Jon A. Baskin - Texas A&M University-Kingsville

1. This site focuses on Mesozoic archosaurs, especially non-avian dinosaurs, from Texas
   1. Texas non-avian dinosaurs systematics and geologic time.
   2. Trackways
   3. Theropods
   4. Sauropods
   5. Ornithischians
2. For Texas Mesozoic archosaurs, such as pterosaurs, crocodylians, and phytosaurs, which are not dinosaurs, scroll down or click here

3. Some information on Texas marine reptiles which are not archosaurs is also presented.  Scroll down or click here.

4. Bibliography

LONE STAR DINOSAURS

The definitive and necessary reference: Lone Star Dinosaurs by Louis Jacobs. College Station: Texas A& M University Press. 1995. 160p.

The Lone Star dinosaur exhibit sponsored by the Fort Worth Museum of Science and History and the Shuler Museum of Paleontology at Southern Methodist University is based on Dr. Louis Jacobs' book, Lone Star Dinosaurs (1995, Texas A&M University Press), featuring the original artwork of Karen Carr, whose official website is at: www.karencarr.com.

Discover Texas Dinosaurs by Charles E. Finsley.

Product description from Amazon.com: "Go behind the scenes and into the vaults of Texas dinosaur study. Through photos and narrative, many of Texas' most dedicated scientists show you actual specimens of native and nonnative dinosaur material. This book features photos of the fossilized bones of Texas dinosaurs and the dinosaur exhibits in every major museum in Texas."

Oceans Dallas by Louis Jacobs, Michael Polcyn, Kathie Poth, Norm Poth, and Paul Ballou tells the story of rocks and fossils in the Dallas-Fort Worth area during the late Cretaceous.

Texas dinosaurs are also discussed and illustrated on Texas Parks and Wildlife / kids' page.  The dinosaurs of Texas lists them

A list of Texas dinosaurs from Dinodata also lists Texas dinosaurs by formation and provides links to further information.

The archosaurs from North-Central Texas are summarized in Jacobs and Winkler (1998).

Lundelius (1986) includes a summary of Cretaceous fossils from the Balcones Fault trend.

Texas Dinosaurs: Life and Death in the Big Bend -- an exhibit from the Dallas Museum of Nature and Science

North Texas Fossils -- Photographs by Lance Hall of mainly Cretaceous fossils from the Dallas-Fort Worth area.

TEXAS MESOZOIC DINOSAURS

Systematics

Superorder Dinosauria
     Order Saurischia
          Suborder THEROPODA
               Infraorder Herrerasauria
                    ? Herrerasauria incertae sedis
                         Protoavis texensis
                         Spinosuchus caseanus (may not be a dinosaur)
                    Family Herrerasauridae
                         Caseosaurus crosbyensis
               Infraorder Carnosauria
                    Superfamily Allosauroidea
                         Acrocanthosaurus atokensis
               Infraorder Coelurosauria
                    Superfamily Tyrannosauroidea
                         Family Tyrranosauridae
                              Tyrannosaurus rex
                         Saurornitholestes cf. langstoni
                    Maniraptora
                         cf. Deinonychus spp.
                         Richardoestesia cf. gilmorei
                         Richardoestesia isoceles
                    Aves
                         Flexomornis howei
       Suborder Sauropodamorpha
               Infraorder SAUROPODA
                    Family Titanosauridae
                         Astrophocaudia slaughteri 
                         Sauroposeidon proteles 
                         Alamosaurus sanjuanensis

     Order Ornithischia
           Suborder FABROSAURIA
                 Family Fabrosauridae
                      Technosaurus smalli
                      Tecovasaurus murryi (may not be a dinosaur)
           Suborder ORNITHOPODA
                 Family Hypsilophodontidae
                      new species near  Hypsilophodon foxi
                 Family Iguanodontidae
                      Tenontosaurus dossi
                      Tenontosaurus tilletti
                 Family Hadrosauridae
                     Protohadros byrdii
                     Gryposaurus sp. (Kritosaurus cf. navajovius)
                     cf. Edmontosaurus sp.
                     Angulomasticator daviesi
                     unnamed hadrosaur 

           Suborder Thyreophora
                 Infraorder ANKYLOSAURIA
                      Family Nodosauridae
                           Texasetes pleurohalio
                           Pawpawsaurus campbelli
                           Edmontonia rugosidens
                           unnamed ankylosaurs
           Suborder Marginocephalia
                 Infraorder PACHYCEPHALOSAURIA
                        Family Pachcephalosauridae
                             Texacephale langstoni.
                 Infraorder CERATOPSIA
                        Family Ceratopsidae
                             Chasmosaurus mariscalensis
                             Torosaurus cf. latus
                             undetermined genus and species

Texas Dinosaurs by Time

 _____________________________________________________________________
|late LATE CRETACEOUS          Big Bend Region  -  West Texas         |
|_____________________________________________________________________|
|                  |        Black Peaks Formation                     |
|  Maastrichtian   |        Javelina Formation   El Picacho Formation |
|__________________|__________________________________________________|
|                  |         Aguja Formation     San Carlos Formation |
|   Campanian      |         Pen Formation                            |
|                  |                                                  |
|   Santonian      |                                                  |
|   Coniacian      |                                                  |
|__________________|__________________________________________________|
 

Tyrannosaurus rex?
Richardoestesia
Saurornitholestes
Alamosaurus sanjuanensis
Gryposaurus sp.
cf. Edmontosaurus sp.
Angulomastacator daviesi
Texacephale langstoni
Chasmosaurus mariscalensis
Torosaurus cf. latus
Edmontonia longiceps
unnamed nodosaurids

Longrich, Sankey and Tanke (2010, table 1) list the following dinosaurian taxa from the Aguja Formation

Tyrannosauridae
    Tyrannosauridae indet.
Ornithomimidae
    Ornithomimid A
    Ornithomimid B
    Ornithomimid C
Oviraptorosauria
    Caenagnathidae indet.
Dromaeosauridae
    cf. Saurornitholestes sp.
Paraves incertae cedis
    Richardoestesia sp.
Hadrosauridae
    Kritosaurus sp.
    Lambeosaurinae indet.
Ceratopsidae
    Agujaceratops mariscalensis
Pachycephalosauridae
    Texacephale langstoni
Nodosauridae
    New genus and species

 ______________________________________________
|early LATE CRETACEOUS    North-Central Texas  |
|______________________________________________|
|      Turonian           |                    |
|______________________________________________|
|    Cenomanian           | Woodbine Formation |
|______________________________________________|

Protohadros byrdii
unnamed nodosaurid
unnamed hadrosaur
cf. Richardoestesia

 ____________________________________________________
|late EARLY CRETACEOUS       North-Central Texas     | 
|____________________________________________________|
|   |     |     |       |                            |
|_________|     |       |                            |
|   |     |     |  W    |                            |
|   |     |     |  A  G |                            |
|   |     |     |  C  r |    Paw Paw Formation       |
|   |     |     |  H  o |                            |
|   |     |     |  I  u |                            |
|   |     |     |  T  p |                            |
| E |  A  |  C  |  A    |                            |
| a |  L  |  O  |       |                            |
| r |  B  |  M  |       |                            | 
| l |  I  |  A  |_______|____________________________|     
| y |  A  |  N  |                                    |
|   |  N  |  C  |       Fredericksburg Group         |
| C |     |  H  |                                    |
| R |     |  E  |____________________________________|
| E |     |  E  | T    |                  |  A       |
| T |     |     | r  G | Paluxy Fm        |  n       |
| A |     |  S  | i  r |                  |  t  F    |
| C |_____|  E  | n  o | Glen Rose Fm     |  l  m    |
| E |  A  |  R  | i  u |                  |  e       |
| O |  P  |  I  | t  p | Twin Mountains Fm|  r       |
| U |  T  |  E  | y    |                  |  s       |
| S |  I  |  S  |      |                             |
|   |  A  |     |      |                             |
|   |  N  |     |      |                             |
|___|_____|_____|______|_____________________________|
 

Acrocanthosaurus atokensis
cf. Deinonychus
Sauroposeidon proteles
Astrophocaudia slaughteri
new species near Hypsilophodon foxi
Tenontosaurus dossi
Tenontosaurus tilletti
Texasetes pleurohalio
Pawpawsaurus campbelli
unnamed nodosaurids

 _______________________________________________________________
|LATE TRIASSIC              Texas Panhandle, West Texas         |
|_______________________________________________________________|
|                  |                                            |
|    Rhaetian      |                                            |
|__________________|                                            |
|                  |   Dockum Group                             |
|    Norian        |                     Bull Canyon Member     |
|__________________|                                            |
|                  |                     Tecovas Member         |
|    Carnian       |                     Colorado City Member   |
|                  |                     Camp Springs Member    |
|__________________|____________________________________________|
 

Caseosaurus crosbyensis (may not be a dinosaur, but is likely a dinosauriform)
Protoavis texensis (in part)
Spinosuchus caseanus (may not be a dinosaur)
Technosaurus smalli (may not be a dinosaur)
prosauropod indet. (may not be a dinosaur)
Tecovasaurus murryi (may not be a dinosaur)

Nesbitt and others (2007) reviewed the putative record of late Triassic record dinosaurs in North America.  The only taxon from Texas that they assigned to the Dinosauria is Protavis texensis (in part).

