A review of the Late Jurassic stegosaurs (Dinosauria, Stegosauria) from the People's Republic of China

2006 ◽  
Vol 143 (5) ◽  
pp. 621-634 ◽  
Author(s):  
SUSANNAH C. R. MAIDMENT ◽  
GUANGBIAO WEI
Keyword(s):  
North America ◽  
Late Jurassic ◽  
Taxonomic Revision ◽  
Upper Jurassic ◽  
Supplementary Data ◽  
Asian Origin ◽  
Republic Of China ◽  
Holotype Specimen ◽  
The World ◽  
Cladistic Analyses

Seven genera of stegosaurian dinosaur have been named on the basis of material from the Upper Jurassic of China, and this represents a diversity of stegosaurs unparalleled around the world at this time. However, many of the original specimens used to diagnose and describe these species are currently unavailable, and the original descriptions and figures are often inadequate. The Chinese stegosaurs have proven ‘unstable’ in the few cladistic analyses of Stegosauria that have been carried out, causing a loss of resolution in cladograms. Supplementary data on previously described specimens are presented here along with a taxonomic revision. Only Tuojiangosaurus multispinus, Chungkingosaurus jiangbeiensis and Gigantspinosaurus sichuanensis are considered to be valid taxa, with autapomorphies pertaining to features of the ilio-sacral blocks and dermal armour in all cases. The holotype specimen of ‘Chialingosaurus kuani’ is a juvenile, bearing no diagnostic characters, and ‘Monkonosaurus lawulacus’ is based on fragmentary and undiagnostic material. ‘Changtusaurus’ and ‘Yingshanosaurus’ have never been described or figured and their whereabouts are unknown, so they are regarded as nomina nuda. This taxonomic revision significantly reduces known stegosaurian diversity worldwide, and shows that the Chinese diversity was similar to that of Europe and North America in the Upper Jurassic. Previously, it had been suggested that the diversity of Chinese stegosaurs indicated an Asian origin for the clade, a claim that cannot now be upheld.

scholarly journals Morphological variation in Naomichelys (Testudinata: Solemydidae): insights from a new specimen from the Lower Cretaceous Cloverly Formation of Montana

2015 ◽  
Author(s):  
Daniel Lawver
Keyword(s):  
North America ◽  
Morphological Variation ◽  
Lower Cretaceous ◽  
Cervical Vertebrae ◽  
Shoulder Girdle ◽  
Distinct Species ◽  
Upper Jurassic ◽  
Holotype Specimen ◽  
Surface Ornamentation ◽  
The Right

Background. Solemydidae is an enigmatic clade of stem turtles, which is primarily represented by fragmentary shell material found in Upper Jurassic and Cretaceous deposits of Europe and North America. Specimens are typically identified by a distinct surface ornamentation comprised of tall, narrow tubercles, which are often incompletely preserved due to taphonomic processes. The only currently recognized North American species of Solemydidae, Naomichelys speciosa was erected in 1908 on the basis of a nearly complete entoplastron from the Lower Cretaceous Cloverly Formation of Montana; however, a far more complete specimen from the Lower Cretaceous Antler Formation of Texas (FMNH PR273) was recently referred to this species and has shed light on the morphology of Naomichelys. Here, I describe a partial skeleton (MOR 941) that was discovered in 1995 near the type locality in Montana, which allows for the first look at variation in many of the skeletal elements of the genus. Methods. Morphological variation of Naomichelys was determined by comparison of MOR 941 to the holotype specimen and FMNH PR273 from the literature. Results. MOR 941 is referable to Solemydidae based on a large, diamond shaped entoplastron, which exhibits the distinctive solemydid surface ornamentation and an entoplastral scute, and is referable to Naomichelys because of its near identical morphology to that of the holotype. This specimen consists of the carapace, plastron, four cervical vertebrae, both shoulder girdles, and the right femur. Preserved carapacial elements are the right costals and peripherals in articulation, albeit somewhat crushed, disarticulated left costals, and a single neural. Using peripheral and costal sutures as well as marginal sulci as landmarks, peripherals 1 – 4 are identified, which indicates that the nuchal notch is either reduced or lacking completely. The plastron is well preserved with only portions of the left bridge and xiphiplastra missing and a central plastral fontanel is completely lacking. Cervical vertebrae 5 – 8 are preserved and show varying states of completeness with C7 being the most complete. Cervical 5 preserves a ventral keel on the centrum that is well developed and projects well beyond the central articulations. The shoulder girdle elements are similar to FMNH PR273 but are less well preserved and are not sutured together. The femur is complete and almost identical to FMNH PR273; however, the distal condyles are equally developed. Discussion. The morphological differences between MOR 941 and the Texas material suggest two plausible conclusions. 1) They demonstrate two different ontogenetic stages of development, with MOR 941 representing a skeletally more mature, albeit smaller individual; or 2) there are two distinct species of Naomichelys from the Lower Cretaceous of North America.

