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Tyrannosaurid theropods topped the terrestrial food chain in North America and Asia during the latest Cretaceous. Most tyrannosaurids, exemplified by Tyrannosaurus rex, had deep snouts, thick teeth, and large jaw muscles that could generate high bite forces. They coexisted in Asia with a morphologically divergent group of long-snouted relatives, called alioramins. Qianzhousaurus sinensis, from the Maastrichtian of Ganzhou, China, is the largest alioramin yet discovered, but has only been briefly described. Here we present a detailed osteological description of the holotype cranium and mandible of Qianzhousaurus. We identify several new autapomorphic features of the genus, and new synapomorphies that unite alioramins (Qianzhousaurus, Alioramus altai, Alioramus remotus) as a clade, including a laterally projecting rugosity on the jugal. We clarify that the elongate skull of alioramins involves lengthening of the anterior palate but not the premaxilla, and is reflected by lengthening of the posterior bones of the lower jaw, even though the posterior cranium (orbit and lateral temporal fenestra) are proportionally similar to deep-skulled tyrannosaurids. We show that much of the variation among the alioramin species is consistent with growth trends in other tyrannosaurids, and that A. altai, A. remotus, and Qianzhousaurus represent different ontogenetic stages of progressive maturity, across which the signature nasal rugosites of alioramins became less prominent. We predict that the holotype skull of Qianzhousaurus represents the adult level of maturity for alioramins, and propose that the skull morphology of Qianzhousaurus indicates a much weaker bite than deep-skulled tyrannosaurids, suggestive of differences in prey choice and feeding style.

Oviraptorosaurs are bird-like theropod dinosaurs that thrived in the final pre-extinction ecosystems during the latest Cretaceous, and the beaked, toothless skulls of derived species are regarded as some of the most peculiar among dinosaurs. Their aberrant morphologies are hypothesized to have been caused by rapid evolution triggered by an ecological/biological driver, but little is known about how their skull shapes and functional abilities diversified. Here, we use quantitative techniques to study oviraptorosaur skull form and mandibular function. We demonstrate that the snout is particularly variable, that mandibular and upper/lower beak form are significantly correlated with phylogeny, and that there is a strong and significant correlation between mandibular function and mandible/lower beak shape, suggesting a form-function association. The form-function relationship and phylogenetic signals, along with a moderate allometric signal in lower beak form, indicate that similar mechanisms governed beak shape in oviraptorosaurs and extant birds. The two derived oviraptorosaur clades, oviraptorids and caenagnathids, are significantly separated in morphospace and functional space, indicating that they partitioned niches. Oviraptorids coexisting in the same ecosystem are also widely spread in morphological and functional space, suggesting that they finely partitioned feeding niches, whereas caenagnathids exhibit extreme disparity in beak size. The diversity of skull form and function was likely key to the diversification and evolutionary success of oviraptorosaurs in the latest Cretaceous. [Abstract copyright: © 2019 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2019 European Society For Evolutionary Biology.]

The character list and data matrix for phylogenetic analysis

Alvarezsaurid diversity has been markedly increased by recent discoveries from China. However, the number of alvarezsaurid specimens in the Nemegt Formation of Mongolia remained low since the initial report on Mononykus olecranus in 1993. Here we report three new alvarezsaurid specimens from this formation, which were associated with each other and also with multiple oviraptorid skeletons in a small multi-species assemblage. Two of the alvarezsaurid specimens represent a new taxon, Nemegtonykus citus gen. et sp. nov., which is mainly distinguished from other alvarezsaurids by the first sacral vertebra with a subtrapezoidal lamina, the second sacral centrum which is directly co-ossified with ilium, the posterodorsally oriented postacetabular process of ilium, and partial co-ossification between metatarsals II and IV. The other specimen is very similar to M. olecranus in morphology and referred to cf. Mononykus sp. Our phylogenetic analysis recovered Nemegtonykus as a parvicursorine forming a polytomy with several other taxa from the Gobi Desert. The presence of three alvarezsaurid individuals in the same locality indicates that the abundance of alvarezsaurids have been greatly underestimated in the Nemegt dinosaur faunas.

From an initial isolated position as the oldest evolutionary prototype of a bird, Archaeopteryx has, as a result of recent fossil discoveries, become embedded in a rich phylogenetic context of both more and less crownward stem-group birds, prompting debate over whether Archaeopteryx is simply a convergently bird-like non-avialan theropod. Here we show, using the first synchrotron microtomographic examination of this genus, that the eighth or Daiting specimen of Archaeopteryx possesses a character suite that robustly constrains it as a basal avialan (primitive bird). The specimen, which comes from the Mörnsheim Formation and is thus younger than the other specimens from the underlying Solnhofen Formation, is distinctive enough to merit designation as a new species, Archaeopteryx albersdoerferi sp. nov., but is recovered in close phylogenetic proximity to Archaeopteryx lithographica. Skeletal innovations of the Daiting specimen, such as fusion and pneumatization of the cranial bones, well vascularized pectoral girdle and wing elements, and a reinforced configuration of carpals and metacarpals, suggest that it may have had more characters seen in flying birds than the older Archaeopteryx lithographica. These innovations appear to be convergent on those of more crownward avialans, suggesting that Bavarian archaeopterygids independently acquired increasingly bird-like traits over time. Such mosaic evolution and iterative exploration of adaptive space may be typical for major functional transitions like the origin of flight.