DINOSAURIA

Order SAURISCHIA

Suborder THEROPODA

Classification

• Order Saurischia
  • Suborder Theropoda

Infraorder HERRERASAURIA

Classification

• Order Saurischia
  • Suborder Theropoda
    • Infraorder Herrerasauria
      • Family Herrerasauridae
        • Caseosaurus crosbyensis
        • probably Protoavis texensis in part
        • possibly Spinosuchus caseanus

Caseosaurus Hunt, Lucas, Heckert & Lockley, 1998

Type and only species: Caseosaurus crosbyensis Hunt, Lucas, Heckert, Sullivan & Lockley, 1998

Locality

• Tecovas Member, Dockum Formation, Crosby County, Texas;  latest Carnian (Latest Triassic)

Comment

• Based on a right ilium originally attributed to Chindesaurus bryansmalli (Long and Murry, 1995).    Nesbitt and others (2007) refer it to the Dinosauriformes and state that it cannot be unambiguously assigned to the Herrerasauridae or Dinosauria.

Protoavis Chatterjee, 1991

Type and only species: Protoavis texensis Chatterjee, 1991

:Locality

• Dockum Formation, Texas;  Norian (Late Triassic)

Comment

• This small (mass = 350 g) dinosaur (in part) is based on skeletal material from at least 2 individuals (possibly from different taxa).  Protoavis was originally described as the oldest bird (Chatterjee, 1986, 1991), significantly older than the late Jurassic Archaeopteryx, usually regarded as the ancestral bird. Further analysis indicated that certain parts may belong to a primitive theropod, others to a pterosaur.   Hunt and others (1998) conclude that it is probably an aberrant theropod.  Nesbitt and others (2007) refer the dinosaurian parts to Coelophysoidea indet.
  

Spinosuchus von Huene, 1932

Type and only species: S. caseanus von Huene, 1932

Locality

• Dockum Group, north of Cedar Mountain, Crosby County,  latest Carnian (Late Triassic)

Comment

• specimens consist of vertebrae.  Once thought to be a "pseudosuchian", but may be a theropod.  Murry (1986) considers that it is probably a rauisuchian or poposaurian.  Nesbitt and others (2007) refer it to Archosauriformes incertae sedis.

Infraorder CARNOSAURIA

Classification

• Order Saurischia
  • Suborder Theropoda
    • Infraorder Carnosauria
      • Family Allosauridae

Acrocanthosaurus

Type and only species: A. atokensis  Stovall and Langston, 1950

Classification

• Order Saurischia
  • Suborder Theropoda
    • Superfamily Allosauridoidea

Distribution

• Trinity Group of Texas; also Antlers Formation, Oklahoma.  Aptian-Albian; late Early Cretaceous.

• The most complete skeleton known from Texas comes from the Twin Mountains Formation at Parker Ranch in Parker County (Harris, 1998).  Large isolated teeth attributable to this genus occur elsewhere in the Trinity.
• Check out Karen Carr's image of Acrocanthosaurus attacking Pleurocoelus for the Fort Worth Museum of Science and History.

� Karen Carr, used by permission of Louis L. Jacobs; click to enlarge

• The carnivorous Acrocanthosaurus was a large allosauroid, 8 to 12 meters long and weighing 2 to 3 tons.  Its name comes from the long vertebral spines along its back.  These have been interpreted as forming a sail.  However, Bailey (1997) interprets that these neural spines instead formed a broad (buffalo-like) hump.  See below for information on  footprints.
• Acrocanthosaurus is most closely related to the early Cretaceous, African genus Carcharodontosaurus.

Infraorder COELUROSAURIA

Classification

• Order Saurischia
  • Suborder Theropoda
    • Infraorder Coelurosauria
      • Tyrannosauroidea
      • Maniraptora

Tyrannosaurus Osborn, 1905
Classification

• Order Saurischia
  • Suborder Theropoda
    • Infraorder Coelurosauria
      • Superfamily Tyrannosauroidea

Tyrannosaurus rex Osborn, 1905 (type)

Texas Locality

• Brewster County, lower part of the Tornillo Group; Maastrichtian (latest Cretaceous).

Texas material.

• This genus is recognized from Big Bend National Park from a maxilla with teeth described by Lawson (1976).  It was suggested that the relatively small size of this specimen may be because it is a young adult or because it is from a smaller theropod such as Albertosaurus. 
• Carr and Williamson (2000, 2004) identify the Tornillo Formation tyrannosaurid as T. rex.
•  Tyrannosaurid  teeth are also known from the Campanian Aguja formation (Sankey, 2001).
• Karen Carr's Big Bend T. rex.

Saurornitholestes Sues, 1970
Classification

• Order Saurischia
  • Suborder Theropoda
    • Infraorder Coelurosauria
      • Superfamily Tyrannosauroidea

Sauronitholestes cf. langstoni Sues, 1970

Texas Locality

• Aguja Formation, Campanian (late Cretaceous).

Texas material.

• teeth or teeth fragments (Sankey, 2001)

cf. Deinonychus

Classification

• Order Saurischia
  • Suborder Theropoda
    • Maniraptora

Texas Localities

• This genus has been reported from isolated teeth from the Trinity Group of Texas (Winkler and others, 1988; Jacobs, 1995), but the material has not been described in detail .  Brinkman and others (1998) note that the dromaeosaurid teeth from the lower Trinity Group are considerably smaller than those from the Cloverly Formation (type locality) of Montana and Wyoming and those from the upper Trinity are the same size or larger then the Cloverly Deinonychus.
• Associations of Tenontosaurus and its predator Deinonychus have been discovered in Montana and Oklahoma, and possibly in Texas (a few dromaeosaurid teeth occur with the Doss Ranch specimens).

Richardoestesia Currie, Rigby, and Sloan, 1990

Classification

• Order Saurischia
  • Suborder Theropoda
    • Infraorder Maniraptora
      • family unknown

Richardoestesia cf. gilmorei Currie, Rigby, and Sloan, 1990
Richardoestesia isosceles Sankey, 2001

Texas Localities

• This genus is tentatively recognized from the Cenomanian Woodbine Formation (Lee, 1997).   Richardoestesia cf. gilmorei and R. isosceles occur in the Judithian (Campanian) Aguja Formation (Sankey, 2001).

Theropoda indet.

• Isolated teeth from the Aguja Formation referred to the maniraptoran cf. Dromaeosaurus (Rowe and others, 1992) have been reassigned to theropod genus and species undetermined (Sankey, 2001).

Class Aves

Subclass Enantiornithes

Flexomornis howei Tykoski & Fiorillo, 2010

Suborder SAUROPODA

Classification

• Order Saurischia
  • Suborder Sauropodamorpha
    • Infraorder Sauropoda

Sauroposeidon Wedel, Cifelli, and Sanders, 2000

Classification

• Order Sauropodamorpha
  • Infraorder Sauropoda
    • Titanosauridae

Type and only species: Sauroposeidon proteles Wedel, Cifelli, and Sanders, 2000
Senior synonym of  Paluxysaurus jonesi Rose 2007

Locations

• Glen Rose Formation and Paluxy Formation; early Albian (about 110 Ma), late early Cretaceous.

Comments

• A mounted skeleton is on exhibit at the Fort Worth Museum of Science and History.
• This dinosaur made the huge "wash basin" footprints in the early Cretaceous, Glen Rose Formation.

            Image from Roland T. Bird's, 'A Dinosaur Walks into the Museum,' published in Natural History, February 1941. reprinted with permission.

• Previously it was referred to Pleurocoelus, a brontosaur seventy feet long and weighing twenty tons.  However, assignment to this genus was considered uncertain (Langston, 1974).   Pleurocoelus is sometimes considered a junior synonym of Astrodon (e.g., Brinkman, Cifelli, and Czaplewski, 1998), the state fossil of Maryland.  
• Wedel, Cifelli, and Sanders (2000) described Sauroposeidon proteles, as a new brachiosaurid sauropod from the early Cretaceous Antlers Formation of Oklahoma and suggested that other material referred to Pleurocoelus needed to be reexamined. 
•   Rose (2007) established a new genus and species for the early Cretaceous sauropod from Texas. The holotype of Paluxysaurus is FWMSH 93B-10-18, an associated left maxilla and nasal, and teeth from Jones Ranch.
• Rose (2007) distinguished the new Texas genus from previously named taxa, and concludes that both Pleurocoelus and Astrodon should be considered incertae sedis.
• d'Emic and Foreman (2012) and d'Emic (in press) synonymized  Paluxysaurus jonesi with Sauroposeidon proteles and determined that it was a titanosaur.
• Karen Carr's image for Lone Star Dinosaurs shows that even a Paluxysaurus could become a meal for Acrocanthosaurus.

 Karen Carr, used by permission of Louis L. Jacobs

• The state dinosaur of Texas.  

Tidwell and Carpenter (2003) described the braincase and partial skeleton of a juvenile titanosauriform sauropod from the Glen Rose Formation in Blanco County that is not diagnostic at the genus level (D"Emic, in press). 

Astrophocaudia D"Emic, in press.

Classification

• Order Saurischia
  • Suborder Sauropoda
    • Family Titanosauridae
      • Astrophocaudia slaughteri d"Emic, in press

Alamosaurus Gilmore, 1922

Classification

• Order Saurischia
  • Suborder Sauropoda
    • Family Titanosauridae
      • Alamosaurus sanjaunensis.

Alamosaurus, from Wikipedia - Bogdanov, 2006

Distribution

• Texas, Big Bend: Black Peaks, Javelina, and El Picacho Formations; also New Mexico, Utah.
• The Alamosaurus fauna is Lancian to late Edmontonian  (late Maastrichtian, latest Cretaceous) in age (Lehman and others, 2006) .