scholarly journals Morphological variation in Naomichelys (Testudinata: Solemydidae): insights from a new specimen from the Lower Cretaceous Cloverly Formation of Montana

2015 ◽  
Author(s):  
Daniel Lawver
Keyword(s):  
North America ◽  
Morphological Variation ◽  
Lower Cretaceous ◽  
Cervical Vertebrae ◽  
Shoulder Girdle ◽  
Distinct Species ◽  
Upper Jurassic ◽  
Holotype Specimen ◽  
Surface Ornamentation ◽  
The Right

Background. Solemydidae is an enigmatic clade of stem turtles, which is primarily represented by fragmentary shell material found in Upper Jurassic and Cretaceous deposits of Europe and North America. Specimens are typically identified by a distinct surface ornamentation comprised of tall, narrow tubercles, which are often incompletely preserved due to taphonomic processes. The only currently recognized North American species of Solemydidae, Naomichelys speciosa was erected in 1908 on the basis of a nearly complete entoplastron from the Lower Cretaceous Cloverly Formation of Montana; however, a far more complete specimen from the Lower Cretaceous Antler Formation of Texas (FMNH PR273) was recently referred to this species and has shed light on the morphology of Naomichelys. Here, I describe a partial skeleton (MOR 941) that was discovered in 1995 near the type locality in Montana, which allows for the first look at variation in many of the skeletal elements of the genus. Methods. Morphological variation of Naomichelys was determined by comparison of MOR 941 to the holotype specimen and FMNH PR273 from the literature. Results. MOR 941 is referable to Solemydidae based on a large, diamond shaped entoplastron, which exhibits the distinctive solemydid surface ornamentation and an entoplastral scute, and is referable to Naomichelys because of its near identical morphology to that of the holotype. This specimen consists of the carapace, plastron, four cervical vertebrae, both shoulder girdles, and the right femur. Preserved carapacial elements are the right costals and peripherals in articulation, albeit somewhat crushed, disarticulated left costals, and a single neural. Using peripheral and costal sutures as well as marginal sulci as landmarks, peripherals 1 – 4 are identified, which indicates that the nuchal notch is either reduced or lacking completely. The plastron is well preserved with only portions of the left bridge and xiphiplastra missing and a central plastral fontanel is completely lacking. Cervical vertebrae 5 – 8 are preserved and show varying states of completeness with C7 being the most complete. Cervical 5 preserves a ventral keel on the centrum that is well developed and projects well beyond the central articulations. The shoulder girdle elements are similar to FMNH PR273 but are less well preserved and are not sutured together. The femur is complete and almost identical to FMNH PR273; however, the distal condyles are equally developed. Discussion. The morphological differences between MOR 941 and the Texas material suggest two plausible conclusions. 1) They demonstrate two different ontogenetic stages of development, with MOR 941 representing a skeletally more mature, albeit smaller individual; or 2) there are two distinct species of Naomichelys from the Lower Cretaceous of North America.

scholarly journals An unusually diverse northern biota from the Morrison Formation (Upper Jurassic), Black Hills, Wyoming

2020 ◽  
Vol 7 ◽  
pp. 29-67
Author(s):  
John Foster ◽  
Darrin Pagnac ◽  
ReBecca Hunt-Foster
Keyword(s):  
North America ◽  
Late Jurassic ◽  
Upper Jurassic ◽  
River Channel ◽  
Black Hills ◽  
Morrison Formation ◽  
Vertebrate Fauna ◽  
Type Area ◽  
First Occurrence

The Little Houston Quarry in the Black Hills of Wyoming contains the most diverse vertebrate fauna in the Morrison Formation (Upper Jurassic) north of Como Bluff and the second-most diverse in the entire formation, after Reed’s Quarry 9. The deposit was an occasionally reactivated abandoned river channel, in interbedded green mudstone and laminated green-gray siltstone above a channel sandstone. The dinosaur material is densely distributed and is disarticulated to articulated, with several associated skeletons. The biota contains charophytes, horsetails, a possible seed fern, possible conifers, gastropods, two types of unionoid bivalves, diplostracans (“conchostracans”), a malacostracan, ray-finned fish, lungfish, a frog, salamanders, two types of turtles, rhynchocephalians, a lizard, choristoderes, two types of crocodyliforms, a pterosaur, Allosaurus and several types of small theropods including Tanycolagreus? and probable dromaeosaurids, numerous Camarasaurus and a diplodocine sauropod, a stegosaur, the neornithischian Nanosaurus, and the mammals Docodon, Amblotherium, and a multituberculate. Among these taxa, one of the unionoid bivalves, an atoposaurid crocodyliform, and the species of Amblotherium, which appear to be new and unique to the locality so far. The Docodon material may represent the first occurrence of D. apoxys outside of its type area in Colorado. Additionally, small, unusual theropod tooth types reported here may represent the first Late Jurassic occurrence of cf. Richardoestesia in North America and a possible abelisauroid, respectively.

