University of Maryland this spring as I prepare for and take the GRE, apply to graduate programs, and otherwise prepare for grad school. That has been the good distraction. Unfortunately, at the beginning of October, someone very close to me was diagnosed with a massive brain tumor, so the vast majority of my attention has been focused on him. He had surgery on November 2nd to remove the tumor. Thankfully, he is recovering wonderfully.

Despite all of these goings-on, this blog and my favorite clade have still been on my mind. I will update soon with a featured genus/species, but I also have a few other new ideas for posts including guest posts and museum profiles with a focus on their representation of crurotarsans.

In the mean time, I will leave you with this. I've been cleaning out my office and came across some old things from high school, including a bunch of articles I had clipped from newspapers and magazines on all things paleontological. The one that really caught my eye was from the Fall 2004 issue of National Parks magazine about fossils in national parks and the Paleontological Resource Preservation Act. The article focused heavily on Petrified Forest NP, with these two great pictures to illustrate that the park has more than just a bunch of petrified trees.

"True to their prehistoric focus, Arizona's Petrified Forest National Park boasts a full Postosuchus skeleton mold."
"Finds like this crocodile-like Phytosaur offer keys to understanding Petrified Forest National Park's natural and cultural resources, and unraveling the mysterious landscape that once existed here."

Thursday, October 21, 2010

What's scarier than a rauisuchian?


So, how do you celebrate Halloween? This is my pumpkin from last year - an attempt at Postosuchus. I'd say I did a pretty good job, considering I was working with a pumpkin. Some of the teeth may be a little off, but I think I got all of the fenestrae right. I'm thinking I might have to do Poposaurus this year, but I'm open to suggestions.

Monday, October 18, 2010

SVP Annual Meeting 2010 - Evening Events and Final Stats

This year's meeting turned out to be the largest meeting on record at 1,190 attendees and at last count 761 abstracts submitted, the previous record holder being Austin, Texas in 2007. The 28th Annual Benefit Auction and Social went wonderfully, raising $18,500 dollars for the SVP Education and Research Fund. The theme was Star Trek, but we had bets going for the following themes: Lady Gaga, Avatar, Iron Man (and other such super heroes), Alice In Wonderland, and so on.



Although there was no banquet this year, they still held the awards ceremony to a full room. Here are the winners of the two big awards:

Alfred Sherwood Romer Prize
"The Alfred Sherwood Romer Prize recognizes an outstanding scientific contribution in vertebrate paleontology by a predoctoral student. Selection for participation in the Romer Prize Session at the SVP Annual Meeting is based on the scientific value and quality of an abstract summarizing an original research project, and the Romer Prize is awarded on the basis of the scientific value and quality of the oral presentation of that research during the Romer Prize session a the SVP Annual Meeting."
Winner: Jennifer Olori for her presentation on "DEVELOPMENTAL FEATURES OF MICROSAURS (LEPOSPONDYLI), AND CONSEQUENCES FOR THE EVOLUTION OF DEVELOPMENT AND PHYLOGENETIC RELATIONSHIPS WITHIN TETRAPODA"

Romer-Simpson Medal
"The A.S. Romer - G.G. Simpson medal, the society's highest award, is awarded for sustained and outstanding scholarly excellence in the discipline of vertebrate paleontology."
Recipient: Dr. Rinchen Barsbold

Congratulations to all of the award winners!