Comments

• Alamosaurus was 21 m long and weighed at least 30 tons.  It is the only North American sauropod from the Late Cretaceous (Maastrichtian).  Although it is known from Texas, it is not named after the Alamo in San Antonio, but after the Ojo Alamo Formation (the type locality is now recognized as the Kirtland Shale), at the Ojo Alamo (Spanish for cottonwood spring) trading post in the San Juan Basin, New Mexico (Gilmore, 1922).
• Alamosaurus may represent an invasion from South America by titanosaurids, following the mid-Cretaceous extinction of the brachiosaurids in North America.   Lehman and Coulson (2002) conclude that Alamosaurus is most closely related to titanosaurs from Brazil and Argentina.
• Myers and Fiorillo (2009) used fossils from the Javelina Formation to demonstrate Alamosaurus formed age-segregated herds.
• Fowler and Sullivan (2011) make the case that Alamosaurus sanjaunensis is one of the largest dinosaurs in the world, because it is based on the remains of juveniles, as shown by Woodward and Lehman (2009).

DINOSAURIA

Order ORNITHISCHIA

Suborder FABROSAURIA

Classification

• Order Ornithischia
  • Suborder Fabrosauria
    • Family Fabrosauridae
      • Technosaurus smalli
      • Tecovasaurus murryi

Technosaurus Chatterjee, 1984.

Type and only species:  T. smalli Chatterjee, 1984 (type)

Location and age: Dockum Group, Texas Panhandle, Norian (late Triassic).

Comment:

• This 1 to 2 m long putative primitive dinosaur is known only from a right lower jaw.  A premaxilla and a posterior lower jaw that had been assigned to this taxon were reassigned to an indeterminate prosauropod (Sereno, 1992; Hunt and others, 1998).  Irmis and others (2007) consider the premaxilla as belonging to a form similar to the ornithischian-like dinosauromorph Silesaurus and the posterior jaw to Shuvosaurus.
  

Tecovasaurus Hunt & Lucas, 1994

Type and only species: T. murryi Hunt & Lucas, 1994 (type)

Localities

• Tecovas Formation, Crosby County, Texas and New Mexico and Arizona; Carnian (late Triassic)

Comment

• This taxon is based on isolated teeth.  Irmis (2005) notes that isolated teeth cannot be used to assign specimens to the Ornithischia and instead refers Tecovasaurus to Archosauriformes incetae sedis.

Suborder ORNITHOPODA

Classification

• Order Ornithischia
  • Suborder Ornithopoda

Family HYPSILOPHODONTIDAE

Hypsilophodont - new species, similar to Hypsilophodon foxi (see Winkler and others, 1988; Winkler and Murry, 1989)

Classification

• Order Ornithischia
  • Suborder Ornithopoda
    • Family Hypsilophodontidae

Location

• Twin Mountains Formation, Proctor Lake, Commanche County, Texas, late Aptian (late Early Cretaceous), about 115 Ma.

Comments

� Karen Carr, used by permission of Louis L. Jacobs.  Karen Carr's image for Lone Star Dinosaurs shows a group of  these small hypsilophodonts cavorting in front of a Tenontosaurus.   This temporary display at the Dallas Museum of Natural History shows a skeleton of this as-yet, unnamed primitive ornithopod.

• The Proctor Lake locality, discovered by Tarleton State University student Rusty Branch, has a few adults and clusters of juvenile hypsilophodontids, possibly indicating a nesting site, although no eggs have been found. (Winkler and Murry, 1989).

IGUANODONTIA

Tenontosaurus

Classification

• Order Ornithischia
  • Suborder Ornithopoda
    • Family Iguanodontidae

Comments

• Tenontosaurus is the large dinosaur in the illustration by Karen Carr  for Lone Star Dinosaurs 

� Karen Carr, used by permission of Louis L. Jacobs; click to enlarge

• Tenontosaurus is the most common large herbivore known from the late early Cretaceous of North America. 
• Tenontosaurus is intermediate in morphology between hypsilophodontids and iguanodonts (Winkler and others, 1997).
• Associations of Tenontosaurus and its predator Deinonychus have been discovered in Montana and Oklahoma, and possibly in Texas (a few dromaeosaurid teeth occur with the Doss Ranch specimens).

Tenontosaurus dossi Winkler and others, 1997.

Location

• Twin Mountains Formation, Parker County, Texas, latest Aptian (approximately 113 Ma)

Comments

• In 1988, seven-year-old Thad Williams and his father Ted discovered this new species of primitive iguanodont.
• Tenontosaurus dossi is slightly more primitive than Tenontosaurus tilletti.

Tenontosaurus tilletti?

Comment

• Tenontosaurus tilletti is known from the Cloverly Formation, Montana. This species probably occurs in higher levels of the Trinity Group (Glen Rose and Paluxy Formations) of Texas (Winkler and others, 1997).

Family HADROSAURIDAE

Hadrosaur tree from Wikipedia. Click on image to enlarge.

Classification

• Order Ornithischia
• Suborder Ornithopoda
  • Family Hadrosauridae
    • Subfamily Hadrosaurinae
      • Protohadros byrdii
      • unnamed hadrosaur
      • Kritosaurus navajovius
    • Subfamily Lambeosaurinae
      • Angulomastacator daviesii

Subfamily Hadrosaurinae

Protohadros  Head, 1998

Type and only species: Protohadros byrdii Head 1998

Location

• Flower Mound (north of Dallas-Fort Worth, Texas), Woodbine Formation, Cenomanian (early late Cretaceous), 95 Ma.

Comment

• Protohadros is intermediate in morphology between the iguanodonts and the other hadrosaurids (Head, 1998).  It is the one of the oldest and most primitive named hadrosaurids, a group that was to become increasingly important in the late Cretaceous.

Main and Fiorello (2003) report finding hadrosaur postcrania along the shores of Lake Grapevine from the Woodbine Formation.

Kritosaurus Brown, 1910 or Gryposaurus Lambe, 1914

Texas species:

• Kritosaurus cf. navajovius (or n. sp. or ?Gryposaurus n. sp). from the Pen Formation, San Carlos Formation, Aguja Formation, and El Picacho Formation. 

Comment

• Because Kritosaurus navajovius (Brown, 1910) is based on very poor material,   Gryposaurus is the preferred name for this hadrosaurine according to Weishampel and Horner (1990). However, Rowe and others (1992) refer some of the Aguja hadrosaurines to Kritosaurus.  However, reversing their opinion of the previous year. Hunt and Lucas (1993) conclude that Kritosaurus navajovius is a nomen dubium.
  Sankey (2001) stated that Kritosaurus cf. navajovius and an unidentified lambeosaurine (=Angulomastacator) and an indeterminate hadrosaurid occur in the Aguja Formation.  In an abstract, Wagner and Lehmann (2001) refer the Aguja hadrosaur to Kritosaurus n. sp.  Gates and Sampson (2007) suggest the Aguja material may be attributable to Gryposaurus n. sp.

Subfamily Lambeosaurinae

Angulomastacator Wagner and Lehman 2009

Type and only species: Angulomastacator daviesi Wagner and Lehman, 2009

Location: upper shale member, Aguja Formation

• It is known from a single specimen, a partial left maxilla, with an abrupt ventral deflection.

Suborder Marginocephalia

Infraorder PACHYCEPHALOSAURIA
Family Pachycephalosauridae


Skeletal reconstruction of Stegoceras. From Wikipedia

Texacephale langstoni Longrich, Sankey and Tanke 2010

Type and only species: Texacephale langstoni Longrich, Sankey and Tanke 2010

Location: upper shale member, Aguja Formation

•  This genus is represented by fused frontoparietals and an incomplete frontoparietal dome.  See below for doubts about its validity by Lehman (2010) and Jasinski and Sullivan (2011).

?Stegoceras sp. and Pachcephalosauridae incertae sedis

Lehman (2010) described several fragmentary frontoparietal domes from the San Carlos and Aguja Formations as belonging to more than one taxon: one similar to Stegoceras or Gravitholus, the other an indeterminate pachycepahalosaurid.  The paper was in press at the time Texacephale (Longrich and others, 2010) was described.  In a note added in proof, Lehman (2010) states that none of his specimens can be referred with confidence to Texacephale, and casts doubt on the significance of the features used to diagnose Texacephale. Jasinski and Sullivan (2011) agree that Texacephale langstoni is not based on diagnostic material and is "therefore a nomen dubium."

Teeth from the Aguja Formation assigned to cf. Troodon (Rowe et al., 1992) have been re-identified as belonging to an indeterminate pachycephalosaurid (Sankey, 2001).

Infraorder CERATOPSIA

Classification

• Order Ornithischia
  • Suborder Marginocephalia
    • Infraorder Ceratopsia
      • Family Ceratopsidae
        • Subfamily Chasmosaurinae
          • Agujaceratops mariscalensis
          • Torosaurus utahensis
          • undetermined genus and species

Comment

• In Texas, ceratopsian dinosaurs occur in Campanian and Maastrichtian (late Cretaceous) sediments in the Big Bend area.

Chasmosaurus or Agujaceratops

Chasmosaurus mariscalensis Lehman, 1989
Agujaceratops mariscalensis Lucas, Sullivan, and Hunt 2006

Distribution

• Aguja Formation, Texas; Campanian (Judithian) (late Cretaceous)

Comments

• A nearly complete skull of this ceratopsian is described by Forster and others (1993).  Lucas, Sullivan, and Hunt (2006) established a new genus Agujaceratops for this species.  Hunt and Lehman (2008) continued to refer this species to Chasmosaurus.