Four heteropod lizard trackways discovered in the Hasandong Formation (Aptian-early Albian), South Korea assigned to Sauripes hadongensis, n. ichnogen., n. ichnosp., which represents the oldest lizard tracks in the world. Most tracks are pes tracks (N = 25) that are very small, average 22.29 mm long and 12.46 mm wide. The pes tracks show “typical” lizard morphology as having curved digit imprints that progressively increase in length from digits I to IV, a smaller digit V that is separated from the other digits by a large interdigital angle. The manus track is 19.18 mm long and 19.23 mm wide, and shows a different morphology from the pes. The predominant pes tracks, the long stride length of pes, narrow trackway width, digitigrade manus and pes prints, and anteriorly oriented long axis of the fourth pedal digit indicate that these trackways were made by lizards running bipedally, suggesting that bipedality was possible early in lizard evolution.

Table S1: Mid- to Upper Cretaceous oviraptorosaur egg and clutch specimens examined in this study; Table S2: Results of regression analyses for clutch volume (mm3, in logarithmic scale) against adult body mass (kg, in logarithmic scale) in living crocodylian and precocial bird species (n = 180) in order to predict adult body mass for the elongatoolithid specimens; Table S3: Outer and inner clutch diameters of various oviraptorosaur egg taxa; Table S4: Eggshell thickness of various oviraptorosaur egg taxa; Table S5: Eggshell porosity and predicted nest type in various oviraptorosaur egg taxa; Figure S1. Comparisons of egg shape in oviraptorosaurs.

A new oviraptorid dinosaur from the Late Cretaceous of Ganzhou, bringing oviraptrotid diversity of this region to seven taxa, is described. It is characterized by a distinct cassowary-like crest on the skull, no pleurocoels on the centra from the second through fourth cervical vertebrae, a neck twice as long as the dorsal vertebral column and slightly longer than the forelimb (including the manus). Phylogenetic analysis recovers the new oviraptorid taxon, Corythoraptor jacobsi, as closely related to Huanansaurus from Ganzhou. Osteochronology suggests that the type specimen of Corythoraptor had not reached stationary growth stage but died while decreasing growth rates. The histology implies that it would correspond to an immature individual approximately eight years old. We hypothesize, based on the inner structure compared to that in modern cassowaries, that the prominent casque of Corythoraptor was a multifunction-structure utilized in display, communication and probably expression of the fitness during mating seasons.

A new troodontid dinosaur, Daliansaurus liaoningensis gen. et sp. nov., is erected based on a nearly complete specimen from the Lower Cretaceous Yixian Formation of Beipiao City, Liaoning Province, China. This well preserved skeleton provides important new details of the anatomy for Liaoning troodontids, and gives new insight into their phylogenetic relationships and evolution.Daliansaurus is distinguished from other troodontids by an enlarged ungual on pedal digit IV, which is approximately the same size as the sickle-shaped second ungual, and is differentiated from other Liaoning troodontids by a number of characters of the skull, manus, pelvis, and hindlimb. A phylogenetic analysis recovers Daliansaurus within a subclade of Liaoning troodontids that alsoincludes Sinovenator, Sinusonasus, and Mei. We erect a name for this group—Sinovenatorinae—and argue that it reflects a localized radiation of small-bodied troodontids in the Early Cretaceous of eastern Asia, similar to previously recognized radiations of Liaoning dromaeosaurids and avialans. Asmore Liaoning theropods are discovered, it is becoming apparent that small, feathered paravians were particularly diverse during the Early Cretaceous, and future work is needed to clarify how this diversity arose, which species coexisted, and how these numerous species partitioned niches.

The abundance of dinosaur eggs in Upper Cretaceous strata of Henan Province, China led to the collection and export of countless such fossils. One of these specimens, recently repatriated to China, is a partial clutch of large dinosaur eggs (Macroelongatoolithus) with a closely associated small theropod skeleton. Here we identify the specimen as an embryo and eggs of a new, large caenagnathid oviraptorosaur, Beibeilong sinensis. This specimen is the first known association between skeletal remains and eggs of caenagnathids. Caenagnathids and oviraptorids share similarities in their eggs and clutches, although the eggs of Beibeilong are significantly larger than those of oviraptorids and indicate an adult body size comparable to a gigantic caenagnathid. An abundance of Macroelongatoolithus eggs reported from Asia and North America contrasts with the dearth of giant caenagnathid skeletal remains. Regardless, the large caenagnathid-Macroelongatoolithus association revealed here suggests these dinosaurs were relatively common during the early Late Cretaceous., The fossil dinosaur embryo ‘Baby Louie' and associated clutch of eggs were first discovered in the early 1990s, but were not formally described. Here, the authors identify the specimen as an embryo and eggs of the new large caenagnathid oviraptorosaur, Beibeilong sinensis, from the Late Cretaceous of China.

