Andrew B. Heckert Ph.D.

Dr. Heckert comes to Appalachian State from the New Mexico Museum of Natural History & Science, where he worked for three years after completing his Ph.D. Over the last 12 years Dr. Heckert has worked extensively on the vertebrate paleontology and stratigraphy of the American Southwest, collecting fossils ranging in age from Devonian to Pleistocene, but focusing primarily on the Upper Triassic strata of Texas, New Mexico, and Arizona.

There are 122 included publications by Andrew B. Heckert Ph.D.:

TitleDateViewsBrief Description
Acaenasuchus geoffreyi (Archosauria:Aetosauria) from the Upper Triassic Chinle Group: Juvenile of Desmatosuchus haplocerus 2002 2358 Aetosaur scutes assigned to Acaenasuchus geoffreyi Long and Murry, 1995, are juvenile scutes of Desmatosuchus haplocerus (Cope, 1892), so A. geoffreyi is a junior subjective synonym of D. haplocerus. Scutes previously assigned to Acaenasuchus lack an...
Aetosaurs (Archosauria:Stagonolepididae) from the Upper Triassic (Revueltian) Snyder Quarry 2003 2134 Two species of aetosaurs are known from the Snyder quarry (NMMNH locality 3845): Typothorax coccinarum Cope and Desmatosuchus chamaensis Zeigler, Heckert, and Lucas. Both are represented entirely by postcrania, principally osteoderms (scutes), but a...
Arizona’s Jurassic Fossil Vertebrates and the Age of the Glen Canyon Group 2005 6387 Most fossil vertebrates of Jurassic age from Arizona are derived from the Glen Canyon Group on the southern Colorado Plateau in the northeastern part of the state. Glen Canyon Group strata of Jurassic age in Arizona that yield fossils include the up...
Bibliography of Arizona vertebrate paleontology 2005 1811 We provide a bibliography of Arizona vertebrate paleontology that consits of approximately 625 references covering vertebrate occurrences ranging in age from Devonian to Holocene. Not surprisingly, references to Triassic and Neogene vertebrates are ...
Body mass estimates of phytosaurs (Archosauria: Parasuchidae) from the Petrified Forest Formation (Chinle Group: Revueltian) based on skull and limb bone measurements. 2003 2302 Phytosaurs were the largest and most common semi-aquatic predators of the Late Triassic. Although their skulls are relatively common in the fossil record, articulated, or even associated skeletons are extremely rare, so it has always been difficult ...
The carpus and tarsus of the early Permian synapsid Sphenacodon ferox (Eupelycosauria: Sphenacodontidae) 2005 3568 The carpus and tarsus of the sphenacodontid synapsid Sphenacodon ferox are described in detail for the first time on the basis of nearly complete, loosely articulated examples from an incomplete, partially articulated skeleton from the Lower Permian ...
Coelophysids (Dinosauria: Theropoda) from the Upper Triassic (Revueltian) Snyder Quarry 2003 2497 The Snyder quarry preserves one of the richest assemblages of Norian theropods in the world, and the second-most productive theropod locality in the Chinle Group. At least four coelophysid theropods are preserved at the Snyder quarry, based on tibia...
Correlation of Triassic Strata Across the Rio Grande Rift, North-Central New Mexico 1999 1089 Middle Triassic strata of the Moenkopi Formation and Upper Triassic strata of the Chinle Group are correlated from the Colorado Plateau eastward across the northern Rio Grande rift to the southern High Plains of eastern New Mexico. This correlation...
Cretaceous dinosaurs in New Mexico 2000 6011 New Mexico's most extensive fossil record of dinosaurs is from rocks of Cretaceous age. The Early Cretaceous record is confined to tracks of late Albian age, principally from northeastern NM. They are primarily of ornithopods (Caririchnium, Amblyda...
Definition and Correlation of the Lamyan: A New Biochronological Unit for the Nonmarine Late Carnian (Late Triassic) 2005 2461 The Sonsela Member of the Petrified Forest Formation at Petrified Forest, Arizona and the Tres Lagunas Member of the Santa Rosa Formation in east-central New Mexico yield vertebrate fossil assemblages (faunas) that are intermediate in composition bet...
Dental morphology of the hybodontoid shark Lonchidion humblei Murry from the Upper Triassic Chinle Group, USA 2007 1342 We describe the morphology and histological structure of the teeth of the hybodontoid shark Lonchiodion humblei from the Upper Triassic Chinle Group in Texas and New Mexico. The five morphotypes (symphyseal, mesial, anterolateral, lateral and posteri...
Diminutive metoposaurid skulls from the Upper Triassic Blue Hills (Adamanian:latest Carnian) of Arizona 2002 1120 We describe two tiny metoposaurid specimens from the lower part of the Chinle Group in the Blue Hills of east-central Arizona. The more complete of these specimens is an incomplete skull anterior to the orbits (45 mm preorbitallength) and numerous s...
Dinosaurs of New Mexico: An overview 2000 3858 New Mexico is in the forefront of dinosaur-collecting grounds. AnalysiS of the state's dinosaur fossils has been far reaching, touching upon every aspect of dinosaur paleontology, including biogeography, biostratigraphy, functional morphology, paleoe...
Dinosaurs of New Mexico: A Popular Guide 2000 3543 This article provides information on the popular side of New Mexico's dinosaurs. It summarizes dinosaur exhibits in New Mexico, provides advice on collecting dinosaur fossils in the state and lists key published books that contain information on New ...
Distribution, age and correlation of Cretaceous fossil vertebrates from Arizona 2005 5308 Fossil vertebrates of Cretaceous age are known from two principal areas in Arizona—the Lower and Upper Cretaceous strata of the Basin and Range of southeastern Arizona and the Upper Cretaceous strata of the Black Mesa Basin on the Colorado Plateau ...