Agujaceratops mariscalensis, illustration by ArthurWeasley

Torosaurus Marsh, 1891, perhaps now Triceratops Marsh, 1889

Distribution

• late Maastrichtian (Lancian; Late Cretaceous).  Torosaurus, originally described from Wyoming, is also known from the Javelina Formation, Tornillo member, Texas, and elsewhere. 
• Lawson (1976) referred two Texas specimens to Torosaurus utahensis.  Farke (2002) stated that one of these specimens, a partial right parietal, can be referred to Torosaurus sp.; the other, a partial orbital horn, to Chasmosaurinae indet.  Sulivan, Boere, and Lucas (2005) considered the Big Bend specimens (Lawson, 1976; Lehman, 1996) as indeterminate chasmosaurines.  Hunt and Lehman (2008) described 37 additional specimens from the Javelina Formation as belonging to T. cf. utahenesis, although recognizing that this is a tentative assignment.

Comments

• This ceratopsian had one of the largest skulls of any terrestrial vertebrate, approximately 8 feet long (exceeded only by a specimen of Pentaceratops (Lehman, 1998).
• Size: 6-8 m (no complete skeletons are known), 7-8 tons.
• Scannella and  Horner (2010) determined that Torosaurus is a junior synonym of Triceratops, and that specimens identified as Torosaurus are just very mature Triceratops individuals.  They state "that �Torosaurus� utahensis is either a species of Triceratops, or a different genus; either Arrhinoceratops ... or its own distinct genus."  Their preferred hypothesis is that it is  a species of Triceratops.
• Farke (2011) disputes Scannella and Horner's interpretation and states "it is far more likely that Triceratops, Torosaurus, and probably Nedoceratops, are distinct taxa"

Genus and species undetermined Lehman 1996

Distribution

• Picacho Formation, Texas;  Maastrichtian (latest Cretaceous)

Suborder Thyreophora

Infraorder ANKYLOSAURIA

Classification

• Order Ornithischia
  • Suborder Thyreophora
    • Infraorder Ankylosauria
      • Family Nodosauridae

Comment

• Texas nodosaurids (such as Pawpawsaurus) are found in early and late Cretaceous marine sediments in Texas and elsewhere.  They frequented the coast of the ancient sea.

Pawpawsaurus Lee, 1996

Type and only species: Pawpawsaurus campbelli Lee, 1996

• Location
  • Paw Paw Formation, Tarrant County (north of Fort Worth), Texas, late Albian (latest Early Cretaceous), about 100 Ma.
• Material
  • A skull, with bony eyelids (Lee, 1996).  Cameron Campbell has a  website devoted just to his Texas Pawpawsaurus .

Texasetes Coombs, 1995

Type and only species: Texasetes pleurohalio Coombs, 1995.

• Location
  • Paw Paw Formation, Tarrant County (north of Fort Worth), Texas, late Albian (latest Early Cretaceous), about 100 Ma.
• Material
  • two teeth and much of a skeleton (Coombs, 1995) of a nodosaur about 3 m long.
• Comment
  • According to Lee (1996), this material is not diagnostic beyond Nodosaurid indet.

Nodosauridae indet.

• Unnamed nodosaurid material occurs in the Woodbine Formation, and includes a skeleton of a baby (Jacobs, 1995; Lee, 1997).

Edmontonia Sternberg, 1928

Edmontonia longiceps Sternberg 1928

Type specimen: NMC 8531, a partial skeleton, Horsehoe Canyon Formation, Alberta, Canada, Maastrichtian, latest Cretaceous).

Texas location: Aguja Formation, Campanian (Judithian), late Cretaceous

Coombs (1978) diagrammatically illustrated  a partial skull (AMNH 3076) from the Aguja Formation that he referred to Panoplosaurus sp. Carpenter (1990) reported Edmontonia sp. and Panoplosaurus sp. from the Aguja Formation. Coombs and Marya�ska. (1990) referred the Aguja specimens to E. rugosidens.  Lee (1996) referred AMNH 3076 to Edmontonia.  Vickaryous (2006) assigned the Texas material (including AMNH 3076) of Edmontonia to E. longiceps, a species related to, but geologically younger than E. rugosidens.

TRACE FOSSILS

THE GLEN ROSE TRACKWAY

• Hawthorne (1990) provides a good introduction to Glen Rose trackways.
• The large dinosaur footprints in the Glen Rose trackways have been assigned to the ichnotaxon Brontopodus birdi (Farlow and others, 1989),  named in honor of Roland T. Bird, who excavated a long trackway for the American Museum of Natural History.  They were likely made by Paluxysaurus (formerly Pleurocoelus). Wedel and Cifelli (2006) state that the tracks are so large they must have been made by the giant sauropod Sauroposeidon. Theropod trackways have been referred to Grallator sp. and were probably made by Acrocanthosaurus. (Rogers, 2002).

Dinosaur footprint in Glen Rose Formation near Tarpley, Texas. Click on image to enlarge

• Dinosaur Valley State Park in the early Cretaceous, Glen Rose Formation.
• Learn more about the Paluxy River tracksite and more from Glen Kuban.  There are no human footprints here (Milne and Schafersman, 1983).
• There are numerous other tracksites in the Glen Rose Formation, such as those at Davenport Ranch (Lockley and Hunt, 1995), Kinney County (Rogers, 2002), Boerne (Hawthorne et al., 2002), and the new Glen Rose tracksite shown below.

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New dinosaur track site near Glen Rose, Texas discovered by Lance Hall and Roz Morgan of the Dallas Paleontological Society.  DPS member Roger Fry is shown measuring dinosaur footprints.  Click on small images to enlarge.

Other Texas Mesozoic Life

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Other Texas Archosauriforms

Classification follows Brusatte and others (2010) and/or Nesbitt (2011).  Brusatte and others recognize stem archosauriforms and two major groups of archosaurs, the Avemetarsalia (including pterosaurs and dinosauromorphs) and Crurotarsi (including phytosaurs, aetosaurs, crocodylomorphs, and ornithosuchids, and rauisuchians).    Nesbitt includes the phytosaurs in the basal archosauriforms.

Basal Archosauriformes (from Nesbitt, 2011)

Vancleavea campi Long and Murry, 1995.   Tecovas Formation, Dockum Group, Texas.

Avemetatarsalia

• This group includes the dinosaurs (including birds) and pterosaurs. 
• Dromomeron gregorii Nesbitt et al., 2009 from the Otis Chalk Quarry 3, Howard County, Texas, is a stem dinosauromorph.

Order Pterosauria

Pterosaurs soared over the oceans of Texas more than 100 million years ago.

Eudimorphodon

• Dockum Group, Carnian (220 million years ago)
• This record based on jaw fragments containing multicusped teeth (Murry, 1986) may be the earliest for pterosaurs (Andres, 2006)

Quetzalcoatlus northropi

Life restoration of a group of giant azhdarchids, Quetzalcoatlus northropi, foraging on a Cretaceous fern prairie.  Figure 9 in Mark P. Witton and Darren Naish.  2008.  A reappraisal of azhdarchid pterosaur functional morphology and paleoecology. 
 PLoS ONE 3(5): e2271. doi:10.1371/journal.pone.0002271

• Javelina Formation (Keller and Langston, 1996, JVP 16:222-231)
• The great Texas pterosaur
• Quetzalcoatlus was the largest animal ever to fly under its own power, having a wing span of 11-12 m long (almost forty feet) and a weight of about 90 kg..

Tupuxara sp.

• A partial skull from the Javelina Formation previously referred to Quetzalcoatlus sp. has been reassigned to this related genus (Martill and Naish, 2006).

Uktenadactylus wadleighi

• This species was described by Lee (1994) from for a snout found in the Paw Paw Formation as Coloborhynchus wadleighi.  It was reassigned to a new genus Uktenadactylus by Rodrigues and Kellner (2008)

Aetodactylus halli Myers, 2010a

• Type specimen: SMU 76383, an elongate mandible, from the Upper Cretaceous Tarrant Formation of the Eagle Ford Group, a Cenomanian marine sandstone.  Photograph courtesy of Lance Hall, who discovered the specimen in 2006 and donated it to the Shuler Museum of Paleontology at Southern Methodist University.

Myers 2010b reported cf. Pteranodon from the Coniacian Atco Formation in the Austin Group: "Flying Texas reptile, World's Oldest Pteranodon?"

Azhdarichiidae indet.

• Glen Rose Formation (Murry et al., 1991)

Pterosauria indet.

• Antlers Fm.

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Crurotarsi

• The second clade of archosaurs that includes the phytosaurs and Suchia.  Classification follows Brusatte and others (2010) and/or Nesbitt (2011).

Order Phytosauria

Triassic phytosaurs resemble modern alligators which inhabit southeast Texas today, but the resemblance is only superficial. For example, the nostrils of an alligator are on the tip of the snout, while the nostrils of a phytosaur are between its eyes. The similarity of appearance results from convergent evolution - adaptation to a similar kind of lifestyle by different kinds of animals.

Rutiodon from Wikipedia. Illustration by Nobu Tamura.

Family Phytosauridae

Stocker (2010) identifies the following phytosaurs from Texas.

• Angistorhinus sp.
• Paleorhinus sawini, P. bransoni, and P. sp.
• A possible third taxon, TMM 31173-120, previously referred to Leptosuchus (=Rutiodon) crosbiensis by Long and Murry (1995)

Nesbitt (2011) includes Pseudopalatus pristinus Mehl, 1928  from the Bull Canyon Formation of the Dockum Group.