Post-natal parental care seems to have evolved numerous times in vertebrates. Among extant amniotes, it is present in crocodilians, birds, and mammals. However, evidence of this behavior is extremely rare in the fossil record and is only reported for two types of dinosaurs, and a varanopid ‘pelycosaur’. Here we report new evidence for post-natal parental care in Philydrosaurus, a choristodere, from the Yixian Formation of western Liaoning Province, China. We review the fossil record of reproduction in choristoderes, and this represents the oldest record of post-natal parental care in diapsids to our knowledge.

Four carcharodontosaurid teeth from the Cretaceous deposits of Ruyang County, Henan Province of central China are described in detail. The discovery of these large teeth indicates that some of the ...

Funiusaurus luanchuanensis gen. et sp. nov. was described on the basis of an incomplete skull from the Upper Cretaceous Qiupa Formation of the Tantou Basin in Luanchuan County, Henan Province. It is the second representative of lizards known from Luanchuan and adds a new member to the Luanchuan Fauna. F. luanchuanensis is a small-sized lizard and systematically assigned to the Polyglyphanodontidae of the Teiioidea because of the presence of a caniniform tooth and an elongate posterior process of the postorbital. It is distinctive in that the heterodont dentition bears 19 teeth in both the upper and lower jaws, the 3rd maxillary tooth is large and caniniform, the post-caniniform teeth in maxilla and those posterior to the 3rd dentary tooth are chisel-like in lateral view, the prefrontal possesses a fossa on its lateral surface, the postorbital with an extremely elongate posterior process and the well-developed retroarticular process has a deep fossa on its dorsal surface. In phylogeny, our analysis suggests a close relationship of Funiusaurus to the large-sized Tianyusaurus from the same basin within the Tuberocephalosaurinae. The discovery of Funiusaurus is significant in confirming the status of the Tuberocephalosaurinae, which includes a group of the Asian members of the Polyglyphanodontidae only.

A new partial specimen of Zhenyuanopterus from the Lower Cretaceous Yixian Formation of Beipiao city, Liaoning Province is described. This specimen is slightly larger than half the size of the holotype. Although it is not complete, it provides new information on Zhenyuanopterus both in taxonomy and ontogeny: the total number of the caudal vertebrae is 15; the forelimb is more robust than the hindlimb; the growth rate of the humerus and femur is constant, and their ratio is about 1. Compared with the holotype, the scapula and coracoid grow faster than the humerus and the femur. The scapula and coracoid may slow their growth rate after a certain ontogenetic stage. The pectoral girdle, robust forelimb and weak hindlimb of the new material (XHPM1088) together with data from the holotype of Zhenyuanopterus indicate that this taxon spent less time on land than in the sky or other ecological niches such as forests and cliffs.

Junchang Lü, Rongjun Chen, Stephen L. Brusatte, Yangxiao Zhu, Caizhi Shen (2016): A Late Cretaceous diversification of Asian oviraptorid dinosaurs: evidence from a new species. Scientific Reports 6 (35780): 1-12, DOI: 10.1038/srep35780