Sunday, October 17, 2010

SVP Annual Meeting 2010 - Part 3

Tuesday was really the day for crurotarsans, with an entire session dedicated to crocodylomorphs and 14 posters covering a large diversity of the clade. Here's a quick list of them all.
Talks:
  • "Phylogenetic analysis of goniopholidid crocodyliforms of the Morrison Formation" by Eric Allen
  • "The evolution of trematochampsid crocodyliforms in Africa: new evidence from the Middle Cretaceous Galula Formation, Southwestern Tanzania" by J. Sertich and P. O'Connor
  • "A new baurusuchid (Crocodyliformes, Sebecosuchia) from the Bauru Group, Late Cretaceous of Minas Gerais, Brazil" by F. Montefeltro and M. Langer
  • "A reevaluation of the crocodyliform Acynodon from the Late Cretaceous of Europe" by A. Turner and C. Brochu
  • "New large blunt-snouted dyrosaurid (Mesoeucrocodylia) from the Paleocene of Columbia" by A. Hastings, J. Bloch, and C. Jaramillo
  • "Crocodylians from the Uinta Formation (Middle Eocene, Uintan) of western North America, response to climate change and the origins of Alligator" by C. Brochu and D. Snyder
  • "New material of Mekosuchus inexpectatus (Crocodylia: Mekosuchinae) from the Late Quaternary of New Caledonia, and the phylogenetic relationship of Australasian Cenozoic crocodylians" by S. Salisbury, T. Holt, T. Worthy, C. Sand, and A. Anderson
  • "Atmospheric hypoxia increases bone robusticity in the American Alligator" by T. Owerkowicz, E. Andrade, R. Elsey, K. Middleton, and J. Hicks
  • "Osteohistological analysis of Alligator mississippiensis indicates absense of fibrolamellar bone in crocodylians and confirms determinate growth with first report of external fundamental systems: implications for tetrapod osteohistology" by H. Woodward and J. Horner
  • "Mandibular mechanics of Alligator mississippiensis from beam models to finite element analysis" by L. Porro, D. Reed, J. Lemberg, U. Zapata, and C. Ross
Posters:
  • "Asymmetric skeletal adaptation to a debilitating pathology in the hindlimb of Poposaurus gracilis (Archosauris: Poposauroidea)" by M. Shirley, E. Schachner, and C. Shaw
  • "A metriorhynchid crocodyliform braincase from Northern Chile" by M. Fernandez, A. Paulina Carabajal, Z. Gasparini, Y. Herrera, and G. Chong
  • "Clarification of the skeletal anatomy of phytosaurs based on comparative anatomy and the most complete specimen of Angistorhinus" by M. Stocker
  • "The axial skeleton of Gracilisuchus stipanicicorum: autapomorphic charactersand its phylogenetic information within the context of Crurotarsi" by A. Lecuona
  • "Towards a stable phytosaur taxonomy: distinguishing characteristics between Pseudopalatus and Redondasaurus (Phytosauridae: Pseudopalatinae)" by M. Mancini and A. Hungerbuchler
  • "First occurence of the marine crocodyliform Terminonaris from the Upper Cretaceous (Turonian) of Manitoba" by J. Hatcher and A. Janzic
  • "New occurrence of the long-snouted crocodyliform, Terminonaris cf. t. robusta, from the Woodbine Formation (Cenomanian) of Texas" by T. Adams, M. Polcyn, O. Mateus, D. Winkler, and L. Jacobs
  • "One or two species of the giant crocodylian Deinosuchus?" by D. Schwimmer
  • "Dinosaurs walk tall: a crocodilian trace from the Lance Formation (Upper Cretaceous) of Wyoming" by P. Manning, J. Milan, and P. Falkingham
  • "A unique Eocene crocodylian from the Uinta Basin, Utah" by S. Masters, S. Sandau, D. Burk, and L. Krumenacker
  • "Crocodyliforms from the Early Miocene Domo De Zaza locality of Cuba" by O. Jimenez Vazquez and C. Brochu
  • "The pulmonary anatomy of Alligator mississippiensis: a unideirectional air flow system that foreshadows the avian respiratory system" by R. Sanders and C. Farmer
  • "Chronic exercise does not alter limb bone morphology or microstructure in the American Alligator (Alligator mississippiensis) " by H. Tsai, T. Owerkowicz, K. Felbinger, F. Andrade, and J. Hicks
  • "The nose knows: the effects of nasal cavity anatomy on airflow in alligators" by J. Bourke and L. Witmer
  • "Estimation of crocodilian body form from snout-vent length and tail girth" by G. Hurlburt 

Wednesday, October 13, 2010

SVP Annual Meeting 2010 - Part 2

So, yesterday was a big day for crurotarsans (although Crocodylomrpha was most widely represented) and the Romer Prize Session on Monday also included some very good croc talks.

Romer Prize Session:
For those of you who are not as familiar with SVP "the Alfred Sherwood Romer Prize recognizes an outstanding scientific contribution in vertebrate paleontology by a predoctoral student." The Romer Prize Session is a series of talks held during the meeting in which one speaker is then chosen as the winner of the Aldred Sherwood Romer Prize and the winner is announced at the awards ceremony on the last night of the meeting. Below, I list the talks from the session that were pertinent to the clade Crurotarsi, as well as any notes I had on the talk.
  • "Tooth pressure, niche occupation and the evolution of the cranial ecomorphology of crocodylians." by P. Gignac.
    • discussed how body size is mostly able to explain bite force and that tooth pressure in crocodylians often exceeds the shear stress limit of bone
    • produced a model that was able to predict individual bite force, giving insight into individual variation
  • "Seasonality as a potential source of variation in Alligator cranial evolution." by R. Sadleir
    • This was an excellent talk (partially because epigenetics were discussed) focusing on phenotypic plasticity as affected by seasonality (and aseasonality)
    • studied ranch animals and wild animals from the same breeding population (also was very good at taking into account many other variable that may have also been sources of phenotypic plasticity)
    • showed how seasonal vs aseasonal environments induced large amounts of phenotypic plasticity that may explain some instances of speciation within Alligator
  • "Evolution of salt-water tolerance in the Crocodylia and related crocodylomorphs: new insights from stable isotopes." by P. Wheatley 
    • distribution and phylogeny suggests salt-water tolerance as an ancestral trait in crocodylomorphs, evolving at least as far back as Dyrosauridae + Crocodylia and becoming secondarily lost in alligators and gharials
    • since it is quite reasonable to assume that thalattosuchians were salt-water tolerant, they can be used as a geochemical proxy for salt-water tolerance in fossils (using carbon isotopes to show access to marine food sources and oxygen isotopes to show marine vs. freshwater "drinking")
    • Evidence suggests that dyrosaurids were salt-water tolerant and possibly even pelagic. If they were indeed pelagic, why did dyrosaurids survive the K-T extinction when so many other large taxa living in the same environment went extinct? Perhaps the juveniles were living in a freshwater environment (in fact, an audience member confirmed the presence of juvenile dyrosaurids in freshwater sedimentary environments).
If you ask me, I think both Sadleir and Wheatly are good candidates for the Romer Prize. Other talks of note were Jen Olori's talk on "Developmental featured of Microsaurs (Lepospondyli)", J. Scannella's talk on "Triceratops: A Model Organism for Deciphering Dinosaur Heterochrony" (this was a phenomenal talk, but may not get the Romer Prize because he did not focus enough on his own personal role in the research), and M. Spaulding's talk on "Phylogeny of the Carnivoramorpha". Stay tuned to hear about the winner of the prize.