Diverse New Microvertebrate Assemblage from the Upper Triassic Cumnock Formation, Sanford Subbasin, North Carolina, USA 2012 1705 The Moncure microvertebrate locality in the Cumnock Formation, Sanford sub-basin, North Carolina, dramatically increases the known Late Triassic age vertebrate assemblage from the Deep River Basin. The 50,000 recovered microvertebrate fossils include...
An early eubrachyuran (Malacostraca: Decapoda) from the Upper Triassic Snyder quarry, Petrified Forest Formation, north-central New Mexico 2003 2179 New Mexico Museum of Natural History and Science (NMMNH) locality L-3845 in the Petrified Forest Formation of the Chinle Group (Rio Arriba County, NM) yields nonmarine fossil vertebrates, invertebrates, and plants of Revueltian (early-mid Norian, ~2...
Early Permian Vertebrate Assemblage and Its Biostratigraphic Significance, Arroyo del Agua, Rio Arriba County, New Mexico 2005 4067 Early Permian vertebrate fossils from the upper part of the El Cobre Canyon Formation of the Cutler Group in the area around Arroyo del Agua, Rio Arriba County, New Mexico, encompass an extensive assemblage of chondrichthyans, osteichthyans, temnos...
First Report On Reptile Tracks From The Moenkopi Formation (Lower-Middle Triassic) In Dinosaur National Monument, Utah 2014 1578 On the Colorado Plateau, numerous Mesozoic stratigraphic units, including the Navajo and Entrada formations, preserve abundant tracks that contrast with their extremely poor body fossil records. This is also true of the Moenkopi Formation, which also...
Geology and Paleontology of the Upper Jurassic (Morrison Formation: Brushy Basin Member) Peterson Quarry, Central New Mexico 2003 8378 The Upper Jurassic Peterson quarry, located in Bernalillo County, central New Mexico, is New Mexico’s most extensive and productive Jurassic dinosaur locality. The quarry is developed in the upper part of the Brushy Basin Member of the Morrison Form...
Geology of early Permian tracksites, Robledo Mountains, south-central New Mexico. 1995 3300 Early Permian fossil localities, including numerous tracksites, in the southern Robledo Mountains of Dofia Ana County, New Mexico cover an area of approximately 20 km [superscript]2 Detailed mapping and measurement of seven stratigraphic sections sh...
A Giant Phytosaur (Reptilia: Archosauria) Skull from the Redonda Formation (Upper Triassic: Apachean) of East-Central New Mexico 2001 3466 In the Summer of 1994, a field party of the New Mexico Museum of Natural History and Science (NMMNH) collected a giant, incomplete phytosaur skull from a bonebed discovered by Paul Sealey in east-central New Mexico. This bonebed lies in a narrow cha...
A giant skull, ontogenetic variation and taxonomic validity of the Late Triassic phytosaur Parasuchus 2007 1715 Parasuchus (= Paleorhinus) is the most primitive known phytosaur, and its fossils define a Carnian biochron recognizable across much of Pangea. The largest known specimen of this primitive taxon, an incomplete skull from the Popo Agie Formation in n...
Global Triassic tetrapod biostratigraphy and biochronology: 2007 status 2007 1748 The global Triassic timescale based on tetrapod biochronology remains a robust tool for both global and regional age assignment and correlation. The Lootsbergian and Nonesian land-vertebrate faunachrons (LVFs) are of Early Triassic age; cross correl...
Glyptops (Testudines, Pleurosternidae) from the Upper Jurassic Morrison Formation, New Mexico 2006 3560 We document an incomplete turtle carapace and plastron from the Peterson quarry in the Brushy Basin Member of the Upper Jurassic Morrison Formation, Bernalillo County, New Mexico. This is the first non-dinosaurian vertebrate from the Peterson quarry ...
Grooves to Tubes: Evolution of the Venom Delivery System in a Late Triassic “reptile” 2010 689 Venom delivery systems occur in a wide range of extant and fossil vertebrates and are primarily based on oral adaptations. Teeth range from unmodified (Komodo dragons) to highly specialized fangs similar to hypodermic needles (protero- and solenoglyp...
Ichthyoliths and Other Microvertebrate Remains from The Morrison Formation (Upper Jurassic) of Northeastern Wyoming: A Screen-Washed Sample Indicates A Significant Aquatic Component to the Fauna 2011 2037 A screenwashed microvertebrate site, the Mile 175 locality, in the Morrison Formation of Wyoming has yielded more than 3000 elements of actinopterygian fish and indicates that fish were not as rare in some parts of the formation as previously suppose...
An illustrated atlas of the phytosaur (Archosauria: Parasuchidae) postcrania from the Upper Triassic Snyder quarry (Petrified Forest Formation, Chinle Group) 2003 2196 The Upper Triassic Snyder quarry of north-central New Mexico yields the remains of numerous individuals of the phytosaur Pseudopalatus buceros, as well as other vertebrates. The majority of the phytosaurian skeletal elements in the quarry are associa...
Instar sizes and growth in the Middle Permian monuran Dasyleptus brongniarti (Insecta: Machilida: Dasyleptidae) 2005 2934 We used probability plotting to identify six sequential instars in the monuran Dasyleptus brongniarti Sharov, 1957. Data from 25 specimens from the Middle Permian (Ufimian) Kaltan locality in the Kuznetsk Formation in southwestern Siberia were used i...
Intraspecific Variation in Aetosauroides scagliai Casamiquela (Archosauria: Aetosauria) from the Upper Triassic of Argentina and Brazil: An Example of Sexual Dimorphism? 2015 829 Aetosaurs are a group of quadrupedal, armoured pseudosuchian archosaurs from the Upper Triassic. They are characterized by dorsal and ventral carapaces, and appendicular osteoderms, all of them ornamented. Aetosaurs have been proposed as index fossil...