Tongtianlong limosus gen. et sp. nov. (Figs 2, 3 and 4) Etymology. Tongtian, Chinese Pinyin, refers to Tongtianyan of Ganzhou, the first grotto south of the Yangtze River. Tongtian also means the road to heaven, a fitting epitaph for a deceased dinosaur preserved with outstretched arms. Long, Chinese Pinyin for dragon. Limosus, Latin for muddy, refers to the holotype specimen being found in an unusual posture in a mudstone (Fig.5). Holotype. A nearly complete, three-dimensionally preserved skeleton with skull and lower jaws (DYM-2013-8). The specimen is accessioned at the Dongyang Museum, Dongyang City, Zhejiang Province. Type locality and horizon. The building site of the No. 3 high school of Ganxian (GPS coordinates are provided on request from the first author); Nanxiong Formation (Maastrichtian, Upper Cretaceous)35. Diagnosis. Oviraptorid dinosaur with the following unique combination of characters, with autapomorphies among all oviraptorosaurs indicated with an asterisk and autapomorphies among oviraptorids indicated with a double asterisk (these latter features are present in some caenagnathids): dome-like skull roof with highest point located above the posterodorsal corner of the orbit*; anterior margin of the premaxilla highly convex in lateral view*; distinct process at the middle of the anterior margin of the parietal on the skull roof*; plate-like lacrimal shaft that is anteroposteriorly long in lateral view, with a flat lateral surface*; foramen magnum smaller than the occipital condyle**; absence of symphyseal ventral process of the dentary**; absence of distinct lateral xiphoid process of the sternum posterior to the costal margin**. Tongtianlong differs from other Ganzhou oviraptorids with preserved skull material (Banji, Huanansaurus) in that the anteroventral corner of the external naris is far above a horizontal line tangent with the posterodorsal corner of the antorbital fenestra, an unusual feature otherwise only seen in Nemegtomaia 36 – 38 and Rinchenia (Barsbold 39) (= Oviraptor mongoliensis 1, 40). Tongtianlong also differs from other Ganzhou oviraptorids in numerous ways that are encapsulated in the character scores in our phylogenetic analysis. Tongtianlong differs from Banji 26 in possessing a postorbital process of the jugal that is posterodorsally inclined relative to the ventral ramus (not perpendicular), lacking a downturned symphyseal portion of the dentary (see also Supplementary Information Fig. S1a), lacking a prominent process on the posteroventral surface of the dentary symphysis, and possessing a more anteroposteriorly elongate external mandibular fenestra. Tongtianlong is distinguished from Ganzhousaurus 27 in lacking a downturned symphyseal portion of the dentary, possessing a more anteroposteriorly elongate external mandibular fenestra, having a dentary that contributes to the ventral border of the external mandibular fenestra (not excluded from the border by the anterior extension of the angular), lacking a depression on the lateral surface of the dentary immediately anterior to the external mandibular fenestra, and possessing a metatarsal III that is anteroposteriorly flattened with a concave posterior surface (not ovoid or subtriangular in cross section). Tongtianlong is different from Jiangxisaurus 28 in lacking a downturned symphyseal portion of the dentary. Furthermore, the ratio of radius length to humerus length (78%) and the height-to-length ratio of the lower jaw (34%) are greater than those of Jiangxisaurus (70% and 20%, respectively). Tongtianlong differs from Nankangia 9 in lacking a prominent process on the posteroventral surface of the dentary symphysis, lacking a deep fossa on the lateral surface of the dentary, having a dentary that contributes to the dorsal border of the external mandibular fenestra (not excluded from the border by the anterior extension of the surangular), and lacking a depression on the lateral surface of the dentary immediately anterior to the external mandibular fenestra. Tongtianlong differs from Huanansaurus 29 in skull morphology and forelimb proportions. There is a crest in Huanansaurus but not in Tongtianlong. The dorsal margin of the lower jaw, from the anterior tip to the coronoid eminence, is smoothly convex in Tongtianlong, whilst it is wave-like in Huanansaurus. The antorbital fenestra is sub-oval in Tongtianlong, but triangular in Huanansaurus. The ratio of radius length to humerus length in Tongtianlong (0.78) is much smaller than that of Huanansaurus (0.97). The anteroventral corner of the external naris is slightly below the horizontal line projected through the posterodorsal corner of the antorbital fenestra in Huanansaurus, whilst it is far above this line in Tongtianlong (Fig.6). Description The specimen is very well preserved in three dimensions, with the bones in natural articulation (Figs2 and 3 a; see also Supplementary Information Table S1). The limbs are splayed out sideways relative to the trunk, and the neck is curved upwards, such that the head is elevated relative to the remainder of the body. Because the specimen was collected by a farmer and construction workers, and it was not mapped in situ while being excavated, it is difficult to interpret what biological and/or taphonomic processes caused this strange posture. Judging by the fine state of preservation, the specimen probably was originally complete or nearly complete. However, some portions of the skeleton are missing, such as the distal regions of the arms, the right pelvic girdle and hind leg, and parts of the tail. This is because the specimen was collected by workers at an active construction site. The specimen was exposed after workmen blasted away some of the surrounding rocks with TNT; a drill hole where TNT was placed can be seen near the pelvic girdle. The skull is almost completely preserved. It is missing only small portions of the anterior end of the premaxilla and nasals, and a small part of the right lower jaw. The most salient feature of the skull is that the cranial roof is dome-like, with its highest point above the posterodorsal corner of the orbit. Many other oviraptorosaurs possess cranial ornaments, which in some cases are elaborate and highly pneumatic (Fig.4). However, in other taxa these crests are usually thinner (such as in Nemegtomaia 36 – 38, it is 6 mm) than the dome-like condition in Tongtianlong. Furthermore, in other taxa these crests are peaked further anteriorly relative to Tongtianlong, either at the anterior end of the snout above the external naris and antorbital fenestra (as in Banji, Citipati, Oviraptor, and Nemegtomaia), or at approximately the midpoint of the cranium above the orbit (as in Rinchenia, Huanansaurus, and caenagnathids like Anzu 41) (Fig.6). Therefore, the posteriorly-peaked dome-like crest of Tongtianlong is autapomorphic among oviraptorosaurs, and a novel type of cranial ornamentation in this highly variable clade. The fine three-dimensional preservation of the specimen ensures that the shape of the dome-like crest is not an artefact of crushing or deformation. There are five main openings in the cranium, as is standard for oviraptorosaurs and other dinosaurs. Anteriorly a large, oval-shaped external naris is positioned above a slightly smaller, triangular antorbital fenestra (Fig.4). The anteroventral corner of the naris is located far above the level of the posterodorsal corner of the antorbital fenestra, which is also the case in Nemegtomaia and Rinchenia, but differs from the condition in most other oviraptorosaurs, in which the naris extends further ventrally so that it reaches past the posterodorsal corner of the antorbital fenestra (Fig.6). The orbit is large and nearly circular, as is typical for oviraptorosaurs. The lateral temporal fenestra is the largest opening in the skull. It is rectangular, with a long axis that extends slightly anteroventrally, which differs from the more circular or square fenestrae of many other oviraptorosaurs. The supratemporal fenestra is positioned above the lateral temporal fenestra and is partially visible in lateral view. It is much smaller than the orbit and lateral temporal fenestra. The premaxilla is toothless like in all derived oviraptorosaurs. The left and right premaxillae appear to be unfused to each other, based on open sutures in the region of the broken dorsal surfaces of both bones, but the premaxilla and maxilla are fused together without a clear sutural trace. The anterior margin of the premaxilla is highly convex, which is an autapomorphy of Tongtianlong. Most other oviraptorosaurs have a straight anterior premaxilla (e.g., Citipati 42, Khaan 42), and this is also the case in the Ganzhou oviraptorid Huanasaurus 29. Yulong and the Ganzhou oviraptorid Banji have a slightly rounded anterior margin of the premaxilla in lateral view, but it is not nearly as convex as in Tongtianlong. The premaxilla is divided into two branches, both of which extend posterodorsally. The upper one forms the anterodorsal margin of the external naris, whereas the much wider lower one forms most of the anterodorsal margin of the antorbital fenestra, thus separating the naris from the antorbital fenestra and completely excluding the maxilla from the narial border. The posterior end of this branch overlaps the lateral surface of the lacrimal. The divergence of the two branches defines the shape of the external naris. Anteroventral to the naris, a deeply concave fossa extends on the lateral surface of the premaxilla, as in Huanasaurus 29, Yulong 10, and Nemegtomaia 37, 38, but unlike the slightly concave surface in