Monday afternoon also yielded a few more talks on Crurotarsans, including one on a phytosaur, Pseudopalatus (although it was a somewhat poor talk), and a fantastic talk on the phylogenetic position of Thalattosuchia.
  • "Fossil crocodyliforms and turtles from the Early Cretaceous of Northeastern Mali" by Hill et al
  • "The endocranium, inner ear, and pneumatic structure of the Upper Triassic phytosaur Pseudopalatus pristinus" by Smith et al
  • "Thy phylogenetic position of Thalattosuchia (Crocodylomorpha) and the importance of outgroup choice" by Eric Wilberg
  • "Opportunism, acoustics and mass: exaptation and patterns of middle-ear expansion in Archosauria" by Dave Dufeau and Larry Witmer
More on Tuesday talks and the auction later.

Happy National Fossil Day!

Today is the first ever National Fossil Day, as a part of Earth Science Week. The National Park Service and American Geological Institute have partnered to host this great event.



The stated mission of the event is such: National Fossil Day is a celebration organized by the National Park Service to promote public awareness and stewardship of fossils, as well as to foster a greater appreciation of their scientific and educational values.

I think we can all appreciate the importance of this mission. Please, check out the website (link above) to learn more about the goals and events surrounding National Fossil Day.

Tuesday, October 12, 2010

SVP Annual Meeting 2010 - Part 1

The annual meeting of the Society of Vertebrate Paleontology has been great so far. Pittsburgh is a gorgeous city, with the David L. Lawrence Convention Center overlooking the Allegany River, and the weather has been perfect.

The representation of Crurotarsi at the meeting has started out slow. On Saturday evening, there was a get together of croc workers (mostly Chris Brochu and students) that I attended, but being held in a bar, little discussion of crocs actually took place. Sunday had just about the same amount of crurotarsan content, with only two posters (although quite excellent posters) discussing vertebrates of the Chinle Formation (Petrified Forest area, Arizona):
  • "A new vertebrate fossil locality in the upper Triassic Chinle Formation of Northeastern Arizona" by J. Weinbaum and J. Martz
  • "Understanding and utilizing detailed biostratigraphic data to characterize Late Triassic faunal change: examples from western North America" by J. Martz and W. Parker
Sunday evening was the welcome reception at the Carnegie Museum, which I believe illustrates my reason for naming this blog "Forgotten Archosaurs" quite well. The showcase exhibit of the museum that night was Dinosaurs in Their Time, the Mesozoic hall. After you pass Herrerasaurus to enter the hall, you are greeted by none other than Redondasaurus (shown below).


There are two other skulls of crurotarsans and a shale slab with a squished thalattosuchian to be found in the entire hall. And so, a clade that so dominated the landscape and overshadowed the dinosaurs for the first 50 million years of the Mesozoic and still retained quite a presence (especially in the marine realm as Thalattosuchia and Dyrosauridae) for the remainder of the era, is represented by only 4 species and only one full mounted display, in a hall called Dinosaurs in Their Time. So maybe they aren't entirely forgotten, but "incredibly unappreciated archosaurs" doesn't sound as catchy. And at least the Nile croc got a cool display in the Cenozoic hall (aka. the Mammal Hall...).

Friday, October 8, 2010

Society of Vertebrate Paleontology Annual Meeting 2010

Tomorrow, I depart for the 70th Anniversary Meeting of the Society of Vertebrate Paleontology, held October 10th through the 13th at the David L. Lawrence Convention Center & Westin Convention Center in downtown Pittsburgh, Pennsylvania (USA). This year's meeting is being hosted by the Carnegie Museum of Natural History, which is excited to show off its recently renovated Mesozoic gallery, Dinosaurs in their Time, at the welcome reception Sunday night.