Invertebrate paleontology of the Upper Triassic Snyder quarry, Chinle Group, Chama basin. 2003 1859 The Snyder quarry in the Chama basin of north-central New Mexico is stratigraphically high in the Petrified Forest Formation of the Chinle Group and of Revueltian (Norian) age. Besides an extensive fossil vertebrate assemblage, the quarry yields a sm...
Jurassic Dinosaurs in New Mexico 2000 3286 New Mexico has a sparse but growing record of Jurassic dinosaurs. The oldest records are theropod footprints and a sauropod vertebra from the Middle-Upper Jurassic Summerville Formation. The footprints are part of a widespread large theropod-pteros...
Jurassic Stratigraphy in West-Central New Mexico 2003 4518 Jurassic strata in west-central New Mexico encompass part of the southern edge of the Jurassic outcrop belt in the Western Interior. Some of the Jurassic units pinch out or are truncated southward in west-central New Mexico, so that in the southernmo...
Krzyzanowskisaurus, a new name for a probable ornithischian dinosaur from the Upper Triassic Chinle Group, Arizona and New Mexico, USA. 2005 3102 Recent discoveries have demonstrated that Revueltosaurus callenderi Hunt is not an ornithischian dinosaur, so it is probably not congeneric with the putative ornithischian Revueltosaurus hunti Heckert. Revueltosaurus Hunt, 1989 is the senior generic ...
A Large Archosauriform Tooth with Multiple Supernumerary Carinae from the Upper Triassic of New Mexico (USA), with Comments on Carina Development and Anomalies in the Archosauria 2009 3337 Here we report a tooth of a large archosauriform from the Upper Triassic of New Mexico, USA that displays developmental anomalies of carina formation. This tooth has two supernumerary carinae, both on the lingual side of the tooth. Previously, carina...
A Late Cretaceous Mosasaur from North-Central New Mexico 1995 2563 We describe a partial vertebral column of a mosasaur identified as cf. Tylosaurus sp. from the lower Niobrara interval of the Mancos Shale south of Galisteo in Santa Fe County, New Mexico. Invertebrate fossils collected from the same horizon includ...
The Late Cretaceous Tucson Mountains Dinosaur 2005 2224 Historically, the “Tucson Mountains dinosaur” has been considered an Early Cretaceous iguanodont from a megabreccia block of the Amole Arkose in the Tucson Mountains caldera of southern Arizona. We demonstrate here that it is instead a large hadrosa...
The Late Triassic aetosaur Paratypothorax 2006 3200 Paratypothorax is a Late Triassic aetosaur known from Germany, Greenland, North Africa and the American Southwest. The few records in Germany are from the Stubensandstein, whereas the American recordshave a much longer stratigraphic range. The genus...
The Late Triassic Archosauromporph Trilophosaurus as an Arboreal Climber 2005 1279 Two species of the unusual archosauromorph Trilophosaurus, T buettneri Case and T jacobsi Murry, are known from diverse localities in the Upper Triassic Chinle Group in the southwestern USA. Both species likely occupied similar ecological niches, bas...
The Late Triassic Canjilon quarry (upper Chinle Group, New Mexico) phytosaur skulls: Evidence of sexual dimorphism in phytosaurs. 2002 2434 The Canjilon quarry, located in north-central New Mexico near Ghost Ranch, is a death assemblage of phytosaurs stratigraphically high in the Petrified Forest Formation of the Chinle Group (Revueltian = early-mid Norian). The site yields numerous foss...
The Late Triassic Snyder Quarry: A brief history of discovery and excavation 2003 2115 Following Mark Snyder’s discovery of NMMNH locality 3845, the “Snyder quarry,” in June, 1998, we directed no fewer than five major and several minor excavations at the quarry, recovering more than 60 jackets and hundreds of isolated elements from Ju...
The Late Triassic timescale: Age and correlation of the Carnian–Norian boundary 2012 3216 The Late Triassic timescale is poorly constrained due largely to the dearth of reliable radio-isotopic ages that can be related precisely to biostratigraphy combined with evident contradictions between bio-stratigraphic and magnetostratigraphic corre...
Lower Chinle Group (Upper Triassic:Carnian) stratigraphy in the Zuni Mountains, west-central New Mexico 2002 2529 The lower Chinle Group in the Zuni Mountains consists of (ascending) the mottled strata, Shinarump Formation, Bluewater Creek Formation, and the Blue Mesa Member of the Petrified Forest Formation. A persistent, bench-forming sandstone that crops ou...
Lower Chinle Group (Upper Triassic:upper Carnian) tetrapods from the vicinity of Cameron, Arizona 2002 1316 Vertebrate fossils from the lower Chinle Group housed at the Museum of Northern Arizona (MNA) represent some of the stratigraphically lowest Upper Triassic tetrapods collected on the Colorado Plateau. Unfortunately, many of these fossils were collec...
Mandibles of Juvenile Phytosaurs (Archosaura: Crurotarsi) from the Upper Triassic Chinle Group of Texas and New Mexico, USA 2013 1236 Here we describe five specimens of juvenile phytosaurs from several localities in the Upper Triassic Chinle Group of Texas and New Mexico. These include three specimens from localities in the Tecovas Formation (Texas) of Adamanian age and one each fr...
Mandibles Of Juvenile Phytosaurs (Archosauria: Crurotarsi) From The Upper Triassic Chinle Group Of Texas And New Mexico, Usa 2013 1103 Here we describe five specimens of juvenile phytosaurs from several localities in the Upper Triassic Chinle Group of Texas and New Mexico. These include three specimens from localities in the Tecovas Formation(Texas) of Adamanian age and one each fro...