Citipati 6. The maxilla is very small and exposed only as a tiny sliver of bone in lateral view. It forms the ventral margin of the antorbital opening and lacks teeth, but has a small triangular ‘tooth-like’ process on its ventral surface. The lacrimal is divided into three branches: a short anterior process that is covered by the premaxilla, a bulbous posterior process that extends dorsally to define the anterodorsal corner of the orbit, and a large ventral shaft. The shape of the shaft is unique: whereas in other oviraptorosaurs the lacrimal shaft is gracile (thin anteroposteriorly) and has at least a partially convex lateral surface (Fig.6), in Tongtianlong it is robust (thick anteroposteriorly) with a flat lateral surface (Fig.4). In effect, the lacrimal shaft of Tongtianlong is plate-like, which is considered an autapomorphy of the taxon. In the region where the three processes meet, the lateral surface of the lacrimal is penetrated by a large opening (called the nasopharyngeal canal by Balanoff and Norell 43) that leads into an internal recess, which is further subdivided internally. Anteroventral to this pneumatic opening is an ovoid fossa on the lateral surface of the lacrimal, which is probably also pneumatic in origin, and which may also invade the bone internally, although poor preservation makes this difficult to confirm. Complex pneumaticity in this region is common in oviraptorosaurs 6, 43). However, the pneumatic openings in Tongtianlong are much larger and more elaborate than the corresponding pneumaticity in the two Ganzhou oviraptorids with well-preserved cranial material, Huanansaurus 29 and Banji 26. The postorbital is triradiate, with short anterior and posterior processes and a very long ventral process that projects anteroventrally, terminating at the floor of the orbit. The slender and elongate jugal is divided into three branches. The rod-like anterior process contacts the lacrimal and maxilla. The short ascending process extends posterodorsally to make up approximately half of the postorbital bar separating the orbit and lateral temporal fenestra. The posterior process contacts the quadratojugal underneath the lateral temporal fenestra. Here, the jugal overlaps the quadratojugal laterally, and the two bones are sutured but not fused. The quadratojugal is tightly appressed to the lateral surface of the quadrate, and it does not appear that the two bones could move relative to each other. There is, however, a small fenestra between the small dorsal process of the quadratojugal and the lateral margin of the quadrate. The dorsal part of quadrate is bent backwards, and there is an opening on the anterior surface of the quadrate which indicates that the bone is pneumatized. On the skull roof, the dorsal surface of the posterior portion of the nasal is smoothly convex. The left and right nasals are fused, without any sign of a suture between them. The lateral surface of the nasal is strongly concave, and although the surface is not well preserved, visible regions of original bone texture indicate extreme pneumaticity in this region, as is standard for derived oviraptorosaurs. The nasal-frontal suture is V-shaped in dorsal view. The frontals are short anteroposteriorly, and the left and right elements are not fused on the midline. The two parietals are fused to each other, but not to the frontals and there is no parietal crest (see also Supplementary Information, Fig. S1b). The frontal-parietal suture is mostly straight, but there is a distinct process extending forwards from the middle of the anterior margin of the parietal (Fig. 3 d, pp). This process is wedged between the frontals. It is considered an autapomorphy of Tongtianlong, as it is absent in other oviraptorosaurs. Portions of the braincase are visible in lateral and posterior view. The supraoccipital is triangular, which a concave posterior surface. The exoccipital-opisthotic forms the dorsal margin of the foramen magnum, thus separating the supraoccipital from the foramen margin. The exoccipital tapers as it extends lateroventrally. The occipital condyle is larger than the foramen magnum, a condition that is seen in some caenagnathids (e.g., Anzu 41), but differs from the proportionally smaller occipital condyles of other oviraptorids. The occipital condyle is located posterior to the articular condyles of the quadrate. The mandible is nearly complete. In lateral view, the ventral margin of the lower jaw is straight. The anterior end of the dentary is not as strongly downturned as in other derived oviraptorids. There is no depressed fossa on the lateral surface of the dentary immediately anterior to the external mandibular fenestra, and there are no articular grooves for the dentary on the ventrolateral edge of the angular and the dorsal surface of the surangular. The dentary contributes widely to the dorsal and ventral margins of the external mandibular fenestra, which is more anteroposteriorly elongated than the circular fenestrae of many other oviraptorids. The posterior part of the surangular is strongly concave laterally, and is pierced by a small opening. Postcranially, the neck is comprised of 11 cervical vertebrae. The first nine of these are preserved in natural articulation, with their dorsal surfaces exposed. In dorsal view the anterior-middle cervicals are roughly square shaped, as defined by lines drawn between the posterior margins of the postzygapophyses, the anterior margins of the prezygapophyses, and the lateral edge of the vertebra (Fig.3 e). They become more rectangular in shape, longer than wide, more posteriorly in the neck. The neural spines are very small, as they are reduced to tiny peg-like projections at the center of the neural arches. The epipophyses are well developed in the second, third and fourth cervical vertebrae, but they become smaller in the middle cervicals and then disappear posterior to the sixth vertebra. There is a pneumatic opening (=pleurocoel) visible on the slightly exposed lateral centrum surface of the second cervical, but the lateral surfaces of the remaining cervicals are covered by matrix. The isolated posterior cervical vertebra, which is not in close articulation with the rest of the neck and therefore more widely exposed than the others, has a concave anterior articular surface of the centrum and a slightly convex posterior articular surface. The dorsal vertebrae were heavily damaged during collection, so few details of their morphology can be observed. The neural spines of the posterior dorsals are tall and slightly expanded anteroposteriorly. Some dorsal ribs are present on both sides of the specimen, none of which exhibit any pneumatic openings on their proximal ends. The sacrum is not well preserved, but the anterior neural spines are clearly unfused to each other and were closely appressed to the medial surface of the ilium in dorsal view. There appears to be a pneumatic foramen (=pleurocoel) on the final sacral vertebra, and the lateral ends of the fused transverse processes and sacral ribs are strongly expanded anteroposteriorly, with rounded dorsal surfaces. Part of the distal tail is missing, but there are at least 19 caudal vertebrae. The caudals are rectangular in dorsal view, with elongate transverse processes that extend laterally and slightly posteriorly. One laterally exposed anterior caudal has a small opening that appears to be pneumatic in nature. The haemal arches are very long. Portions of the shoulder girdles and proximal forearms are present on both sides of the specimen. The scapula is slender and curved medially. Its proximal end is expanded but not fused to the coracoid, the two bones forming an angle of approximately 130 degrees when in articulation. The coracoid is quadrangular in shape and has a large distally tapering posteroventral process, which extends slightly past the glenoid and is rounded at its end. The lateral surface of the coracoid is convex, the distinct biceps tubercle is located anterior to the glenoid, and the small and elongated coracoid foramen is positioned between the dorsal margin of the bone and the biceps tubercle. The medial surface of the coracoid is deeply concave and the coracoid foramen is expressed as a much larger, more circular opening than on the lateral surface. The thin sternum is a single element consisting of fused left and right components. It lacks a lateral xiphoid process and there is no groove for the coracoids along its anterior margin. The furcula is a broadly U-shaped, with a short ventral process on the midline and flattened distal ends (Fig.3 b). The humerus has a long deltopectoral crest, which extends distally for nearly half the length of the shaft (Fig.3 c). The shaft is slightly twisted as in Heyuannia 22 and Nankangia 9. Part of the radius is preserved on the left side, but the ulnae and more distal forelimb elements are missing. Very few details of the pelvic girdle are apparent, due to damage that occurred during collecting. Parts of the ilium and pubis are present but little can be said of their morphology, although the preserved portions indicate that the pelvis is mesopubic and the distal ends of the left and right pubes are not fused together. The ischia are better preserved on the left side. The posterior margin of the shaft is deeply concave, the distal margin of the obturator process is straight, and the lateral surface of the bone is concave. The tibia is longer than the femur. It has a straight shaft, a well-developed cnemial crest, and an expanded distal end with a concave posterior surface. The astragalus is tightly appressed to the