This year's logo features Fedexia striegeli, a tremotopid amphibian from the Late Pennsylvanian of Western Pennsylvania. Fedexia was only just recently published by Carnegie Museum paleontologists in the museum's publication Annals of Carnegie Museum (Berman et al 2010).

As usual, this years talks look like they will be dominated by dinosaurs and mammals, but Tuesday will be the day for Crurotarsans, with an entire afternoon session dedicated to them. I will be posting all that I can about all the new insights into our favorite archosaurs, as well as any other interesting happenings at the meeting, but I do take SVP's embargo policy very seriously. Stay tuned. I am very excited for the meeting and I hope you are too! I hope to see you there!

Monday, October 4, 2010

Wrong side of the Archosaur tree, but still a great cause

You probably already know, but October is Breast Cancer Awareness Month. My grandmother died two years ago of breast cancer that metastasized to her liver and I live in a cancer cluster (over a dozen women in my neighborhood have been diagnosed in the past few years), so this is something close to my heart.


Over at the blog ART Evolved, they have found a unique way to make a difference. For the whole month of October, they are hosting the Pink Dinosaur Fundraiser for Cancer Research. There are two ways to participate: 1.) Go directly to the event page and donate or 2.) send in a picture of a pink dinosaur. For each dino they receive, they will donate $1. I've already sent in two:

 
Adult Triceratops (formerly Torosaurus)



Leptoceratops




Sunday, October 3, 2010

The Gharial

Male Gharial, sporting a large ghara

Species: Gavialis gangeticus (extant) and Siwaliks Gavialis (extinct)
Meaning: derived from Hindi "ghariyal"
Age: Pliocene to now
Location: India and Nepal
Physical Characteristics: up to 6 meters in length, longirostrine (although snouts become shorter and thicker with age) piscivores, possessing laterally flattened tails and webbed hind feet. Males possess "ghara" - a bulbous growth on the tip of the snout - for which they are named.


Thursday, September 16, 2010

The 50 Most Fascinating Blogs on Fossils

The word is spreading. Forgotten Archosaurs made it onto the list of The 50 Most Fascinating Blogs on Fossils on onlinecolleges.org. The blog is #12 under "Paleontology and Geology Blogs". There are a lot of other great blogs on the list, so check it out.

Friday, September 3, 2010

Jurassic Phytosaur

Many of you have probably already heard, especially if you read Chinleana, that there is a paper out suggesting that at least one phytosaur - a marine phytosaur - survived into the Jurassic. I am extremely skeptical about this, but I'm aso not dismissing the idea altogether. Currently, the Jurassic (in the marine record) i defined by the first appearance of the ammonoid Psiloceras. The phytosaur discussed in this paper was found in the horizon just below the first appearance of Psiloceras, which I think makes it quite easy to conclude that the phytosaur was Late Triassic in age. But you should certainly have a read for yourself. And as we know, extinction events aren't always the most clean, abrupt events in the geologic record, so it will be interesting to see how this pans out.

Maisch, M. W. & Kapitzke, M. 2010. A presumably marine phytosaur (Reptilia: Archosauria) from the pre-planorbis beds (Hettangian) of England. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen 257: 373–379. DOI: 10.1127/0077-7749/2010/0076

Wednesday, August 25, 2010

Don't Freak Out!

This is still the same blog, I just updated the template.

Let me know what you think. Do you like the new layout? Should I go back to the old one?

Two New Neosuchians from the Mesozoic of Europe

Cau, A. and F. Fanti. 2010. "The oldest known metriorhynchid crocodylian from the Middle Jurassic of North-eastern Italy: Neptunidraco ammoniticus gen. et sp. nov." Gondwana Research. DOI: 10.1016/j.gr.2010.07.007


Abstract:
Metriorhynchidae is a clade of marine-adapted crocodilians known from several Middle Jurassic–Early Cretaceous specimens collected predominantly in South America and Europe, but poorly known in the northern margin of Gondwana. The “Portomaggiore crocodile” is the most complete specimen of an Italian metriorhynchid to date: it consists of a partial skeleton that has been provisionally referred to an unnamed species of Late Jurassic Metriorhynchus or Geosaurus. The specimen is preserved in the reddish, nodular limestone of the Rosso Ammonitico Veronese Formation (Bajocian–Tithonian); new data on microfossil associations constrain the age of the metriorhynchid to the late Bajocian–earliest Bathonian. On the basis of cranial synapomorphies, the “Portomaggiore crocodile” falls as the closest sister-taxon of the Late Jurassic– Early Cretaceous geosaurines, and is referred to Neptunidraco ammoniticus gen. et sp. nov. It is unique among Middle Jurassic metriorhynchids in showing an incipient streamlining of the skull, shared with Late Jurassic and Cretaceous taxa. Since Neptunidraco is the oldest known member of Metriorhynchidae, its phylogenetic position supports the hypothesis that the timing of the initial metriorhynchid and geosaurine diversifications should start in the Bajocian.