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SUCHIA

Order AETOSAURIA

Family Stagonolepidae

• Coahomasuchus kahleorum  Heckert and Lucas, 1999.
  • Howard County, Texas, Colorado City Formation, Dockum Group, late Carnian, late Triassic
• Desmatosuchus smalli 
  • Bull Canyon Formation, Dockum Group (Small, 1989; 2002; Parker, 2005)
• Sierritasuchus macalpini  Parker et al., 2008.
  • Tecovas Formation (Dockum Group) in Potter County, Texas
  • Long and Murry (1995) assigned this specimen to Desmatosuchus haplocerus
• Tecovasuchus chatterjeei Martz and Small, 2006.
  • Tecovas Formation
• Paratypothorax sp.  Long and Murry, 1995
• Typothorax coccinarum (Small, 1989; 2002; Parker, 2005)
  • Post (Miller) Quarry, Garza County, Bull Canyon Formation, Dockum Group, Norian, late Triassic

Nesbitt (2011) includes

• the aetosaur Longosuchus meadei (Sawin, 1947), sensu Hunt and Lucas, 1990 Otis Chalk area, and
• and the sister taxon of the aetosaurs Revueltosaurus callenderi Hunt, 1989 Bull Canyon Formation of the Dockum Group

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Order CROCODYLIA

(crocodile classification: Brochu, 1997, Jour. Vert. Paleont., 17:679-697; 2003, Ann. Rev. Earth Planet. Sci., 31:357-397.)

Paluxysuchus newmani, gen. et sp. nov. Adams, 2013

• Twin Mountains Formation, late Aptian
• A neosuchian crocodyliform

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the ‘Glen Rose form’ Langston, 1973, 1974

• Adams (2013) notes that a second small taxon from the Antlers Formation in northern Texas, represented by a skull,  has affinities closer to Eusuchia than to atoposaurids

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Pachycheilosuchus trinquei Rogers, 2003

• Glen Rose Formation
• This mesoeucrocodylian is closely related to atoposaurids (Rogers, 2003)
• from near-shore, marine-to-brackish deposits of the Albian Glen Rose Formation in Erath County. Estimated body length is 60-80 cm.  Rogers (2000) has also described an egg from this species. He (2003)  notes the presence of  other Glen Rose crocodylians, particularly the "Glen Rose Form" (Langston, 1974).

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Woodbineosuchus byersmauricei Lee, 1997

• lowermost Woodbine Formation.
• A narrow snouted, fish-eating goniopholid.

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Terminonaris cf. T. robusta

• Adams and others (2011)
• Arlington Member, uppermost Woodbine Formation, Upper Cretaceous (lower middle Cenomanian).
• a long-snouted Pholidosauridae

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Goniopholis cf. G. kirtlandicus

• Aguja formation (Rowe and others, 1992)

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Brachychampsa

• Aguja Formation (Sankey, 2008)

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Deinosuchus rugosus Holland, 1909  (=Phobosuchus riograndensis Colbert and Bird, 1954)

Mostly plaster reconstructed Deinosuchus skull that was exhibited at the American Museum of Natural History.  Image from Wikipedia.  The discovery, naming, and history of this specimen are briefly discussed in Wikipedia.

• upper Aguja Formation
• Known (until recently) from two skulls, each about 2 m long.   One of the largest extinct crocodilian yet found, Deinosuchus may have preyed on smaller dinosaurs.  Deinosuchus had been estimated to be over 45 feet in length extrapolated from skull size (largest recent crocodile is around 33 ft).  Recent discoveries indicate that it was 9 to 12 meters long and had a body mass of 2,500 to 5,000 kg, three to five times more than the largest crocodiles alive today (Erickson and Brochu, 1999; Schwimmer, 2002).
• Which was bigger (by D. L. Parsell, National Geographic News) Deinosuchus or Sarcosuchus (supercroc)

(crocodile classification: Brochu, 1997, Jour. Vert. Paleont., 17:679-697; 2003, Ann. Rev. Earth Planet. Sci., 31:357-397.)

 

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RAUISUCHIA

• A diverse assemblage of middle to late Triassic crurotarsans.

Poposaurus

• Poposaurus gracilis Mehl, 1915
• Poposaurus langstoni (Long and Murry, 1995)

Texas Locations

• Post Quarry, Garza County, Bull Canyon Formation, Dockum Group, Norian, late Triassic (Parker, 2005), Tecovas and Copper Canyon Formations, Dockum Group, Norian, late Triassic.
• Weinbaum and Hungerbuhler (2007) referred Postosuchus kirkpatricki  (Chatterjee, 1985) to Poposaurus gracilis.
• Weinbaum and Hungerbuhler (2007) referred Lythrosuchus langstoni  (Long and Murry, 1995) to Poposaurus langstoni.

Postosuchus Chatterjee, 1985

• Postosuchus kirkpatricki  Chatterjee, 1985

Location

• Post Quarry, Garza County, Bull Canyon Formation, Dockum Group, Norian, late Triassic

Comments

• Weinbaum and Hungerbuhler (2007) noted that some of the material referred to Postosuchus kirkpatricki by Chatterjee belongs to Poposaurus gracilis.
• Weinbaum (2011) described the skull of Postosuchus kirkpatricki.

 

Shuvosaurus

Type and only species

• S. inexpectatus Chatterjee, 1993

Location

• Post Quarry, Garza County, Bull Canyon Formation, Dockum Group, Norian, late Triassic

Comment

• Chatterjee (1993) described this taxon, based on skull fragments, an edentulous dentary, and a dorsal vertebra, as an ornithomimosaurian theropod.  Long and Murry (1995) suggested that it was a ?rauisuchian that they named Chatterjeea elegans.   Nesbitt and Norell (2006) synonymized Chatterjeea elegans with S. inexpectatus.
• Hunt and others (1998) noted that Shuvosaurus lacks any dinosaurian synapomorphies and tentatively supported Long and Murry's interpretation.  Rauhut (1997) suggested it is an early coelophysid.  Nesbitt and Norell (2006) concluded that Shuvosaurus is related to the early suchian crocodylian Effigia, a toothless form convergent with the ornithomimids.  Weinbaum and Hungerbuler (2007) considered it a "rauisuchid" closely related to Poposaurus.

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Mesozoic marine Reptiles that are not archosaurs

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PLESIOSAURS

These aquatic sauropterygian lepidosauromorphs of the Mesozoic epicontinental seaways have four paddle-shaped (Wing-fins of Adams, 1998) limbs.  Both long necked (plesiosauroids or elasmosaurs) and short necked forms (pliosauroids) are present in Texas.   In a published abstract of his unpublished 1981 thesis, Storrs (1983) states that five genera of plesiosaurs have been described from Texas.  The abstract briefly discusses the four valid genera: Trinacromerum, Thalassomedon, ?Alzadasaurus, and Polyptychodon.

Polytychodon hudsoni is a short necked plesiosaur.  It was found in the Eagle Ford Formation during the excavation for the old Braniff terminal at DFW airport (Oceans Dallas p.12 ). 

Plesiosaur Unearthed During Preliminary Excavation for the Dallas-Fort Worth International Airport. The Portal to Texas History. http://texashistory.unt.edu/ark:/67531/metapth28009/. Accessed October 11, 2009.

Libonectes morgani (Welles 1949) is a very long-necked elasmosaurid plesiosaur from the Britton Formation, Eagle Ford Group, near Cedar Hill, Dallas County, Texas.

Ceraunosaurus brownorum Thurmond (1968) is a short-necked pliosaur from the Lake Waco Formation (Cenomanian).  Storrs (1981, 1983) states that this genus "is an obvious specific variant of Tricanomerum."

Brachauchenius lucasi, a very large pliosaur, was first collected in Kansas (Williston, 1903). A second specimen (UNSM 2361) was collected from the Eagle Ford formation near Austin, Texas (Williston, 1907).  A skull from Kansas is about  1.5 m. long.

Trinacromerum bonneri Adams is known from the latest Cretaceous Taylor Marl, as well as the type locality in South Dakota.  Trinacromerum is a pliosaur, all high speed swimmers, of which this is the fastest.

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MOSASAURS

These are giant marine, varanoid lizards, that may be ancestral to snakes.  Their diet included ammonites. Recently, Tomoki Kase (Geology, 1998) indicated that the putative puncture marks are weakened areas of the shell where limpets attached to the dead ammonites' shells.  This has been disputed and evidence for mosasaur predation on ammonites has been strongly supported  (Tsujita and Westermann, 2001,Palaeogeography,Palaeoclimatology, Palaeoecology; Kauffman, 2004, PALAIOS). Additional information can be found at Oceans of Kansas and from Ben Creisler at Dinosauria on Line.

Tylosaurus proriger.

• This 10 meter-long, late Cretaceous mosasaur (the Heath mosasaur, photograph courtesy of Lance Hall)  is on display at the Dallas Museum of Nature and Science.  Tylosaurus reached a maximum length of 15 meters.

Globidens

• Polcyn and Bell (2005a) recognize this rare durophagous (teeth capable of crushing hard-shelled mollusks) mosasaur from North-Central Texas.  They note that Platecarpus intermedius belongs in this genus.

Mosasaurus maximus: the Onion Creek mosasaur, another large marine lizard, about 9 meters long. The largest specimen (from New Jersey) is 13 meters long.

Halisaurus

• Caldwell and Bell (1995) refer a series of dorsal vertebrae from the Upper Cretaceous Pen Formation to this genus

Dallasaurus turneri

• Bell and Polcyn (2005) describe a primitive mososaur with four limbs that was discovered near Dallas.