Mesozoic Stratigraphy at Durango, Colorado 2005 21237 A nearly 3-km-thick section of Mesozoic sedimentary rocks is exposed at Durango, Colorado. This section consists of Upper Triassic, Middle-Upper Jurassic and Cretaceous strata that well record the geological history of southwestern Colorado during mu...
Micro- and small vertebrate biostratigraphy and biochronology of the Upper Triassic Chinle Group, southwestern USA 2006 3330 A long-term goal of vertebrate biostratigraphers is to construct a microvertebrate biostratigraphy for lower Mesozoic rocks that complements and extends the mammal-based biostratigraphy in place for Upper Cretaceous-Recent deposits. Here we report su...
The microfauna of the Upper Triassic Ojo Huelos Member, San Pedro Arroyo Formation, central New Mexico, U.S.A. 2002 2887 Three fossiliferous horizons at the type section of the Upper Triassic Ojo Huelos Member of the San Pedro Arroyo Formation yield a microfauna of ostracodes, “spirorbids,” sharks, bony fish, and tetrapods. These fossils represent a rare lacustrine mic...
The Microvertebrate Fauna of the Upper Triassic (Revueltian) Snyder Quarry, North-Central New Mexico 2005 2966 The Snyder quarry is a well-documented assemblage of Late Triassic invertebrates and vertebrates from the Painted Desert Member of the Upper Triassic Petrified Forest Formation in the Chama Basin, north-central New Mexico. The presence of Revueltian ...
A new dinosaur footprint locality from the Dakota Sandstone (Upper Cretaceous: Cenomanian) in west-central New Mexico 1998 2214 We assign two incomplete dinosaur tracks from the Dakota Sandstone in Socorro County, west-central New Mexico to the ichnogenus Caririchnium sp., widely believed to represent the tracks of an iguanodontid ornithopod dinosaur. This is the first record...
New Occurrence of Trilophosaurus (Reptilia: Archosauromorpha) Form the Upper Triassic of West Texas and Its Biochronological Significance 2001 1416 We document a rich Upper Triassic bonebed in Borden County, Texas in either the uppermost Tecovas Formation or, more likely, the Trujillo Formation of the Chinle Group, that represents one of the highest stratigraphic occurrences of the aberrant arch...
A new species of the aetosaur Typothorax (Archosauria: Stagonolepididae) from the Upper Triassic of east-central New Mexico. 2002 2167 We describe an incomplete skeleton of a new species of the aetosaur Typothorax, T.antiquum, from the Los Esteros Member of the Santa Rosa Formation near Lamy, Santa Fe County, New Mexico. Features that diagnose T. antiquum from the type and only ot...
A new species of Desmatosuchus (Archosauria: Aetosauria) from the Upper Triassic of the Chama basin, north-central New Mexico. 2002 2487 We describe a new species of the aetosaur Desmatosuchus, D. chamaensis, from the Upper Triassic Snyder quarry, Petrified Forest Formation of the Chinle Group, Chama basin of north-central New Mexico. D. chamaensis is also present in the Bull Canyon ...
A New Species of The Enigmatic Archosauromorph Doswellia from the Upper Triassic Bluewater Creek Formation, New Mexico, USA 2012 609 Doswellia sixmilensis is a new species of the dos-welliid archosauromorph genus Doswellia named for an incomplete skeleton from the Upper Triassic Bluewater Creek Formation of the Chinle Group in west-central New Mexico, USA. D. sixmilensis differs f...
No Definitive Evidence of Paleocene Dinosaurs in the San Juan Basin 2009 1531 In a recent article in this journal, Fassett (2009) concludes that dinosaur fossils of Paleocene age are present in the San Juan Basin of New Mexico-Colorado. However, we argue that, based on existing data, Fassett has failed to produce compelling ...
Occurrence of the dinosaurian ichnogenus Grallator in the Redonda Formation (Upper Triassic: Norian) of eastern New Mexico 2000 1624 Numerous tridactyl dinosaur tracks from the Upper Triassic Redonda Formation of-eastcentral New Mexico have been referred to the ichnogenus Grallator, but most are poorly preserved specimens of the tetradactyl Pseudotetrasauropus. UMMP 16161 and MDM...
The oldest North American prosauropod, from the Upper Triassic Tecovas Formation of the Chinle Group (Adamanian: latest Carnian), West Texas. 2002 2760 An isolated tooth from the Tecovas Formation of the Chinle Group, Crosby County, West Texas, represents the oldest definitive record of a prosauropod dinosaur from North America. Its age is Adamanian (latest Carnian, approximately 225 Ma) based on ve...
Oldest records of the Late Triassic theropod dinosaur Coelophysis bauri 2007 1096 Coelophysis bauri is a well-known theropod dinosaur from the Upper Triassic of the southwestern United States. Prior to this study, it was only known from extensive remains from the Whitaker quarry, in the Rock Point Formation, of north-central New M...
Osteoderms of juveniles of Stagonolepis (Archosauria: Aetosauria) from the lower Chinle Group, east-central Arizona 2008 1995 We describe for the first time small «25 mm) dorsal paramedian, lateral, and appendicular /ventral scutes (osteoderms) of aetosaurs from the Blue Hills in Apache County, east-central Arizona. These diminutive scutes, collected by c.L. Camp in the 19...
The Paleobiology of Coelophysis bauri (Cope) from the Upper Triassic (Apachean) Whitaker quarry, New Mexico, with detailed analysis 2009 2463 Here, we investigate the paleobiology of a single population of the Late Triassic dinosaur Coelophysisbauri from the Whitaker quarry at Ghost Ranch, New Mexico. The quarry, discovered by George Whitaker of the American Museum of Natural History in 19...