Martin, E. J., M. Rabi, and Z. Csiki. 2010. "Survival of Theriosuchus (Mesoeucrocodylia: Atoposauridae) in a Late Cretaceous archipelago: a new species from the Maastrichtian of Romania." Naturwissenschaften. DOI: 10.1007/s00114-010-0702-y

Abstract:
Small terrestrial non-eusuchian mesoeucrocodylians are common components of Cretaceous assemblages of Gondwanan provinces with notosuchians and araripesuchids as flagship taxa in South America, Africa and Madagascar, well into the Late Cretaceous. On the other hand, these are exceedingly rare in Laurasian landmasses during the Late Cretaceous. Small terrestrial mesoeucrocodylians from Europe were often referred to the genus Theriosuchus, a taxon with stratigraphic range extending from the Late Jurassic to the late Early Cretaceous. Theriosuchus is abundantly reported from various European localities, although Asiatic and possibly North American members are also known. It has often been closely associated with the first modern crocodilians, members of the Eusuchia, because of the presence of procoelous vertebrae, a widespread key character diagnosing the Eusuchia. Nevertheless, the relationships of Theriosuchus have not been explored in detail although one species, Theriosuchus pusillus, has been extensively described and referred in numerous works. Here, we describe a new basal mesoeucrocodylian, Theriosuchus sympiestodon sp. nov. from the Maastrichtian of the Haţeg Basin, Romania, suggesting a large temporal gap (about 58 myr) in the fossil record of the genus. Inclusion of the new taxon, along with Theriosuchus guimarotae, in a phylogenetic analysis confirms its referral to the genus Theriosuchus, within a monophyletic atoposaurid clade. Although phylogenetic resolution within this clade is still poor, the new taxon appears, on morphological grounds, to be most closely related to T. pusillus. The relationships of Atoposauridae within Mesoeucrocodylia and especially to Neosuchia are discussed in light of the results of the present contribution as well as from recent work. Our results raise the possibility that Atoposauridae might not be regarded as a derived neosuchian clade anymore, although further investigation of the neosuchian interrelationships is needed. Reports of isolated teeth referable to a closely related taxon from the Upper Cretaceous of Romania and France, together with the presence of Doratodon and Ischyrochampsa, indicate a previously unsuspected diverse assemblage of non-eusuchian mesoeucrocodylians in the Late Cretaceous European archipelago.

Thursday, August 12, 2010

A Little Recognition

My lovely blog has just been recognized by the University of Maryland's College Park Scholars Program (CPSP) in a short news blurb. I participated in the program in my first two years at the university but stayed involved for all four years of my undergraduate career.



I certainly do credit Drs. Holtz and Merck for my knowledge of Crurotarsans and website development (even though blogger.com does most of the work as far as the website itself, I can do a lot more with my knowledge of html code). I am well known for my my praise of Dr. Merck, Dr. Holtz, and the Earth, Life, & Time program (example), so I wont start again here, but the College Park Scholars Program deserves a lot of credit too for the quality it adds to both life and education at the University of Maryland. So thanks CPSP!!! Keep up the good work and your students will follow.

Dr. Merck (left) and Dr. Holtz (right)

Wednesday, August 11, 2010

Crocs in the News

Hope for the Future of Crurotarsan Archosaurs:
2600 Baby Saltwater Crocodiles Born

No Death Roll for these Crocs:
Ancient Crocs May Have Chewed Like Mammals

Pakasuchus kapilimai

Sunday, July 18, 2010

Pristichampsus

Alright, breaking out of the Triassic, and clear into the Cenozoic, I'm back with Pristichampsus:

Pristichampsus illustrated by Robert Bakker

Meaning: "saw crocodile"
Species: P. hengdongensis and P. rollinati (after Rossmann 1998)
Nominal Author: Gervais 1853
Age: Paleocene and Eocene
Location: Asia, Europe, and North America
Physical Characteristics: approx. 3 meters long, carnivorous eusuchian with long limbs (cursorial, capable of galloping and facultative bipedalism) and a round tail


Wednesday, July 7, 2010

SVP

This is just a reminder: today is the last day to get the early registration rate and it is the deadline for field trip and workshop registration for the 70th Annual Meeting of the Society of Vertebrate Paleontology. So hurry over to the website and get yourself registered. Regular rregistration last through September 8th. The meeting will be held October 10 - 13 at the David L. Lawrence Convention Center & Westin Convention Center in Pittsburgh, PA, USA. Hope to see you there! Also note: I've posted a poll for SVP attendance.

P.S. I promise to get back to posts of higher quality very soon. Honestly.