Russellosaurus coheni Bell and Polcyn (2005)

• This new genus is described by Polcyn and Bell (2005b) from Cedar Hill, Dallas County, Texas.  This 92 Ma species is represented by the oldest well-preserved mosasaur skull from North America.

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ICHTHYOSAURS

Ichthyosaurs are the most fully-aquatic reptiles.  They are now classified as primitive diapsids

Main and Fiorello (2002) note in an abstract that the common Cretaceous genus Platypterygius is known from the Grayson Marl (lower Cretaceous) in Tarrant County.  Platypterygius has a better fossil record in Australia

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REFERENCES

Adams D.A. 1997. Trinacromerum bonneri, New species, last and fastest pliosaur of the Western Interior Seaway. Texas Journal of Science, 49(3): 179-198.

Adams 2013 A New Neosuchian Crocodyliform from the Lower Cretaceous (Late Aptian) Twin Mountains Formation of North-Central Texas. Journal of Vertebrate Paleontology, 33:85-101.

Adams, T. L., M. J. Polcyn, O. Mateus, D. A. Winkler, and L. L. Jacobs  2011.  First occurrence of the long-snouted crocodyliform Terminonaris (Pholidosauridae) from the Woodbine Formation (Cenomanian) of Texas. Journal of Vertebrate Paleontology, 31:712-716.

Andres, B.  2006.  The earliest pterosaurs.  Journal of Vertebrate Paleontology 26(3 Supplement):37A.

Baghai-Riding, N.L. and DiBenedetto, J.N.   2001.  An unusual dinosaur coprolite from the Campanian Aguja Formation, Texas.  Transactions of the Gulf Coast Association of Geological Societies, Vol.51, p.9-20.

Bailey, J. B. 1997.  Neural spine elongation in dinosaurs: sailbacks or buffalo-backs.  Journal of Paleontology, 71:1124-1146.

Bell, G. L. and M. J. Polecyn.  2005.  Dallasaurus turneri, a new primitive mosasauroid from the Middle Turonian of Texas and comments on the phylogeny of Mosasauridae(Squamata).  Netherlands Journal of Geosciences, Geologie en Mijnbouw, 8:177-194.

Brinkman, D. L., Cifelli, R., and Czaplewski, N. J.  1998.   First occurrence of Deinonychus antirrhopus (Dinosauria: Theropoda) from the Antlers Formation (Lower Cretaceous: Aptian-Albian) of Oklahoma.  Oklahoma Geological Survey, Bulletin 146:1-27.

Brusatte, S. L.,Benton, M. J., Desojo, J. B., and Langer, M. C. 2010. The higher-level phylogeny of Archosauria (Tetrapoda: Diapsida). Journal of Systematic Palaeontology, 8:3-47

Caldwell, M. W. and G. L. Bell.  1995.  Halisaurus sp (Mosasauridae) from the upper Cretaceous (?Santonian) of east-central Peru, and the taxonomic utility of mosasaur cervical vertebrae  Journal of Vertebrate Paleontology, 15(3): 532-544.

Carpenter, K. 1990 Ankylosaur systematics: example using Panoplosaurus and Edmontonia (Ankylosauria: Nodosauridae) pp. 281-298 in Carpenter, K., Currie, P.J. (eds.), Dinosaur Systematics: Approaches and Persepectives: Cambridge, Cambridge University Press.

Carr T. D. and T. E. Williamson. 2000. A Review of Tyrannosauridae (Dinosauria, Coelurosauria) from New Mexico. New Mexico Museum of Natural History and Science Bulletin 17: 113�146.

Carr T. D. and T. E. Williamson. 2004. Late Maastrichtian tyrannosaurid diversity. Zoological Journal of the Linnean Society, 142:479�523.

Chatterjee, S.  1984.  A new ornithischian dinosaur from the Triassic of North America.  Naturwissenschaften 71: 630-631.

Chatterjee, S. 1993.   Shuvosaurus, a new theropod.   Research & Exploration, 9: 274-285.

Colbert, E. H; and Bird, R. T. 1954. A gigantic crocodile from the Upper Cretaceous beds of Texas. American Museum Novitates  1688: 1-22.

Coombs, W. P., Jr. 1978. The families of the ornithischian dinosaur Order Ankylosauria. Palaeontology 21:143�170.

Coombs, W. P., Jr.  1995.  A new nodosaurid ankylosaur (Dinosauria, Ornithischia) from the Lower Cretaceous of Texas. Journal of Vertebrate Paleontology 15: 298-312.

Coombs, W. P., Jr., and T. Maryaska. 1990. Ankylosauria; pp. 456-483.  in D. B. Weishampel, P. Dodson, and H. Osmlska (eds.), The Dinosauria, First Edition. University of California Press, Berkeley.

D'Emic, M. D. In press. Revision of the sauropod dinosaurs of the Early Cretaceous Trinity Group, southern USA, with the description of a new genus. Journal of Systematic Palaeontology.

D'Emic, M.D. and B.Z. Foreman, B.Z. (2012). "The beginning of the sauropod dinosaur hiatus in North America: insights from the Lower Cretaceous Cloverly Formation of Wyoming." Journal of Vertebrate Paleontology, 32(4): 883-902

Eddy,  D. R. and Clarke J. A.  2011. New Information on the cranial anatomy of Acrocanthosaurus atokensis and its implications for the phylogeny of Allosauroidea (Dinosauria: Theropoda). PLoS ONE 6(3): e17932. doi:10.1371/journal.pone.0017932

Erickson, G. M. and Brochu, C. A. 1999.How the 'terror crocodile' grew so big. Nature 398: 205-206.

Farlow, J. O.,  Pittman, J. G., and Hawthorne, J. M., 1989.   Brontopodus birdi, Lower Cretaceous sauropod footprints from the U.S. Gulf Coastal Plain. Pp. 371�394, in Gillette, D. D.; and Lockley, M. G. (eds.), Dinosaur tracks and traces: Cambridge University Press, Cambridge.

Farke, A.  A.  2002.  A review of Torosaurus (Dinosauria: Ceratopsidae) specimens from Texas and New Mexico.  Journal of Vertebrate Paleontology 22(3 Supplement):52A.

Farke A. A., 2011 Anatomy and taxonomic status of the chasmosaurine ceratopsid Nedoceratops hatcheri from the Upper Cretaceous Lance Formation of Wyoming, U.S.A. PLoS ONE 6(1): e16196. doi:10.1371/journal.pone.0016196

Forster, C. A.,  P. C. Sereno, T. W. Evans, and T. Rowe. 1993.  A complete skull of Chasmosaurus mariscalensis (Dinosauria: Ceratopsidae) from the Aguja Formation (Late Campanian) of west Texas.  Journal of Vertebrate Paleontology 13:161-170.

Fowler, D.W. and Sullivan, R.M. 2011. The first giant titanosaurian sauropod from the Upper Cretaceous of North America. Acta Palaeontologica Polonica 56: 685�690.

Gates, T. A. and S. D. Sampson.  2007   A new species of Gryposaurus (Dinosauria: Hadrosauridae) from the late Campanian Kaiparowits Formation, southern Utah, USA.  Zoological Journal of the Linnean Society, 151:351�376.

Gilmore, C. W. 1922.  A new sauropod dinosaur from the Ojo Alamo Formation of New Mexico, Smithsonian Miscellaneous Collections 72 (14):1�9.

Harris, J. D.  1998.  A reanalysis of Acrocanthosaurus atokensis, its phylogenetic status, and paleobiogeographic implications, based on a new specimen from Texas.    New Mexico Museum of Natural History and Science, Bulletin 13: 1-75.

Hawthorne, J. M.  1990.  Dinosaur track-bearing strata of the Lampassos Cut Plain and Edwards Plateau, Texas.  Baylor Geological Studies, Bulletin 49:1-46.

Hawthorne, J. M., R. M. Bonem, J. O. Farlow, and J. O. Jones.  2002.  Ichnology, stratigraphy, and paleoenvironment of the Boerne Lake spillway dinosaur tracksite, South-central Texas.  Texas Journal of Science, 54: 309-324.

Heckert, A. B. and S .G. Lucas.  1999.  A new aetosaur from the Upper Triassic of Texas and the phylogeny of aetosaurs.   Journal of Vertebrate Paleontology, 19:50�68.

Head, J. J. 1998.  A new species of basal hadrosaurid (Dinosauria, Ornithischia) from the Cenomanian of Texas.  Journal of Vertebrate Paleontology, 18:718-738).

Holland, W. J. 1909. Deinosuchus hatcheri, a new genus and species of crocodile from the Judith River beds of Montana. Annals of the Carnegie Museum 6: 281�294.

Hunt, A. and S. Lucas.  1993.  Cretaceous vertebrates of New Mexico.   in Vertebrate Paleontology in New Mexico.  New Mexico Museum of Natural History and Science Bulletin 2:  77-91.

Hunt, A. and S. Lucas.  1994.  Ornithischian dinosaurs from the Upper Triassic of  the United States. pp. 226-241 in (Fraser, N. C. and H. D. Sues, eds.) In the shadow of dinosaurs, Early Mesozoic tetrapods.  Cambridge University Press.

Hunt, A., S. Lucas, A. Heckert, R. Sullivan, and M. Lockley.  1998.   Late Triassic dinosaurs from the western United States.  Geobios, 31:511-531.