Introduction

2020 ◽  
pp. 1-16
Keyword(s):  
North America ◽  
Charitable Giving ◽  
Chinese Diaspora ◽  
Republic Of China ◽  
Monetary Value ◽  
The World ◽  
Chinese Overseas ◽  
Native Place ◽  
Close Family ◽  
Selection Of

Charity is a common feature of diaspora communities the world over. Chinese overseas are no exception.1 Wherever they landed, emigrants from China maintained close family, native-place, and social connections with their communities of origin long after their departure from China, entailing obligations to meet the basic requirements of communities back home while supporting one another in times of need abroad. The monetary value of charitable giving on the part of Chinese communities overseas is difficult to quantify, particularly for the nineteenth and early twentieth centuries, and yet the prominence of charity in the life of the Chinese diaspora and the value placed on charitable initiatives by communities themselves are widely recognized in the historical literature. With this volume we add to that body of work a selection of studies on the place of charity among Cantonese settlers in Australasia and North America over the century leading to the founding of the People’s Republic of China in 1949....

scholarly journals The real Bigfoot: a pes from Wyoming, USA is the largest sauropod pes ever reported and the northern-most occurrence of brachiosaurids in the Upper Jurassic Morrison Formation

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5250 ◽  
Author(s):  
Anthony Maltese ◽  
Emanuel Tschopp ◽  
Femke Holwerda ◽  
David Burnham
Keyword(s):  
North America ◽  
Late Jurassic ◽  
Articular Surface ◽  
Upper Jurassic ◽  
Morrison Formation ◽  
The Real ◽  
Large Size ◽  
Distal Shaft ◽  
Distal Articular Surface ◽  
Ventral Process

A set of associated left pedal elements of a sauropod dinosaur from the Upper Jurassic Morrison Formation in Weston County, Wyoming, is described here. Several camarasaurids, a nearly complete small brachiosaur, and a small diplodocid have been found at this locality, but none match the exceptionally large size of the pedal elements. Next to the associated pedal elements, an isolated astragalus, phalanx and ungual were found, which match the large metatarsals in size. The elements cannot be ascribed to diplodocids due to the lack of a ventral process of metatarsal I. Moreover, the morphology of metatarsal V has a broad proximal end, with a long and narrow distal shaft, which differs fromCamarasaurus. The size of the material and a medially beveled distal articular surface of metatarsal IV imply an identification as a brachiosaurid. This is the largest pes ever reported from a sauropod dinosaur and represents the first confirmed pedal brachiosaur elements from the Late Jurassic of North America. Furthermore, this brachiosaur material (the pes and the small nearly complete specimen) is the northernmost occurrence of brachiosaurids in the Morrison Formation.

scholarly journals Evidence for niche partitioning among ground-height browsing sauropods from the Upper Jurassic Morrison Formation of North America

2018 ◽  
Vol 5 ◽  
pp. 95-103 ◽  
Author(s):  
Julia McHugh
Keyword(s):  
Computed Tomography ◽  
North America ◽  
Late Jurassic ◽  
Feeding Strategy ◽  
Niche Partitioning ◽  
Upper Jurassic ◽  
Ct Scans ◽  
Close Relative ◽  
Morrison Formation ◽  
High Count

Two tooth-bearing snout fragments from a diplodocid sauropod from the Brushy Basin Member of the Morrison Formation (Upper Jurassic) excavated from the Mygatt-Moore Quarry in Rabbit Valley, Colora­do are described. The Mygatt-Moore Quarry has produced thousands of vertebrate fossils from the Brushy Basin Member, with the diplodocid Apatosaurus cf. louisae and the tetanuran Allosaurus fragilis dominat­ing the assemblage. Additionally, remains of another diplodocid, Diplodocus sp., have been found near the quarry within Rabbit Valley. Both specimens in this study preserve eight teeth per alveolar position, as observed through broken surfaces at the gross anatomical level and also through computed tomography (CT) scans. This is inconsistent with the genus Diplodocus sp., which has been previously shown to have a maximum of six teeth per alveolus. The presence of eight replacement teeth per alveolus has previously only been reported in the Cretaceous rebbachisaurid Nigersaurus taqueti, which has been interpreted to have occupied a similar ground-height browsing feeding strategy to both Diplodocus and Apatosaurus. This is the first report of this type of high-count replacement teeth in a diplodocid sauropod from the Morrison Formation. The high number of replacement teeth in a close relative to the contemporaneous Diplodocus provides evidence for niche partitioning among the contemporary ground-height browsing diplodocid sauropods of the Late Jurassic Period in North America.