Sunday, June 27, 2010

Typothorax

Sorry for the long hiatus, but you all know how busy life can get. I'm back though, with a post on Typothorax.

(from the cover of JVP, Volume 30, Number 3. By Matthew Celeskey)

Meaning: "mark made by a blow to the breastplate"
Species: T. coccinarium (Cope 1875), T. antiquum (Lucas et al 2002)
Nominal Author: Cope 1875
Age:  Late Triassic
Location: North America - Arizona (Chinle Formation), New Mexico and Texas (Bull Canyon Formation, Dockum Group)
Physical Characteristics: no more than 3 meters in length, with a tail equalling approximately half the body length and a mass of about 100 kg. Typothorax possessed the typical aetosaur armor with enlarged spike on its neck.


Tuesday, May 25, 2010

A Call for Feet

I'm taking a break this week from my featured species post because life is just too busy. In the mean time, I would like to ask for a little help from you all. I am looking for a good picture of the full, articulated foot and ankle of a crurotarsan. If anyone has a good picture, a paper with a good picture or schematic, or access to a specimen that they can photograph, I would greatly appreciate it if you would contact me. I am an artist in my spare time and as such, I would like to create a logo for the blog (and what better logo than a crurotarsan ankle), but the scientist in me wants to get it as accurate as possible.

Also, there have been several more articles popping up about the Prestosuchus recently found in Brazil. It is the first specimen found with a well preserved hind leg, which should give a lot of insights into how this animal moved and it's phylogenetic relationship to other rauisuchians. The fossil was found in a formation that was once a lake, which may give us some clues as to how Prestosuchus lived.



Lastly, I just got my first mailing about the 70th annual meeting of the Society of Vertebrate Paleontologists.  The meeting will be held in Pittsburgh, Pennsylvania, USA at the Westin Convention Center, October 10th through 13th and is hosted by the Carnegie Museum of Natural History. I hope to see you all there!

Wednesday, May 19, 2010

Geosaurus

Type of Geosaurus giganteus (Von Sommerring 1816)(from Young and Andrade 2009)

(sensu Yound and Andrade 2009)
Meaning: "earth lizard"
Species: G. giganteus (type - von Sommerring 1816 as Lacerta giganteus), G. grandis (Wagner 1858), G. lapparenti (Debelmas and Strannoloubsky 1957), G. carpenteri (Wilkinson et al 2008)
Nominal Author: Cuvier 1824
Age: Late Jurassic to Early Cretaceous
Location: Europe (incl. UK and Germany)
Physical Characteristics: a short snouted marine crocodyliform (thalattosuchia)

Friday, May 14, 2010

No Love for the Paleogene

The results for the second poll are in. So, which Crurotarsan time period was your favorite? No surprise, it was the Triassic. But the rest of the results were a little more interesting. In second place was the Cretaceous Period (which I am going to somehow blame on Tom Holtz). Really surprising was the time period in 3rd place, which wasn't actually a period, but an era, and it wasn't even a Crurotarsan era. It was the Paleozoic! I'm just wondering, who comes to a Crurotarsan themed blog and votes in a poll for an option that starts with the phrase "screw Crurotarsans"? Well, we're glad you're here anyway, even if we're not sure why. The Jurassic came in 4th place with a measly 5%. Tied for 5th were the Neogene and anything-but-the-Phanerozoic (same question to these people: you do realize this is a blog about critters from the Phanerozoic?). And for whatever reason, the Paleogene got no votes. NONE! Nada. Niet.


Well, I'm pretty perplexed at some of you, but as I said, I'm glad to have you anyway. Stay tuned for more polls and more hot Crurotarsan action!

Wednesday, May 12, 2010

Nearly Complete Prestosuchus Found



I got the word yesterday from Marcel Lacerda of the Universidade Federal do Rio Grande do Sul, Instituto de Geociências, that a nearly complete skeleton of Prestosuchus has recently been found in southern Brazil.  You can read the original article (in Portuguese) here, or, I have made my attempt at translating it into English below.

"Brazilian researchers found the fossil of a prehistoric predator in excellent condition near a town 260 km from Porto Alegre. A reptile, classified as Prestosuchus chiniquensis, lived 240 million years ago, before the appearance of the dinosaurs. It is the most well preserved fossil of the major predator of the Middle Triassic. A paleontologist of the Universidade Luterana do Brasil (Ulbra) Sergio Cabreira and a biologist, Lucio Roberto da Silva combed a ravine where two fossil vertebrae had already been found; they then saw the should blade of a Prestosuchus recently uncovered by the rains. After they removed some of the sediment, they uncovered parts of the skull, forearms, and chest.

Prestosuchus belonged to a group of basal archosaurs - predators that preceded the dinosaurs, pterosaurs, and crocodiles in the tree of evolution. Morphologically, the fossil is more similar to an alligator; it walked on all fours, had a long tail, and a long snout. But it walked upright. Researchers estimate that it weighed 1 ton and was about 7 meters long and 1.5 meters tall."