Hunt, R. K. and T. M. Lehman.  2008.  Attributes of the ceratopsian dinosaur Torosaurus, and new material from the Javelina Formation (Maastrichtian) of Texas.  Journal of Paleontology, 82:1127-1138.

Irmis, R. B. 2005. The vertebrate fauna of the Upper Triassic Chinle Formation in northern Arizona. p. 63-88 in  S. J. Nesbitt, W. G. Parker, and R. B. Irmis (eds.) Guidebook to the Triassic formations of the Colorado Plateau in northern Arizona: geology, paleontology, and history. Mesa Southwest Museum, Bulletin 9.

Irmis, R. B., Parker, W. G., Nesbitt, S. J., Liu, J. 2007. Early ornithischian dinosaurs: the Triassic record. Historical Biology 19:3-22.

Jacobs, L. L.,  1995. Lone Star Dinosaurs. Texas A&M University Press.

Jacobs, L. L. and D. A. Winkler.  1998.  Mammals, archosaurs, and the early to late Cretaceous transition in North-Central Texas.   in Tomida, Y., Flynn, L. J., and Jacobs, L. L. (eds.), Advances in vertebrate paleontology and geochronology. National Science Museum, Tokyo, Monographs, 14:253-280.

Jacobs, L. L., Winkler, D. A., Murry, P. A., and Maurice, J. M. 1994.   A nodosaurid scuteling from the Texas shore of the Western Interior Seaway.   p. 337-346 in (Carpenter, K., Hirsch, K. F., and Horner, J. R., eds) Dinosaur eggs and babies. Cambridge University Press, Cambridge.

Jasinski, S. E., and R. M. Sullivan. 2011. Re-evaluation of pachycephalosaurids from the Fruitland-Kirtland transition (Kirtlandian, Late Campanian), San Juan Basin, New Mexico, with a description of a new species of Stegoceras and a reassessment of Texacephale langstoni. In: R. M. Sullivan et al. (editors), Fossil Record 3: New Mexico Museum of Natural History and Science, Bulletin. 53:202-215.

Kellner, A.W.A. and Langston, W., Jr. 1996. Cranial remains of Quetzalcoatlus (Pterosauria, Azhdarchidae) from the Late Cretaceous sediments of Big Bend National Park, Texas. Journal of Vertebrate Paleontology 16: 222-231. 

Kuban, G. J.  1989.  Color distinctions and other curious features of dinosaur tracks near Glen Rose, Texas.  p. 427-440 in Gillette, D. D. and Lockley, M. G., (eds.),  Dinosaur tracks and traces.  Cambridge Univ. Press, Cambridge.

Langston, W. L., Jr. 1973. The crocodilian skull in historical perspective; pp. 263–284 in C. Gans and T. S. Parsons (eds.), Biology of the Reptilia, Volume 4. Academic Press, New York.

Langston, W.  1974.  Nonmammalian Comanchean tetrapods.   Geoscience and Man 8:77-102.

Lawson, D.A. 1975. Pterosaur from the latest Cretaceous of West Texas. Discovery of the largest flying creature. Science, 187: 947-948.

Lawson, D. A.  1976.  Tyrannosaurus and Torosaurus, Maastrichtian dinosaurs from Trans-Pecos, Texas.  Journal of Paleontology, 50: 158-164.

Lee, Y.-N. 1996. A new nodosaurid ankylosaur (Dinosauria, Ornithischia) from the Paw Paw Formation (late Albian) of Texas. Journal of Vertebrate Paleontology 16:232-245.

Lee, Y.-N. 1997. The Archosauria from the Woodbine Formation (Cenomanian) in Texas. Journal of Paleontology 71:1147-1156.

Lee, Y.-N.  1997.   Bird and dinosaur footprints in the Woodbine Formation (Cenomanian), Texas.  Cretaceous Research,  18:849-864.

Lehman, T. H.. 1989.  Chasmosaurus mariscalensis, sp. nov., a new ceratopsian dinosaur from Texas.   Journal of Vertebrate Paleontology,  9:137-162.

Lehman, T. M. 1996.   A horned dinosaur from the El Picacho Formation of West Texas, and review of ceratopsian dinosaurs from the American Southwest.   Journal of Paleontology, 70:494-508.

Lehman, T. M. 1998.  A gigantic skull and skeleton of the horned dinosaur Pentaceratops sternbergi from New Mexico.  Journal of Paleontology,   72: 894-906.

Lehman, T. M. 2010. Pachycephalosauridae from the San Carlos and Aguja Formations (Upper Cretaceous) of West Texas, and observations of the frontoparietal dome. Journal of Vertebrate Paleontology, 30:786-798.

Lehman, T. M. and Coulson, A. B.  2002.  A juvenile specimen of the sauropod dinosaur Alamosaurus sanjuanensis from the Upper Cretaceous of Big Bend National Park, Texas.   Journal of Paleontology, 76: 156-172 .

Lehman, T. M., F. W. McDowell and J. N. Connelly. 2006. First isotopic (U-Pb) age for the Late Cretaceous Alamosaurus vertebrate fauna of West Texas, and its significance as a link between two faunal provinces. Journal of Vertebrate Paleontology 26:922�928.

Lockley, M. and A. P. Hunt.  1995.  Dinosaur tracks and other footprints of the western United States.  Columbia University Press, New York.  338 pp.

Long, R. L. and P. A. Murry.  1995.  Late Triassic (Carnian and Norian) tetrapods from the southwestern United States.  New Mexico Museum of Natural History and Science, Bulletin 4: 1-254.

Longrich, N. R., J. Sankey, and D. Tanke.  2010. Texacephale langstoni, a new genus of pachycephalosaurid (Dinosauria: Ornithischia) from the upper Campanian Aguja Formation, southern Texas, USA.  Cretaceous Research, 31: 274-284

Lucas, S.G., Sullivan, R.M., Hunt, A.P., 2006, Re-evaluation of Pentaceratops and Chasmosaurus (Ornithischia, Ceratopsidae) in the Upper Cretaceous of theWestern Interior, in Lucas, S. G. and Sullivan, R.M., (eds.) Late Cretaceous vertebrates from the Western Interior. New Mexico Museum of Natural History and Science Bulletin 35:367-370.

Lundelius, E. L.  1986. Vertebrate Paleontology of the Balcones Fault trend.  p. 41-50 in Abbott, Patrick L. and Woodruff, C. M., Jr. (eds.), The Balcones Escarpment, Central Texas: Published for Geological Society of America Annual Meeting San Antonio, Texas November 9-14, 1986.

Main, D. J. and A. Fiorillo.  2002 . Report of a new Platypterygius (Reptilia: Ichthyosauria) specimen from the Lower Cretaceous rocks of Tarrant County, TX. Journal of Vertebrate Paleontology 22(3):82A (supplement).

Main, D.  and A. Fiorillo.  2003.  Report of new Cenomanian hadrosaur (Dinosauria: Ornithischia) postcrania from the Woodbine Formation of North Central Texas.  Journal of Vertebrate Paleontology. 23(3 Supplement):75A.

Martil, D. M., and D. Naish. 2006. Cranial crest development in the Azhdarchoid pterosaur Tupuxuara, with a review of the genus and tapejarid monophyly Palaeontology, v. 49, part 4, p. 925-941.

Martz, J. W. and B. J. Small. 2006. Tecovasuchus chatterjeei, a new aetosaur (Archosauria: Stagonolepididae) from the Tecovas Formation (Carnian, upper Triassic) of Texas.  Journal of Vertebrate Paleontology 26:308�320.

Milne, D. H. and Schafersman, S. D.  1983.  Dinosaur tracks, erosion marks and midnight chisel work (but no human footprints) in the Cretaceous limestone of the Paluxy River bed, Texas.  Journal of Geological Education,  31: 111-123.

Murry, P.  1986.  Vertebrate paleontology of the Dockum Group, western Texas and eastern New Mexico.  pp. 109-137 in K. Padian (ed.), The beginning of the age of dinosaurs; Faunal change across the Triassic-Jurassic boundary. Cambridge University Press, Cambridge, England.

Murry, P. A., D. A. Winkler, and L. L. Jacobs. 1991.  An azhdarchid pterosaur humerus from the Lower Cretaceous Glen Rose Formation of Texas.  Journal of Paleontology 65:  167-170.

Myers, T. S.. 2010a. A new ornithocheiroid pterosaur from the Upper Cretaceous (Cenomanian-Turonian) Eagle Ford Group of Texas. Journal of Vertebrate Paleontology 30(1):280-287.

Myers, T. S.. 2010b. Earliest Occurrence of the Pteranodontidae (Archosauria: Pterosauria) in North America: New Material from the Austin Group of Texas. Journal of Paleontology 84(6):1071-1081.

Myers, T. S. and A. R. Fiorillo. 2009. Evidence for gregarious behavior and age segregation in sauropod dinosaurs.  Palaeogeography,Palaeoclimatology, Palaeoecology, 274:96-104.

Nesbitt, S. J. 2011. The early evolution of archosaurs: Relationships and the origin of major clades. Bulletin of the American Museum of Natural History, 352:1-292.

Nesbitt, S. J. and M. A. Norell.  2006.  Extreme convergence in the body plans of an early suchian (Archosauria) and ornithomimid dinosaurs (Theropoda).  Proceedings of the Royal Society B: Biological Sciences,  273:1045-1048.

Nesbitt, S. J., R. B. Irmis, and W. G. Parker. 2007. A critical reevaluation of the Late Triassic dinosaur taxa of North America. Journal of Systematic Palaeontology 5(2):209-243

Parker, W. G.  2005.  A new species of the Late Triassic aetosaur Desmatosuchus (Archosauria: Pseudosuchia).  Comptes Rendus Palevol, 4:327-340.