Permian Footprints and Facies [Table of Contents - Co-editor of this issue] 1995 4366 Cover & Table of Contents
Phytosaur (Archosauria: Parasuchidae) cranial and mandibular material from the Upper Triassic Snyder quarry (Petrified Forest Formation, Chinle Group): 2003 1441 The Upper Triassic Snyder quarry has produced the remains of several pseudopalatine phytosaurs that we refer to Pseudopalatus buceros. This material includes at least four complete skulls (two are fully prepared), two partial skulls, as well as nume...
A phytosaur skull from the Upper Triassic Snyder quarry (Petrified Forest Formation, Chinle Group) of north-central New Mexico 2002 2124 We describe the skull of a subadult pseudopalatine phytosaur from the Late Triassic Snyder quarry, in the Petrified Forest Formation of the Chinle Group, north-central New Mexico. The specimen is complete with minimal distortion. The squamosal bars a...
Pliocene (latest Hemphillian and Blancan) vertebrate fossils from the Mangas Basin, southwestern New Mexico 1997 4713 Two vertebrate faunas of Pliocene age, the Walnut Canyon and Buckhorn local faunas, are described from sediments of the Gila Group in the Mangas basin in northern Grant County, southwestern New Mexico. Stratigraphic sections and lithologic descriptio...
Position of the Triassic–Jurassic boundary and timing of the end-Triassic extinctions on land: Data from the Moenave Formation on the southern Colorado Plateau, USA 2011 845 Strata of the Moenave Formation on and adjacent to the southern Colorado Plateau in Utah–Arizona, U.S.A., represent one of the best known and most stratigraphically continuous, complete and fossiliferous terrestrial sections across the Triassic–Juras...
Postcranial anatomy of Angistorhinus, a Late Triassic phytosaur from West Texas 2002 2632 We describe here an incomplete postcranial skeleton associated with a complete skull and jaws of the phytosaur Angistorhinus grandis Mehl from the Otischalkian (late Carnian) Colorado City Formation of the Chinle Group in Howard County, Texas. The ...
Preliminary description of coelophysoids (Dinosauria:Theropoda) from the Upper Triassic (Revueltian:early-mid Norian) Snyder quarry, north-central New Mexico 2000 1309 The Upper Triassic Snyder quarry is the second-most productive theropod locality in the Chinle Group. Skull and postcranialelements, particularly tibiae, collected from the Snyder quarry during the last three field seasons demonstrate the presence o...
Preliminary report on paleontology of the Abo Formation, McLeod Hills, Sierra County, New Mexico 1995 1723 Six fossil localities in the Abo Formation in the McLeod Hills of Sierra County, New Mexico, produce tetrapod body fossils (jaw of a sphenacodont pelycosaur), fossil plants (Calamites pith cast, Walchia and seed-fern foliar impressions) and tetrapod ...
The rauisuchian archosaur Saurosuchus from the Upper Triassic Chinle Group, southwestern U.S.A. and its biochronological significance 2002 5108 We document the first occurrence of the rauisuchian archosaur Saurosuchus from the Upper Triassic Chinle Group in the southwestern United States. The fossiliferous horizon is low in the Blue Mesa Member of the Petrified Forest Formation in the Blue ...
Re-investigation of enigmatic fish bones known as colobodontid/perleidid toothplates from the Upper Triassic Chinle Group (southwestern U.S.A.) 2006 2862 A representative selection of enigmatic denticulate/dentigerous plates from the Chinle Group previously assigned to Colobodontidae or Perleididae (“Perleidiformes”: Actinopterygii) were reinvestigated and compared to purportedly similar remains of di...
Reinterpretation of the holotype of Malerisaurus langstoni, a diapsid reptile from the Upper Triassic Chinle Group of West Texas 2006 3551 The holotype of Malerisaurus langstoni from the Late Triassic (Otischalkian) Trilophosaurus quarry 2 of West Texas is a chimera. The holotype represents at least 6-7 individuals of four reptilian groups: Trilophosauridae, Rhynchosauridae, Parasuchid...
Review of Upper Triassic Stratigraphy and Biostratigraphy in the Chama basin, Northern New Mexico 2005 2589 Triassic strata in the Chama Basin of Rio Arriba County, New Mexico, pertain to the Upper Triassic Chinle Group (in ascending order, the Zuni Mountains, Shinarump, Salitral, Poleo, Petrified Forest and Rock Point formations). The base of the Chinle ...
Revised Upper Triassic stratigraphy of the Petrified Forest National Park, Arizona, U.S.A. 2002 4476 During the last 40 years, a variety of informal names have been proposed for Upper Triassic stratigraphic units in the Petrified Forest National Park (PFNP) and vicinity. We both simplify and formalize this stratigraphy. All Triassic exposures in th...
Revision of the Archosauromorph Reptile Trilophosaurus, With a Description of the First Skull of Trilophosaurus Jacobsi, From the Upper Triassic Chinle Group, West Texas, Usa 2006 2207 The first abundant, well-preserved fossils of the unusual archosauromorph reptile Trilophosaurus jacobsi Murry are from an Upper Triassic bonebed in the lower-most Trujillo Formation of the Chinle Group in Borden County, Texas. A nearly complete left...
Revision of Redondasuchus (Archosauria: Aetosauria) from the Upper Triassic Redonda Formation, New Mexico, with description of a new species 2006 1390 We describe a new species of aetosaur, Redondasuchus rineharti, based on isolated scutes and an incomplete femur from a single locality in the Upper Triassic Redonda Formation of east-central New Mexico. R. rineharti is distinguished from R. reseri, ...