Not the most scientific of articles (especially the part about Prestosuchus living BEFORE dinosaurs appeared), but a good briefing on such a recent discovery. Prestosuchus is probably my favorite extinct animal (and I'm guessing you're all fans as well), so it will be very exciting to see this develop. Would you just look at that beautiful skeleton!


Thank you Marcel! I hope my translation was fairly accurate.

Also, don't forget to cast your vote for your favorite Crurotarsan time period! The poll closes early Friday morning.

Monday, May 10, 2010

Arizonasaurus

Arizonasaurus babbitti. Scale bar = 0.5 meters. (Nesbitt 2005)

Meaning: "Arizona lizard"
Species: A. babbitti
Nominal Author: Welles 1947
Age: early Middle Triassic (Anisian - 240 Ma)
Location: Arizona, southwestern USA (Moenkopi Formation)
Physical Characteristics: a large (3+ meters) sail-backed predator (Rauisuchian)

Friday, May 7, 2010

And the winner is...

The poll for "which name do you prefer?" is closed and the results are in. Crurotarsi wins by a landslide with 72% of the votes, followed up by Pseudosuchia with a modest 22%, and Crocodylotarsi with a mere 6%. Obviously, this doesn't resolve any of the issues in the nomenclature, but it gives me a nice view of the readership. Surely, these results are biased. How many people who dislike the term "Crurotarsi" are going to come to a blog with such a name in the title? But clearly there are enough, since 28% of the votes were anti-Crurotarsi. Although the results of this poll may show a bias, I feel a review of the literature may reveal similar skewing in favor of "Crurotarsi", but we shall see.



In other news, I arrived home on Wednesday, after a Cinco de Mayo get together with 2 of my favorite Paleontologists, to a wonderful sight. In my front hallway was a book-shaped package from Amazon and inside was my copy of Triassic Life on Land: The Great Transition by H-D Seus and Nicholas Fraser.



It came out at the end of last month and I have been dying to get my hands on a copy. I have only had the time to browse through it, but it looks pretty Trias-tastic. It is definitely more technical than Fraser's previous book Dawn of the Dinosaurs: Life in the Triassic, without all the pretty paintings by Douglas Henderson, but with the benefit of more up-to-date information.

FYI, if any of you buy one of the above books (or any Amazon product linked to on this website, like on the Resources page) from a link on this website, I get a small portion of the sale. So start buying some Triassic literature and support your favorite crurotarsan-themed blog!

Tuesday, May 4, 2010

Rutiodon


Meaning: "wrinkle tooth"
Species: R. carolinensis, R. manhattanensis (?)
Nominal Author: Emmons 1856
Age: Middle Carnian (Triassic)
Location: Eastern US (North Carolina, possibly New Jersey and Pennsylvania)
Physical Characteristics: Piscivorous phytosaur of 3 to 8 meters in length with a gavial-like long, slender snout. Skull can be identified by slight posterior depression of the supratemporal fenestra and homodont dentition. Nares are positioned at the highest point on the skull.

Friday, April 30, 2010

By the way...


I don't know about you, but I love the Arbor Day Foundation. Now, there is the Mach`s Grün! effort, which has the Arbor Day Foundation plant a tree in Plumas National Forest in Northern California whenever someone posts the above link on their blog or website. I'm all about helping the environment, especially forests, and while I'd prefer to put more money into protecting existing forests, planting new trees is an excellent cause as well.

In other news, you may have noticed that I finished the post on Desmatosuchus, added a poll, and added an About page. If you haven't, check them out!

Sunday, April 25, 2010

Desmatosuchus


Meaning: "link crocodile"
Species: "D." haplocerus, D. spurensis, and D. smalli
Nominal Author: Case 1920
Age: Carnian(?)/ Norian (Late Triassic)
Location: Southwestern US (Texas, New Mexico, Arizona - Chinle and Dockum strata)
Physical Characteristics: Large (4+ meters) aetosaur. Typical aetosaur characteristics include an armored carapce arranged in four columns along the dorsal side, an upturned “pig-nosed” premaxilla, and stout forelimbs. Desmatosuchus is distinct in having large recurved spines on the posterior part of its neck.

Thursday, April 22, 2010

In Honor of Earth Day

Since it's earth day, I thought I would talk about an extant species of Crurotarsi, the America alligator (Alligator mississipiensis), and its importance to the everglades ecosystem.

The American alligator is considered a keystone species, meaning that it plays a vital role in its ecosystem (and can be used as an indicator of that ecosystem's health). The major contribution of the alligator is its "gator hole". Alligators dig their holes as refuges during the dry season, but these hole don't just serve the alligator. The gator holes are vital sources of water for fish, birds, turtles, and many other species, and they end up being a convenient source of food for the alligators. Alligators also provide a service through the building of their nests. Several turtle species rely on these nests to lay their own eggs.