Parker, W. G., M. R. Stocker, and R. B. Irmis. 2008. A new desmatosuchine aetosaur (Archosauria; Suchia) from the Upper Triassic Tecovas Formation (Dockum Group) of Texas. Journal of Vertebrate Paleontology, 28: 692-701.

Polcyn, M. J. and G. L. Bell.  2005a.  The rare mosasaur genus Globidens from North Central Texas (Mosasaurinae:Globidensini).  Journal of Vertebrate Paleontology, 25 (3 Supplement):101A.

Polecyn, M. J. and G. L. Bell.  2005b. Russellosaurus coheni n. gen., n. sp., a 92 million-year-old mosasaur from Texas (USA), and the definition of the parafamily Russellosaurina  Netherlands Journal of Geosciences, Geologie en Mijnbouw, 8:321-333.

Rauhut, O. 1997. Zur Sch�delanatomie von Shuvosaurus inexpectatus (Dinosauria, Theropoda). In: Sachs, S., Rauhut, O. W. M. and Weigert, A. (eds), Erstes Treffen der deutschsprachigen Palaeoherpetologen. Extended Abstracts. Terra Nostra. 97/9: 17-21

Rodrigues, T. and Kellner, A. W. A. 2008. Review of the pterodactyloid pterosaur Coloborhynchus. Zitteliana B 28: 219�228.

Rogers, J. V., II.  2000.  A complete crocodiloid egg from the Lower Cretaceous (Albian) Glen Rose Formation, central Texas.  Journal of Vertebrate Paleontology, 20:780-783.

Rogers, J. V., II.  2002.  Theropod dinosaur trackways in the Lower Cretaceous (Albian) Glen Rose Formation, Kinney County, Texas.  Texas Journal of Science, 54:133-142.

Rogers, J. V., II.  2003.  Pachycheilosuchus trinquei, a new procoelous crocodyliform from the Lower Cretaceous (Albian) Glen Rose Formation of Texas.  Journal of Vertebrate Paleontology, 23:128-145.

Rose, P. J., 2007. A new titanosauriform sauropod (Dinosauria: Saurischia) from the Early Cretaceous of Central Texas and its phylogenetic relationships. Palaeontologia Electronica Vol. 10, Issue 2; 8A:65p, 2.6MB; http://palaeo-electronica.org/paleo/2007_2/00063/index.html (PDF: 65 pages)

Rowe, T., R. L. Cifelli, T. M. Lehman, and A. Weil.  1992.  The Campanian Terlingua Local Fauna, with a summary of other vertebrates from the Aguja Formation, Trans-Pecos Texas. Journal of Vertebrate Paleontology, 12: 472-493.

Sankey, J. T.  2001.  Late Campanian southern dinosaurs, Aguja Formation, Big Bend, Texas.  Journal of Paleontology 75:208-215.

Sankey, J. T.  2008.  Vertebrate paleoecology from microsites, Talley Mountain, upper Aguja Formation (Late Cretaceous), Big Bend National Park, Texas.  in  Sankey, J.T. and S. Baszio, eds. Vertebrate Microfossil Assemblages Their Role in Paleoecology and Paleobiogeography. Indiana University Press.

Scannell, J. B. and J. R. Horner.  2010.  Torosaurus Marsh, 1891, is Triceratops Marsh, 1889 (Ceratopsidae: Chasmosaurinae): synonymy through ontogeny.  Journal of Vertebrate Paleontology, 30:1157-1168.

Schwimmer, D. R.  2002. King of the Crocodylians: The Paleobiology of Deinosuchus.  Indiana University Press, Bloomington, 240 pp.

Small, B. J.  1989.  Aetosaurs from the Upper Triassic Dockum Formation, Post Quarry, West Texas. In: S.G. Lucas and A.P. Hunt, Editors, Dawn of the age of dinosaurs in the American Southwest, University of New Mexico Press, Albuquerque, pp. 301�308.

Small, B. J.  2002.  Cranialanatomy of Desmatosuchus haplocerus (Reptilia: Archosauria: Stagonolepididae).   Zoological Journal of the Linnean Society 136:97�111.

Stocker, M. R. (2010), A new taxon of phytosaur (Archosauria: Pseudosuchia) from the Late Triassic (Norian) Sonsela Member (Chinle Formation) in Arizona, and a critical reevaluation of Leptosuchus Case, 1922. Palaeontology, 53:�997�1022.

Storrs, G. W.  1981.  A review of occurrences of the Plesiosauria (Reptilia: Sauropterygia) in Texas, with description of new material.  Unpublished M.A. thesis.  University of Texas at Austin.  (abstract published in Journal of Vertebrate Paleontology, 1983, 2(4):486.)

Sullivan, R M., A. C. Boere, and S. G. Lucas,  2005.  Redescription of the ceratopsid dinosaur Torosaurus utahensis (Gilmore, 1946) and a revision of the genus.  Journal of Paleontology 79: 564-582

Thurmond, J. 1968. A new polycotylid plesiosaur from the Lake Waco Formation (Cenomanian) of Texas. Journal of Paleontology 42:1289-1296.

Tidwell, V, and K. Carpenter.  2003. Braincase of an Early Cretaceous titanosauriform sauropod from Texas.  Journal of Vertebrate Paleontology, 23:176-180.

Tykoski, R. S. and Fiorillo, A. R. 2010. An enantiornithine bird from the lower middle Cenomanian of Texas. Journal of Vertebrate Paleontology, 30:288-292.

Vickaryous, M. K. 2006. New information on the cranial anatomy of Edmontonia rugosidens Gilmore, a Late Cretaceous nodosaurid dinosaur from Dinosaur Provincial Park, Alberta. Journal of Vertebrate Paleontology 26, 1011-1013.

Wagner, J. R. and T. Lehman. 2001. A new species of Kritosaurus from the Cretaceous of Big Bend National Park, Brewster County, Texas. Journal of Vertebrate Paleontology 21 (Suppl.): 110A�111A.

Wagner, J. R. and T. Lehman. 2009. An enigmatic new lambeosaurine hadrosaur (Reptilia: Dinosauria) from the Upper Shale Member of the Campanian Aguja Formation of Trans-Pecos Texas�. Journal of Vertebrate Paleontology 29: 605-611.

Wedel, M. J, R. L. Cifelli, and P. K. Sanders.  2000.  Sauroposeidon proteles, a new sauropod from the early Cretaceous of Oklahoma.  Journal of Vertebrate Paleontology 20:109-114.

Wedel, M. J. and  R. L. Cifelli.  2006.  Sauroposeidon: Oklahoma�s Native Giant.  Oklahoma Geology Notes 65:40-57.

Weinbaum, J.C.  2011. The skull of Postosuchus kirkpatricki (Archosauria: Paracrocodyliformes) from the Upper Triassic of the United States. PaleoBios 30:

Weinbaum, J. C.  and Hungerbuhler, A. 2007. A revision of Poposaurus gracilis (Archosauria: Suchia) based on two new specimens from the Late Triassic of the southwestern U.S.A. - Palaontologische Zeitschrift, 81: 131-145.

Weinbaum, J. C. 2011. The skull of Postosuchus kirkpatricki (Archosauria: Paracrocodyliformes) from the Upper Triassic of the United States. PaleoBios 30:18-44

Weishampel, D. B.  1990.  Dinosaur distribution. pp. 63-140 in Weishampel, D. B.,  P. Dodson, and H. Osm�lska. (eds.). The Dinosauria. University of California Press, Berkeley.

Weishampel, D. B. and J. R. Horner. 1990.  Hadrosauridae. pp. 534-561 in Weishampel, D. B.,  P. Dodson, and H. Osm�lska. (eds.). The Dinosauria. University of California Press, Berkeley.

Welles, S. P. 1949. A new elasmosaur from the Eagle Ford Shale of Texas. Fondren Science Series, Southern Methodist University 1:1-28.

Winkler, D. A.,  Jacobs, L. L., Lee, Y-N., and Murry, P. A. 1995.  Sea level fluctuation and terrestrial faunal change in north-central Texas.  Sixth symposium on Mesozoic terrestrial ecosystems and biota; short papers. p. 175-177

Winkler, D. A.,  Jacobs, L. L., Branch, J. R., Murry, P. A., Downs, W. R., and Trudel, P.. 1988.  The Proctor Lake dinosaur locality, lower Cretaceous of Texas.  Hunteria, 12: 1-8.

Winkler, D. and P. A. Murry. 1989.  Paleoecology and hypsilophodontid behavior at the Proctor Lake dinosaur locality (early Cretaceous) Texas.  Geological Society of America, Special Paper 238:55-61.

Winkler, D. A, Murry, P. A., and Jacobs, L. L.  1990.  Early Cretaceous (Comanchean) vertebrates of central Texas.  Journal of Vertebrate Paleontology,  10:. 95-116.

Winkler, D.,  P. A. Murry, and L. L. Jacobs. 1997.  A new species of Tenontosaurus (Dinosauria, Ornithopoda) from the early Cretaceous of Texas.  Journal of Vertebrate Paleontology, 17:330-348.

Woodward, H. N. and Lehman, T. M. 2009. Bone histology and micro-anatomy of Alamosaurus sanjuanensis (Sauropoda: Titanosauria) from the Maastrichtian of Big Bend National Park, Texas. Journal of Vertebrate Paleontology 29: 807�821.

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