Therizinosauria are an unusual group of theropod dinosaurs, found mostly in the Cretaceous deposits in Mongolia, China and western USA. The basal forms of this group are represented by incomplete or disarticulated material. Here, we report a nearly complete, articulated skeleton of a new basal therizinosaur from the Early Cretaceous Yixian Formation of Jianchang County, western part of Liaoning Province, which sheds light on our understanding of anatomy of basal therizinosaurs. This new dinosaur shows some typical therizinosaur features, such as neural spines of the anterior caudal vertebrae that possess anterior and posterior alae, a rectangular buttress on the ventrolateral side of the proximal end of metacarpal I, and appressed metatarsal shafts. Our phylogenetic analysis suggests that it is a basal therizinosaur (sister taxon to Therizinosauroidea) because it bears many basal therizinosaur characters in the dentition, pelvis and hind limbs. The new therizinosaur described here has unique tooth and jaw characters such as the offsetting of the tooth row by a shelf and dentary teeth with labially concave and lingually convex dentary teeth, similar to ornithopods and ceratopsians.
A new species of Darwinopterus, D. robustodens sp. nov. is described and named. Based on the new specimen, the diagnostic characters of Darwinopterus are amended and include: rostral dentition composed of well‐spaced, spike‐like teeth; the longest teeth are confined to the anterior half of the tooth row; tooth alveoli have raised margins; nasoantorbital fenestra confluent; inclined quadrate; elongate cervical vertebrae with low neural spine and reduced or absent ribs; long tail of more than 20 caudals partially enclosed by filiform extensions of the pre‐ and postzygapophyses; short metacarpus less than 60 per cent length of humerus, fifth toe with two elongate phalanges and curved second pedal phalanx of the fifth toe with the angle between the proximal and distal segments about 130 degrees. The complete specimen of the new pterosaur D. robustodens sp. nov. provides much more osteological information. The differences in tooth morphologies between Darwinopterus modularis and D. robustodens sp. nov. suggest that they filled different ecological niches. The hard integument‐bearing Coleoptera may have been the main food source of Darwinopterus robustodens.
Recent molecular studies have suggested that the clicking beetle families Elateridae, Eucnemidae, Throscidae, and Cerophytidae evolved in the Jurassic and diversified in the Cretaceous. These studies paid little attention to fossils, using them only as dating tools. The identification of Elateridae fossils is challenging, as external synapomorphies are not known for this family. Elateridae can be identified only as something not belonging to the other related families, all of which have diagnostic synapomorphies. Most subfamilies and tribes of Elateridae do possess definite diagnostic characters, however, making their identification feasible. We checked the 28 Elateridae described from Chinese Mesozoic deposits. Twelve were Elateridae, seven were Eucnemidae, and one was a Throscidae. Three species could be Eucnemidae, but showed aberrant characters. Five species could not be placed and may not belong to Elateroidea at all. On the basis of these results we suggest that all previously described Elateridae fossils should be re-checked. They should be searched for synapomorphies defining Eucnemidae, Throscidae, and Cerophytidae. If such characters are not present, a click beetle type of fossil can be placed in Elateroidae incertae sedis. The Mesozoic Chinese Elateridae fossils all belong to clades that do not exist today, whereas the Mesozoic Eucnemidae subfamilies are extant ones. This may be the source of the disagreement between Elateridae fossil age and datings based on molecular studies. One new combination was made: Desmatus ponomarenkoi (Chang, Kiretjshuk & Ren, 2009) NEW COMBINATION (= Paradesmatus ponomarenkoi Chang, Kirejtshuk & Ren, 2009).
The present paper is devoted to an overview on fossil Coleoptera studied from Inner Mongolia, Daohugou (Middle Jurassic, Jiulongshan Formation) and Liaoning (Upper Jurassic‐Lower Cretaceous, Yixian Formation) deposited in Chinese collections. As a result, species of the tribe Sperchopsini and Hydrophilini from Hydrophilidae, families and subfamilies Silphidae, Syndesinae from Lucanidae, Pleocomidae, Trogidae, Trogissitidae, Pyrochroidae, Diaperinae from Tenebrionidae, and Cerambycidae were first registered in the Mesozoic and some families were defined as new. It was shown that many superfamilies represented in the Recent Fauna were formed within the Middle Jurassic and Lower Cretaceous. The materials examined confirm the hypothesis that Cucujiformian beetles are a younger group than other infraordera of Polyphaga (Staphyliniformia and Elateriformia) and, therefore, they appeared in the fossil record only in the late Mesozoic. It was shown and confirmed that most superfamilies appeared in the fossil records before Cucujoidea. The synonymy of Notocupes Ponomarenko, 1964; Sinocupes Lin, 1976, syn. nov.; Amblomma Tan, Ren et Liu 2005, syn. nov.; Euryomma Tan, Ren et Shih, 2006, syn. nov., non Stein, 1899 and Ovatocupes Tan et Ren, 2006, syn. nov.; synonymy of Tetraphalerus Waterhouse, 1901 and Odontomma Tan, Ren et Ge 2006, syn. nov.; and synonymy of Priacmopsis Ponomarenko, 1966 and Latocupes Tan et Ren, 2006, syn. nov. are proposed. Sinorhombocoleus papposus Tan et Ren, 2009 is transferred from the family Rhombocoleidae to Schizophoridae. Cervicatinius complanus Tan, Ren et Shih, 2007 and Forticatinius elegans Tan, Ren et Shih, 2007 are transferred from the family Catiniidae (suborder Archostemata) to superfamily Cleroidea (suborder Polyphaga: first among the family Peltidae and second as a closely related group to the latter family). The family Parandrexidae is transferred from the superfamily Cucujoidea to Cleroidea. The ecological circumstances of the past ecosystems and hypotheses of historical development of the order Coleoptera are discussed. The age of faunas examined is considered. The list of the taxa described from Daohugou and Liaoning is compiled.
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.
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