A revision of the Upper Triassic ornithischian dinosaur Revueltosaurus, with a description of a new species. 2002 3892 Ornithischian dinosaur body fossils are extremely rare in Triassic rocks worldwide, and to date the majority of such fossils consist of isolated teeth. Revueltosaurus is the most common Upper Triassic ornithischian dinosaur and is known from Chinle ...
A Revueltian (Norian) phytosaur from the Sonsela Member of the Petrified Forest Formation (Chinle Group: Upper Triassic), Petrified Forest National Park, Arizona 2003 1893 The Sonsela Member of the Petrified Forest Formation (Upper Triassic) is widely exposed in northeastern Arizona and northwestern New Mexico. Fossil wood is common in the fluvial Sonsela, but the high energy depositional conditions appear to have de...
A revueltosaur-like tooth from the Petrified Forest Formation (Upper Triassic: Revueltian), Zion National Park 2006 1613 We describe an isolated archosauriform tooth from the Upper Triassic Painted Desert Member of the Petrified Forest Formation in Zion National Park in southwestern Utah. This tooth is relatively low (mesiodistally as long as baso-apically tall), bulb...
The rhynchosaur Hyperodapedon from the Upper Triassic of Wyoming and its global biochronological significance 2002 3338 Fragmentary fossils collected by one of us (NH) from the Upper Triassic Popo Agie Formation represent the first occurrence of the rhynchosaur Hyperodapedon in the Chinle Group. The Wyoming record is of Otischalkian (Late Triassic: late Carnian) age...
The Rondan jacket support clamp and jacket transport sled 2000 1034 The RONDAN jacket support clamp and jacket transport sled are inexpensive, relatively easily fabricated tools which have proved invaluable for the field collection of large vertebrate specimens. Although there are some complicating factors, both of ...
Rotten Hill: A Late Triassic Bonebed In The Texas Panhandle, USA 2016 675 The Rotten Hill bonebed is a Late Triassic fossil locality in the Texas Panhandle discovered by Floyd V. Studer in 1926, and collected primarily by WPA-funded excavations during the late 1930s and early 1940s. This locality is in the lower part of th...
Skull of the dicynodont Placerias from the Upper Triassic of Arizona 2002 1858 We describe here a rare, incomplete but articulated skull of the dicynodont Placerias from the Blue Mesa Member of the Petrified Forest Formation in northern Arizona. This specimen comes from near the type locality of P. hesternus Lucas, 1904 in th...
Specimens of Gomphotherium in the New Mexico Museum of Natural History and Science and the species-level taxonomy of Gomphotherium 2000 2358 There are four identifiable specimens of Gomphotherium in the collections of the New Mexico Museum of Natural History and Science in Albuquerque, all collected in New Mexico. The most diagnostic specimen, NMMNH P-28972, consists of a nearly complet...
Stratigraphy and Biostratigraphy of an Upper Cretaceous Outlier Near Roy, Harding County, New Mexico 2001 2518 Upper Cretaceous strata exposed as outliers near Roy in Harding County, New Mexico, are assigned to the Graneros Shale and the overlying Greenhorn Formation. The Greenhorn Formation locally consists of three members (in ascending order): Lincoln, Har...
Stratigraphy and Correlation of Triassic Strata Around the Nacimiento and Jemez Uplifts, Northern New Mexico 1996 3489 Triassic strata exposed along the flanks of the Nacimiento and Jemez uplifts (Sandoval County, northern New Mexico) belong to the Middle Triassic Moenkopi Formation (Anton Chico Member) and the Upper Triassic Chinle Group (Agua Zarca, Salitral, Pol...
Stratigraphy and Paleontology of the Lower Chinle Group (Adamanian: latest Carnian) in the Vicinity of St. Johns, Arizona 2003 2287 Topographically low exposures of Upper Triassic Chinle Group strata near St. Johns, Arizona, overlie the Middle Triassic Moenkopi Formation and can be assigned to four formation-rank units. These are, in ascending order, the Zuni Mountains (= “mottle...
STRATIGRAPHY OF THE LOWER PERMIAN HUECO GROUP IN THE ROBLEDO MOUNTAINS, DONA ANA COUNTY, NEW MEXICO 1998 1598 Most of the Paleozoic strata exposed in the Robledo Mountains, Dona Ana County, New Mexico have long been referred to the Hueco Formation divided into four informal members. We re-visit stratigraphy by elevating Hueco to group status in the Robledo M...
Stratigraphy of the Upper Triassic Chinle Group, Four Corners Region 1997 6850 Upper Triassic strata exposed in the Four Corners region belong to the Chinle Group of late Carnian-Rhaetian age. Chinle Group strata can be divided into eight lithostratigraphic intervals: (1) mottled stratalTemple Mountain Formation-as much as 31...
STRATIGRAPHY, PALEONTOLOGY AND DEPOSITIONAL ENVIRONMENTS OF THE LOWER PERMIAN ROBLEDO MOUNTAINS FORMATION OF THE HUECO GROUP, ROBLEDO MOUNTAINS, NEW MEXICO 1998 1123 Early Permian fossil localities, including numerous tracksites, in the southern Robledo Mountains of Dona Ana County, New Mexico, cover an area of approximately 20 km2 . Lower Permian strata exposed here belong to four formations of the Hueco Group (...
Stratigraphy, taphonomy, and new discoveries from the Upper Jurassic (Morrison Formation: Brushy Basin Member) Peterson quarry, central New Mexico 2000 2330 The Upper Jurassic Peterson quarry, located in Bernalillo County, central New Mexico, is New Mexico's most extensive and productive Jurassic dinosaur locality. The quarry is developed in the upper Brushy Basin Member of the Morrison Formation, approx...