The American alligator was put on the endangered species list in 1967. They were killed for their skin and also because they were considered a nuisance. However, after laws were passed to protect the alligators, they rebounded and were removed from the endangered species list in 1987.


Everglades NP - The American Alligator in Depth
The Keystone Species Concept

Wednesday, April 21, 2010

1 week and counting.

So, yesterday marked 1 week for this blog and I am pretty pleased with the way things have been going. We've had visitors from over 12 states, 8 countries, and 4 continents! On that note, there are just a few people I want to thank for helping to get this blog going. First, David Tana over at Superoceras for inspiring me to start the blog. Second, Dr. Tom Holtz for first getting the word out on facebook. And last but not least, Bill Parker for spreading the word on his blog Chinleana. Thanks everyone!

As I have mentioned, I will be posting a weekly feature on a particular species each week (Prestosuchus was the first), but I will also intersperse posts about other issues surrounding Crurotarsi. I have been slowly adding to the Pictures and Resources pages. I am also working on an About page, and if I see there is a need, I will include some sort of glossary type page to explain some of the more technical paleo-lingo for the novice.

It's only been a week, so bear with me as the blog grows and evolves. I think we're off to a good start, but there's much more to come.

Sunday, April 18, 2010

Prestosuchus

Meaning: "Presto's Crocodile"
Species: P. chiniquensis and P. loricatus
Nominal Author: Huene 1942
Age: Ladinian - Carnian (Middle/Late Triassic)
Location: Santa Maria Formation, Brazil
Physical Characteristics: Large (~5 meters) quadrupedal predator with an erect posture

Thursday, April 15, 2010

CAMP and the Triassic-Jurassic Extinction


A new paper published in the Proceedings of the National Academy of Sciences this week (online as of March 22) suggests that it was indeed the volcanism associated with CAMP (the Central Atlantic Magmatic Province) that was directly responsible for the end-Triassic extinction (and therefor, the extinction of many major groups of Crurotarsans). The findings show that the carbon isotope excursion (CIE) of the extinction occured simultaneously with the erruption of CAMP. The close relationship between the extinction, the eruptions, and the CIE is the strongest evidence yet presented for a volcanic cause for the Triassic-Jurassic extinction. Below, I list two news articles that discuss the paper. The full citation for the paper can be found on the resources page of this site.

Wired: Dinosaurs Rode Volcanic Armageddon to Victory
Discovery News: How Dinos Ruled The World

Wednesday, April 14, 2010

Gotta Love Taxonomy

I came across this (The 10 Lamest Dinosaur Names) and just wanted to thank Crurotarsan paleontologists for not getting too carried away in the naming of their discoveries.

But there is one Rauisuchian that I have to make fun of a little:

Poposaurus

"Oh hell no! Here come da poposaurus! Stash the dope, yo!"


A Few Notes While I Get Myself Organized

As many of you know, there is a lot of information out there on Crurotarsans, so as I begin to wade through all that, I'd just like to say a few things.

As you may have noticed, I have added a page for pictures and a page for resources (academic papers, books, etc). They are in their very early stages of development, so bear with me, and if you wish to contribute, feel free.

Just a warning: the majority of my posts will focus on the Triassic representatives of our starring clade. Afterall, the Triassic was when they were at their most numerous and diverse. But for those of you who prefer the post-Triassic crocs, you will not be forgotten. I could never leave out such cool critters like Thalattosuchia and Pristichampsus.

I plan on having a few weekly or monthly themed posts. For instance "The Weekly Crurotarsan" where I feature a single species. I'm not sure about the title, but you get the idea. "Crurotarsan" doesn't always flow off the tounge so nicely. I tend to trip over the 'r's myself. But what would replace it? "Crurotarsan" doesn't lend itself to a nickname very easlily, unlike say "Dinosaur" which is so readily shortend to "dino". I could always use "croc", but I feel like that should be reserved strictly for Crocodylomorphs... but I digress.

Just sit back, relax, and prepare yourselves for some awesome extinct archosaur action.

Tuesday, April 13, 2010

Welcome. An Intro to Crurotarsi.

Hi everybody!

I present, as my first entry, a brief introduction to the great clade, Crurotarsi.

Crurotarsans are some pretty amazing animals, having occupied almost every major ecological niche during the Triassic Period, a time that lasted almost 50 million years (251 Ma to 201.6 Ma). They still survive today as crocodiles, alligators, and their relatives but are nowhere near as diverse and impressive as their ancestors. Named by Paul Sereno in 1991, Crurotarsi means "cross-ankles" based on the way their ankles articulate compared to their sister taxon, Avemetatarsalia (Dinosaurs, Pterosaurs, etc). Although the taxonomy is still disputed some of the groups that make up this clade include Phytosaurs, Aetosaurs, Rauisuchians, Poposaurids, and Crocodylomorphs.