Biodiversity among Festuca (Poaceae) in North America: diagnostic evidence from DELTA and clustering programs, and an INTKEY package for interactive, illustrated identification and information retrieval

1997 ◽  
Vol 75 (9) ◽  
pp. 1527-1555 ◽  
Author(s):  
Susan G. Aiken ◽  
Cheryl L. McJannet ◽  
Laurie L. Consaul ◽  
Michael J. Dallwitz
Keyword(s):  
Information Retrieval ◽  
North America ◽  
File Transfer Protocol ◽  
Status Change ◽  
File Transfer ◽  
Type Specimens ◽  
Annotated List ◽  
The World ◽  
Cladistic Analyses ◽  
Festuca Idahoensis

Biodiversity among taxa of Festuca occurring in North America has been investigated from a revised and illustrated database developed using the DELTA software package. The database includes common names; the place of valid publication of the name; the location of type specimens, when known, and whether we have examined them; synonymy; data on morphology, anatomy, and chromosome number(s); habitat and distribution information; subgeneric classification; taxonomic notes; and more than 200 images. The data are available on the Internet via the World Wide Web (WWW) at http://www.keil.ukans.edu/delta/or by anonymous file transfer protocol (ftp) from ftp.keil.ukans.edu, as natural-language descriptions and as an INTKEY interactive identification and information-retrieval package for MS-Windows. INTKEY and other DELTA programs have been used to assess biodiversity and have supported recognition of several species that have often been placed into synonymy (e.g., Festuca calligera and Festuca earlei), a status change for Festuca idahoensis subsp. roemeri comb.nov., placing Festuca brachyphylla subsp. breviculmis into synonymy with F. brachyphylla subsp. coloradensis, and suggested a taxonomy that is presented in an annotated list. Phenetic and cladistic analyses suggest that the traditional generic limits of Festuca and Lolium should be retained and four subgenera recognized within Festuca, subgg. Festuca, Leucopoa, Schedonorus, and Subulatae, with sects. Subulatae and Obtusae. Key words: DELTA, Festuca, Lolium, Poaceae, biodiversity, WWW, taxonomy.

scholarly journals Evidence for niche partitioning among ground-height browsing sauropods from the Upper Jurassic Morrison Formation of North America

2018 ◽  
Vol 5 ◽  
pp. 95-103 ◽  
Author(s):  
Julia B. McHugh
Keyword(s):  
Computed Tomography ◽  
North America ◽  
Late Jurassic ◽  
Feeding Strategy ◽  
Niche Partitioning ◽  
Upper Jurassic ◽  
Ct Scans ◽  
Close Relative ◽  
Morrison Formation ◽  
High Count

Two tooth-bearing snout fragments from a diplodocid sauropod from the Brushy Basin Member of the Morrison Formation (Upper Jurassic) excavated from the Mygatt-Moore Quarry in Rabbit Valley, Colora­do are described. The Mygatt-Moore Quarry has produced thousands of vertebrate fossils from the Brushy Basin Member, with the diplodocid Apatosaurus cf. louisae and the tetanuran Allosaurus fragilis dominat­ing the assemblage. Additionally, remains of another diplodocid, Diplodocus sp., have been found near the quarry within Rabbit Valley. Both specimens in this study preserve eight teeth per alveolar position, as observed through broken surfaces at the gross anatomical level and also through computed tomography (CT) scans. This is inconsistent with the genus Diplodocus sp., which has been previously shown to have a maximum of six teeth per alveolus. The presence of eight replacement teeth per alveolus has previously only been reported in the Cretaceous rebbachisaurid Nigersaurus taqueti, which has been interpreted to have occupied a similar ground-height browsing feeding strategy to both Diplodocus and Apatosaurus. This is the first report of this type of high-count replacement teeth in a diplodocid sauropod from the Morrison Formation. The high number of replacement teeth in a close relative to the contemporaneous Diplodocus provides evidence for niche partitioning among the contemporary ground-height browsing diplodocid sauropods of the Late Jurassic Period in North America.

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