Yuong-Nam Lee

A new nodosaurid ankylosaur (Dinosauria: Ornithischia) from the Paw Paw Formation (Late Albian) of Texas

ABSTRACT Pawpawsaurus campbelli gen. et sp. nov. from the Paw Paw Formation (late Albian), Tarrant County, Texas, appears more primitive than other pre-Campanian nodosaurids, Silvisaurus condrayi and Sauropelta edwardsi. New cranial synapomorphies for the Nodosauridae are prominent W-shaped basioccipital tubera, anteriorly concave and anteroposteriorly flattened quadrate, and transversely continuous and straight posterior margin of the pterygoid aligned with the quadrate shaft. These synapomorphies are closely related to the downward orientation of the nodosaurid head in life. A pair of bony eyelids recovered with the skull are the first discovered for the Nodosauridae. Other Paw Paw Formation nodosaurid remains, including new postcranial elements and a baby nodosaurid, are taxonomically indeterminate.

A review of vertebrate faunas from the Gyeongsang Supergroup (Cretaceous) in South Korea

Abstract The Early Cretaceous is rapidly being recognized as a crucial time in the origin and dispersal of living vertebrate groups. Cretaceous trackways in Korea are among the most abundant in the world and include the smallest sauropod tracks known, plus four avian ichnotaxa, one of which is the earliest record of a bird with webbed feet. Body fossils and egg shells are less well known, however, and have been reported mainly in Korean journals. An increase in the rate of discovery of vertebrate fossils in recent years has resulted in documentation of 38 localities from the entirely fluvio-lacustrine Gyeongsang Supergroup (Hauterivian to Cenomanian) in Korea. Specimens include fish, turtle, crocodilian, pterosaur, and dinosaur bones, and dinosaur eggs in nests, as well as dinosaur, bird, and pterosaur footprints. Scattered bones have been collected in road cuts, quarries, stream beds, and coastal exposures, but localities have yet to be systematically explored and excavated. Nevertheless, very recent finds of articulated fish skeletons and dinosaur egg nests indicate that further exploration may be expected to yield better preserved, more fully associated specimens of these and additional taxa. This would provide further important data for our understanding of this pivotal period in vertebrate evolution.

MANUS-ONLY SAUROPOD TRACKS IN THE UHANGRI FORMATION (UPPER CRETACEOUS), KOREA AND THEIR PALEOBIOLOGICAL IMPLICATIONS

Abstract One hundred and five sauropod tracks were excavated from black shale of the Uhangri Formation (upper Cretaceous), Haenam County, South Chulla Province, Korea. The tracks are true manus prints (not undertracks) and were made by sauropod dinosaurs while swimming.

A New Deinonychosaurian Track from the Lower Cretaceous Hekou Group, Gansu Province, China

Herein we describe deinonychosaurian (Dinosauria: Theropoda) tracks in the Lower Cretaceous Hekou Group at sites I and II of Liujiaxia Dinosaur National Geopark, Gansu Province, China. The site preserves 71 didactyl tracks, the largest concentration of deinonychosaurian tracks in Asia. The tracks pertain to a new dromaeopodid ichnospecies: Dromaeosauripus yongjingensis ichnosp. nov., which is diagnosed by: a digital pad formula of x-1-3-4-x and a mean divarication angle between digits III and IV of 19°, and having the proximal portion of digit II contacting the anterior margin of a large, rounded metatarsophalangeal pad. Six Dromaeosauripus trackways from site II comprise at least two, and possibly three, turning trackways in which the track maker(s) turned without slowing down. None of the Dromaeosauripus trackways are parallel or closely spaced, suggesting that they were made by solitary track makers. Estimates of dromaeopodid track-maker sizes are between 61–300 cm, well within the size range established by body fossils of both dromaeosaurids and troodontids.

The Archosauria from the Woodbine Formation (Cenomanian) in Texas

The archosaur fauna from the Woodbine Formation (Cenomanian), Tarrant County, Texas includes crocodiles, theropod, nodosaurid, and hadrosaurid dinosaurs. A new neosuchian crocodile, Woodbinesuchus byersmauricei new genus and species, appears to be a longirostrine goniopholid. Isolated theropod teeth include morphotypes similar to Richardoestesia. Nodosaurid premaxillary teeth are unique among early nodosaurids in having no marginal cusps. Hadrosaurid remains represent the oldest hadrosaurs east of the Western Interior Seaway.

New material of dsungaripterid pterosaurs (Pterosauria: Pterodactyloidea) from western Mongolia and its palaeoecological implications

New material of dsungaripterid pterosaurs from the Early Cretaceous of Tatal, western Mongolia, allows the diagnoses of Dsungaripteridae and Noripterus to be amended. All pterosaurs found at Tatal belong to Dsungaripteridae (either Dsungaripterus or Noripterus ). The name Phobetor is a junior synonym of Noripterus . The differing shapes of the anterior tips of skulls, differing tooth morphologies and the coexistence of both Dsungaripterus and Noripterus may imply that they occupied distinct ecological niches.