Recent discoveries of new oviraptorosaurs revealed their high diversity from the Cretaceous Period in Asia and North America. Particularly, at the family level, oviraptorids are among the most diverse theropod dinosaurs in the Late Cretaceous of Mongolia and China. A new oviraptorid dinosaur Gobiraptor minutus gen. et sp. nov. from the Upper Cretaceous Nemegt Formation is described here based on a single holotype specimen that includes incomplete cranial and postcranial elements. The most prominent characters of Gobiraptor are its thickened rostrodorsal end of the mandibular symphysis and a rudimentary lingual shelf on each side of the dentary. Each lingual shelf is lined with small occlusal foramina and demarcated by a weakly developed lingual ridge. This mandibular morphology of Gobiraptor is unique among oviraptorids and likely to be linked to a specialized diet that probably included hard materials, such as seeds or bivalves. The osteohistology of the femur of the holotype specimen indicates that the individual was fairly young at the time of its death. Phylogenetic analysis recovers Gobiraptor as a derived oviraptorid close to three taxa from the Ganzhou region in southern China, but rather distantly related to other Nemegt oviraptorids which, as the results of recent studies, are also not closely related to each other. Gobiraptor increases diversity of oviraptorids in the Nemegt Formation and its presence confirms the successful adaptation of oviraptorids to a mesic environment.