A tale of two sites: A taphonomic comparison of two Late Triassic (Chinle Group) vertebrate fossil localities from New Mexico 2002 1371 New Mexico Museum of Natural History (NMMNH) localities 3379-3381 are located on the western flank of the Lucero uplift in central New Mexico and are approximately 250 Ma old. The site, which is low in the Bluewater Creek Formation of the lower Chi...
Taphonomy of the Lamy Amphibian Quarry: A Late Triassic bonebed in New Mexico, U.S.A. 2010 4047 Located in Santa Fe County, New Mexico, USA, the Lamy amphibian quarry is a Late Triassic (Adamanian) bonebed stratigraphically low in the Garita Creek Formation of the Chinle Group. Well known for its mass accumulation of metoposaurid amphibians, it...
Taphonomy of the Late Triassic Lamy amphibian quarry (Garita Creek Formation: Chinle Group), central New Mexico 2002 4515 The Lamy amphibian quarry, located in central New Mexico in the Upper Triassic Garita Creek Formation of the Chinle Group, is a paucispecific assemblage dominated by the remains of large metoposaurid amphibians assigned to Buettneria perfecta. The qu...
Taphonomy of the Lower Permian Cardillo Quarry, Chama Basin, North-Central New Mexico 2005 1648 The Lower Permian Cardillo quarry is located near Arroyo del Agua, in the Chama Basin in north-central New Mexico. The quarry is stratigraphically high in the El Cobre Canyon Formation of the Cutler Group, which is Wolfcampian in age. During excava...
Taxonomic status of Seismosaurus hallorum, a Late Jurassic sauropod dinosaur from New Mexico 2006 3915 The holotype of the Late Jurassic sauropod dinosaur Seismosaurus hallorum consists of part of the thoracic and caudal vertebrae, most of the sacrum and pelvis, some ribs and chevrons and an incomplete femur. Reexamination of the holotype indicates th...
Taxonomy and biostratigraphy of the Late Triassic archosauromorph Trilophosaurus 2007 1334 Trilophosaurus is an aberrant archosauromorph from the Upper Triassic Chinle Group of the southwestern United States. We review the history of study of Trilophosaurus, revise the diagnosis of the genus and both species of Trilophosaurus, T. buettneri...
Tetrapod biostratigraphy and biochronology across the Triassic- Jurassic boundary in northeastern Arizona 2005 2229 Nonmarine fluvial, eolian and lacustrine strata of the Chinle and Glen Canyon groups in northeastern Arizona and adjacent areas preserve tetrapod body fossils and footprints that are one of the world’s most extensive tetrapod fossil records across t...
The tetrapod fauna of the Upper Triassic lower Chinle Group (Adamanian:latest Carnian), of the Zuni Mountains, west-central New Mexico 1997 1405 Numerous localities in the Bluewater Creek Formation in the Zuni Mountains of westcentral New Mexico produce a tetrapod fauna that includes the metoposaurid amphibian Buettnena sp., indeterminate phytosaurs, the aetosaurs Stagonolepis, Desmatosuchus...
Tetrapod fauna of the Upper Triassic (Revueltian) Owl Rock Formation, Chinle Group, Arizona 2007 1057 The Owl Rock Formation, upper Chinle Group, crops out in the Four Corners area. In the 1980s, Kirby made an extensive collection of vertebrate fossils from the Owl Rock Formation in the Ward Terrace area, northeastern Arizona. We review the Owl Rock...
Tetrapod Footprints from the Middle Triassic (Perovkan—Early Middle Anisian) Moenkopi Formation, West-Central New Mexico 2003 1512 Tetrapod footprints from a locality near Prewitt, Cibola County, New Mexico, are in the lower part of the Anton Chico Member of the Moenkopi Formation. These Perovkan age (early Anisian) footprints represent three tetrapod ichnotaxa: swimming traces,...
A Thin-Shelled Reptile from The Late Triassic of North America and the Origin of the Turtle Shell 2009 509 A new, thin-shelled fossil from the Upper Triassic (Revueltian: Norian) Chinle Group of New Mexico, Chinlechelys tenertesta, is one of the most primitive known unambiguous members of the turtle stem lineage. The thin-shelled nature of the new turtle ...
Tooth enamel microstructure of Revueltosaurus and Krzyzanowskisaurus (Reptilia: Archosauria) from the Upper Triassic Chinle Group, USA: Implications for function, growth, and phylogeny 2013 1556 Tooth enamel microstructure can carry significant phylogenetic, ontogenetic, and functional information within amniotes. Here we provide the first descriptions of the tooth enamel microstructure of two Late Triassic taxa, the crurotarsan Revueltosa...
Topotypes of Typothorax coccinarum, a Late Triassic aetosaur from the American Southwest. 2007 1105 The syntype specimens of the aetosaur Episcoposaurus horridus Cope, 1887, are from the type locality of Typothorax coccinarum Cope, 1875, in the Painted Desert Member of the Petrified Forest Formation, Chinle Group at Cerro Blanco, Rio Arriba County,...
Triassic Dinosaurs in New Mexico 2000 3970 New Mexico is unique among Western states in possessing an extensive and diverse record of Triassic dinosaurs. This record is the world's most complete for understanding Triassic theropod evolution from Adamanian (latest Carnian) through Apachean (...
Triassic strata at Carrizo Arroyo, Lucero uplift, Central New Mexico 2004 1455 Triassic strata exposed at Carrizo Arroyo in the Lucero uplift of central New Mexico are assigned to the Middle Triassic Anton Chico Member ofthe Moenkopi Formation and the Upper Triassic Chinle Group (Zuni Mountains Formation and lower part of the S...