The first ceratopsian dinosaur from South Korea

In 2008, a new basal neoceratopsian was discovered in the Tando beds (Albian) of Tando Basin in South Korea. It represents the first ceratopsian dinosaur in the Korean peninsula and is assigned to Koreaceratops hwaseongensis gen. et sp. nov. Autapomorphies of Koreaceratops include very tall neural spines over five times higher than the associated centra in the distal caudals, and a unique astragalus divided into two fossae by a prominent craniocaudal ridge on the proximal surface. A phylogenetic analysis indicates that Koreaceratops is positioned between Archaeoceratops and all more derived neoceratopsians, and the elongation of caudal neural spines was an important derived character in non-ceratopsid neoceratopsians. The very tall caudal neural spines in Koreaceratops, Montanoceratops, Udanoceratops, Protoceratops, and Bagaceratops appear to be homoplasious, suggesting an independent adaptation, possibly for swimming. Skeletal evidence suggests that obligate quadrupedalism occurred gradually in neoceratopsians progressing from bipedal through facultative quadrupedalism, to complete quadrupedalism in Coronosauria.

ASSIGNMENT OF YAMACERATOPS DORNGOBIENSIS AND ASSOCIATED REDBEDS AT SHINE US KHUDAG (EASTERN GOBI, DORNGOBI PROVINCE, MONGOLIA) TO THE REDESCRIBED JAVKHLANT FORMATION (UPPER CRETACEOUS)

DAVID A. EBERTH, YOSHITSUGU KOBAYASHI, YUONG-NAM LEE, OCTÁVIO MATEUS, FRANÇOIS THERRIEN, DARLA K. ZELENITSKY, and MARK A. NORELL; Royal Tyrrell Museum, Box 7500, Drumheller, Alberta, Canada, david.eberth@gov.ab.ca; Hokkaido University, Hokkaido, Japan; Korean Institute of Geoscience & Mineral Resources, Daejeon, Korea; Museu da Lourinhã & Universidade Nova de Lisboa, Lourinhã, Portugal; Department of Geoscience, University of Calgary, Calgary, Alberta, Canada; Division of Paleontology, American Museum of Natural History, New York City, USA

A New Oviraptorid Dinosaur (Dinosauria: Oviraptorosauria) from the Late Cretaceous of Southern China and Its Paleobiogeographical Implications

The Ganzhou area of Jiangxi Province, southern China is becoming one of the most productive oviraptorosaurian localities in the world. A new oviraptorid dinosaur was unearthed from the uppermost Upper Cretaceous Nanxiong Formation of Ganzhou area. It is characterized by an anterodorsally sloping occiput and quadrate (a feature shared with Citipati), a circular supratemporal fenestra that is much smaller than the lower temporal fenestra, and a dentary in which the dorsal margin above the external mandibular fenestra is strongly concave ventrally. The position of the anteroventral corner of the external naris in relation to the posterodorsal corner of the antorbital fenestra provides new insight into the craniofacial evolution of oviraptorosaurid dinosaurs. A phylogenetic analysis recovers the new taxon as closely related to the Mongolian Citipati. Six oviraptorid dinosaurs from the Nanxiong Formation (Ganzhou and Nanxiong) are distributed within three clades of the family. Each of the three clades from the Nanxiong Formation has close relatives in Inner Mongolia and Mongolia, and in both places each clade may have had a specific diet or occupied a different ecological niche. Oviraptorid dinosaurs were geographically widespread across Asia in the latest Cretaceous and were an important component of terrestrial ecosystems during this time.

THE FIRST CYPRINID FISH AND SMALL MAMMAL FOSSILS FROM THE KOREAN PENINSULA

Although vertebrate paleontology has lagged behind invertebrate paleontology in Korea, an increase in the rate of discovery of Cretaceous vertebrate fossils in recent years resulted in documentation of 38 localities from the fluvio-lacustrine Gyeongsang Supergroup (Hauterivian to Cenomanian) and recovery of fish, turtle, crocodilian, pterosaur, and dinosaur bones, and dinosaur eggs in nests, as well as dinosaur, bird, and pterosaur footprints (Lee et al., 2001). With respect to Tertiary mammals, Korea has generally been regarded as barren even though fossil mammals were reported from two localities in North Korea by Tokunaga (1933), Takai (1939), and Shikama (1943). They reported six perissodactyls and a carnivore from the Osu Formation (Eocene or Oligocene), Pongsan, Hwanghae Province, and cetacean, proboscidean, and rhinoceros specimens from the Phyonryuk Formation (Miocene), Kilju-Myongcheon, North Hamgyeong Province. These specimens are housed at the University of Tokyo Museum. There have been no subsequent published reports of fossil mammals from either North or South Korea.