The discovery of an extremely well preserved new juvenile specimen of Sapeornis provides more anatomical information about this basal avian, and documents the first avian specimen from the Jehol Biota with detailed foot-pad integument preserved. This is the first Sapeornis specimen with a well preserved carpal X, astragalus and calcaneum. Seven major skeletal components from five well preserved juvenile and adult skeletons of Sapeornis were measured. The allometric differences associated with growth are shown to be distinct; all linear regressions resulted in high correlation coefficients consistent with a single growth series. The number of sacral vertebrae and free caudal vertebrae vary during ontogeny, and this may indicate that all the specimens can be assigned to a single species: Sapeornis chaoyangensis.

A new Cretaceous bird ichnotaxon, Dongyangornipes sinensis ichnogen. et ichnosp. nov., is described. It is the first record of a webbed bird footprint in China. It was recovered from the early Late Cretaceous Jinhua Formation in Dongyang City, Zhejiang Province. It is characterized by comparatively small tridactyl footprints with a notably developed web structure without a hallux impression. The web impression of digits II–III is connected from the apex of digit II to the posterior third of digit III, whereas that between digits III and IV is linked from the apex of digit IV to the mid-point of digit III. Webbed footprints of Cretaceous birds have not been described previously from outside South Korea. Shorebird footprints without webbing, referred to Koreanaornis cf. hamanensis, are also present at the same site. The Dongyang bird footprint site is the southernmost locality of Mesozoic bird track sites in Asia.

Oviraptorids are a group of specialized non-avian theropod dinosaurs that were generally one to 8 m in body length. New specimens of baby oviraptorids from the Late Cretaceous of Henan Province are some of the smallest individuals known. They include diagnostic characters such as the relative position of the antorbital fenestra and the external naris, distinct opening in the premaxilla anteroventral to the external naris, antorbital fossa partly bordered by premaxilla posterodorsally, lacrimal process of premaxilla does not contact the anterodorsal process of the lacrimal, parietal almost as long as frontal; in dorsal view, posterior margin forms a straight line between the postzygapophyses in each of the fourth and fifth cervicals; femur longer than ilium. They also elucidate the ontogenetic processes of oviraptorids, including fusion of cranial elements and changes in relative body proportions. Hind limb proportions are constant in oviraptorids, regardless of absolute body size or ontogenetic stage. This suggests a sedentary lifestyle that did not involve the pursuit of similar-sized prey. The functional implications for bite force and therefore dietary preferences are better understood through the study of such small animals. The comparison of the measurements of 115 skeletons indicates that oviraptorids maintain their hind limb proportions regardless of ontogenetic stage or absolute size, which is a pattern seen more commonly in herbivores than in carnivores. This may weakly support the hypothesis that oviraptorids are herbivores rather than active carnivores.

Asymmetrical feathers have been associated with flight capability but are also found in species that do not fly, and their appearance was a major event in feather evolution. Among non-avialan theropods, they are only known in microraptorine dromaeosaurids. Here we report a new troodontid, Jianianhualong tengi gen. et sp. nov., from the Lower Cretaceous Jehol Group of China, that has anatomical features that are transitional between long-armed basal troodontids and derived short-armed ones, shedding new light on troodontid character evolution. It indicates that troodontid feathering is similar to Archaeopteryx in having large arm and leg feathers as well as frond-like tail feathering, confirming that these feathering characteristics were widely present among basal paravians. Most significantly, the taxon has the earliest known asymmetrical troodontid feathers, suggesting that feather asymmetry was ancestral to Paraves. This taxon also displays a mosaic distribution of characters like Sinusonasus, another troodontid with transitional anatomical features., Troodontids were theropod dinosaurs closely related to birds. Here, Xu and colleagues describe a new, feathered troodontid species, Jianianhualong tengi, dating from the Lower Cretaceous period in China that provides insight into troodontid mosaic evolution and paravian feathering.

Oviraptorosaurs are a bizarre group of bird-like theropod dinosaurs, the derived forms of which have shortened, toothless skulls, and which diverged from close relatives by developing peculiar feeding adaptations. Although once among the most mysterious of dinosaurs, oviraptorosaurs are becoming better understood with the discovery of many new fossils in Asia and North America. The Ganzhou area of southern China is emerging as a hotspot of oviraptorosaur discoveries, as over the past half decade five new monotypic genera have been found in the latest Cretaceous (Maastrichtian) deposits of this region. We here report a sixth diagnostic oviraptorosaur from Ganzhou, Tongtianlong limosus gen. et sp. nov., represented by a remarkably well-preserved specimen in an unusual splayed-limb and raised-head posture. Tongtianlong is a derived oviraptorid oviraptorosaur, differentiated from other species by its unique dome-like skull roof, highly convex premaxilla, and other features of the skull. The large number of oviraptorosaurs from Ganzhou, which often differ in cranial morphologies related to feeding, document an evolutionary radiation of these dinosaurs during the very latest Cretaceous of Asia, which helped establish one of the last diverse dinosaur faunas before the end-Cretaceous extinction.