Triassic Stratigraphy Around the Sandia Uplift, Central New Mexico 1995 2392 Triassic strata crop out around the Sandia uplift in the Hagan basin, Placitas and Cedar Crest areas. A uniform Triassic section of nonmarine red siliciclastics as much as 480 m thick is exposed across all three areas. The base of the Triassic sect...
Triassic Stratigraphy in the Lucero Uplift, Cibola, Valencia and Socorro Counties, New Mexico 1994 2626 Triassic strata exposed. in the Lucero uplift of Cibola, Valencia and Socorro Counties are nonmarine red beds of the Moenkopi Formation and Chinle Group. Moenkopi Formation strata disconformably overlie Middle Permian (Guadalupian) limestones and dol...
Triassic Stratigraphy in the Zuni Mountains, West-Central New Mexico 2003 2618 The Triassic System in the Zuni Mountains consists of one Middle Triassic unit, the Moenkopi Formation, the Upper Triassic Chinle Group, and the Upper Triassic-Lower Jurassic(?) Wingate Sandstone. The Chinle Group in the Zuni Mountains consists of si...
Triassic Stratigraphy, Biostratigraphy and Correlation in East-Central New Mexico 2001 4027 Triassic strata in east-central New Mexico are siliciclastic red beds of Middle and Late Triassic age. As much as –500 m thick, the Triassic section is assigned to the Middle Triassic Moenkopi Formation (Anton Chico Member) and overlying Upper Triass...
Triassic vertebrate fossils in Arizona 2005 9900 The Triassic System in Arizona has yielded numerous world-class fossil specimens, including numerous type specimens. The oldest Triassic vertebrates from Arizona are footprints and (largely) temnospondyl bones from the Nonesian (Early Triassic: Spat...
TRIASSIC VERTEBRATE PALEONTOLOGY IN NEW MEXICO 2016 2134 Abstract—The Triassic vertebrate paleontological record of New Mexico includes important assemblages of tetrapod fossils from both the Middle Triassic Moenkopi Formation and the Upper Triassic Chinle Group. The Anton Chico Member of the Moenkopi Form...
Trilophosaurus (Archosauromorpha: Trilophosauridae) Postcrania From The Upper Triassic Blue Mesa Member Of The Petrified Forest Formation (Carnian: Adamanian), Arizona, Usa 2013 1255 Trilophosaurus is a genus of Late Triassic archosauromorph known exclusively from the American Southwest. The defining characteristic of the taxon is its transversely arranged, tricuspid teeth. Here, we document various Trilophosaurus postcrania from...
Trilophosaurus (Archosauromorpha: Trilophosauridai) Postcrania from the Upper Triassic Blue Mesa Member of the Petrified Forest Formation (Carnian: Adamanian), Arizona, USA 2013 1414 Trilophosaurus is a genus of Late Triassic archosauromorph known exclusively from the American Southwest. The defining characteristic of the taxon is its transversely arranged, tricuspid teeth. Here, we document various Trilophosaurus postcrania from...
The type locality of Belodon buceros Cope, 1881, a phytosaur (Archosauria: Parasuchidae) from the Upper Triassic of north-central New Mexico 2002 1633 Here we establish the stratigraphic and geographic provenance of the "Belodon" buceros Cope. The holotype, originally collected by David Baldwin in 1881, is an incomplete phytosaur skull discovered near "Huerfano Camp" in north-central New Mexico. Th...
An Upper Jurassic Theropod Dinosaur from the Section 19 Mine, Grants Uranium District 2003 3159 Known vertebrate fossil occurrences from Jurassic strata in the mines in the Grants uranium district are few. Here, we describe fragmentary teeth, skull, and jaw elements that probably pertain to the theropod dinosaur Allosaurus. These fossils were r...
The Upper Triassic (Norian: Revueltian) Snyder quarry, Chama basin, north-central New Mexico: An Overview: An Overview 2003 1358 Overview of studies within Bulletin 24
Upper Triassic stratigraphy and biostratigraphy, Chama basin, northcentral New Mexico 2003 4211 Triassic strata in the Chama basin of Rio Arriba County, New Mexico, pertain to the Upper Triassic Chinle Group (in ascending order, the Zuni Mountains, Shinarump, Salitral, Poleo, Petrified Forest and Rock oint formations). The local base of the Ch...
Upper Triassic Tetrapods from the Lucero Uplift, Central New Mexico 1999 1716 Six localities in the lower Chinle Group of central New Mexico yield a tetrapod fauna consisting of the diminutive metoposaurid cf. Apachesaurus sp., and indeterminate large metoposaurids (probably Buettneria sp.), the phytosaur Rutiodon sp., indet...
The vertebrate fauna of the Upper Triassic (Norian: Revueltian) Snyder quarry 2003 1787 Since the first scientific excavations, it has been apparent that the Snyder quarry represents a unique vertebrate fossil assemblage. This assemblage includes an apparent xenacanthid shark, semionotid and redfieldiid fish, a metoposaurid amphibian, a...
The Vertebrate Fauna of the Upper Triassic (Revueltian: early-mid Norian) Painted Desert Member (Petrified Forest Formation: Chinle Group) in the Chama Basin, Northern New Mexico 2005 2454 The Upper Triassic Painted Desert Member of the Petrified Forest Formation in north-central New Mexico yields one of the most extensive and significant Revueltian (early-mid Norian) tetrapod faunas known. Particularly significant aspects of this faun...
Vertebrate paleontology of the Robledo Mountains Member of the Hueco Formation, Doña Ana Mountains 1995 2078 Nine localities in the Robledo Mountains Member of the Hueco Formation in the Dona Ana Mountains of southern New Mexico produce nonmarine fossils of plants, vertebrate bone and tetrapod footprints. We describe and illustrate specimens of the followin...