A new ctenochasmatoid pterosaur, Gladocephaloideus jingangshanensis gen. et sp. nov. from the Yixian Formation of western Laioning Province is erected based on a complete skull and partial postcranial skeleton. It is characterized by following features: about 50 total teeth with sharp tips; small nasoantorbital opening, occupying approximately 13% of the skull length; ratio of prenarial length to skull length approximately 0.63. The diagnoses of the Ctenochasmatoidea and Gallodactylidae are amended based on the new taxon. Gladocephaloideus jingangshanensis is the first gallodactylid pterosaur found in Asia. Its discovery not only provides much more osteological information about the Gallodactylidae but also indicates that the ctenochasmatoid pterosaurs were highly diverse in the Early Cretaceous. The filamentous structures preserved near the dorsal and posterior margins of the posterior portion of the skull and around the neck indicate that it had an epidermal covering and may have been a warm-blooded animal.

A new Sordes-like pterosaur Jianchangopterus zhaoianus gen. et sp. nov. is erected based on a almost complete skeleton with skull preserved. It is characterized by the following characters: seven and six pairs of upper jaw and lower jaw teeth respectively; the development of a recess on maxilla; the evenness of the dental margin in lateral view; a distinct central ridge along dorsal surface of the mandibular symphysis; wing phalanx 4 with strongly curved shaft approximately 96% the length of the wing phalanx 1. The discovery of a Sordes-like pterosaur Jianchangopterus, and other taxa from the same formation indicates that pterosaurs reached great diversities during the Middle to Upper Jurassic period.

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.

A partial skeleton of the ornithomimid dinosaur, discovered from the Late Cretaceous Qiupa Formation of Luanchuan County, Tantou Basin, Henan Province, China, is described here and assigned to a new genus and species, Qiupalong henanensis, with unique features (a notch on the lateral surface of the lateral posterior process of the proximal end of tibia and a small pit at the contact between astragalus and calcaneum). A phylogenetic analysis in this study suggests that it is a derived ornithomimid and form a monophyly with North American ornithomimids (Struthiomimus altus and Ornithomimus edmontonicus), sharing two characters (straight pubic shaft and large acute angle between pubic shaft and boot). Some characters (small anterior process of the pubic boot and curved pedal unguals) are seen in basal ornithomimosaurs as well, but these features in Q. henanensis are reversal. Qiupalong is the first definitive ornithomimid from outside of the Gobi Desert and is the southern-most occurrence of Late Cretaceous ornithomimid from eastern Asia, demonstrating southern extension of ornithomimid distribution in Asia.

A new troodontid dinosaur, Xixiasaurus henanensis gen. et sp. nov., from the Upper Cretaceous Majiacun Formation of the Xixia Basin, Henan Province, is erected, based on a partial skull. It is characterized by bearing 22 maxillary teeth, a distinct opening on the lateral surface of the base of nasal process of the premaxilla, the rostral end of the upper jaw forming a tapered U-shape, and the mandibular symphyseal region slightly inflected medially. Xixiasaurus is most closely related to the Mongolian Byronosaurus among troodontids. Byronosaurus, Urbacodon, and Xixiasaurus may form a new clade, suggesting an endemic radiation of troodontids across Asia, including multiple taxa without dental serrations. The discovery of Xixiasaurus in the Xixia Basin may imply that the Xixiasaurus-bearing Majiacun Formation is Campanian in age.

Most birds sit on their eggs during incubation, a behaviour that likely evolved among non-avian dinosaurs. Several ‘brooding' specimens of smaller species of oviraptorosaurs and troodontids reveal these non-avian theropods sat on their eggs, although little is known of incubation behaviour in larger theropod species. Here we examine egg clutches over a large body size range of oviraptorosaurs in order to understand the potential effect of body size on incubation behaviour. Eggshell porosity indicates that the eggs of all oviraptorosaurs were exposed in the nest, similar to brooding birds. Although all oviraptorosaur clutches consist of radially arranged eggs in a ring configuration, clutch morphology varies in that the central opening is small or absent in the smallest species, becomes significantly larger in larger species, and occupies most of the nest area in giant species. Our results suggest that the smallest oviraptorosaurs probably sat directly on the eggs, whereas with increasing body size more weight was likely carried by the central opening, reducing or eliminating the load on the eggs and still potentially allowing for some contact during incubation in giant species. This adaptation, not seen in birds, appears to remove the body size constraints of incubation behaviour in giant oviraptorosaurs.

In 1990, five well-preserved pterosaur trackways were discovered in the Kitadani Formation (Lower Cretaceous) of the Kitadani Dinosaur Quarry, Fukui Prefecture, Japan. They occur on the surface of an isolated dark grey siltstone slab (70 × 50 cm) along with amphibian and bird tracks as well as feeding marks. All pterosaur trackways (a total of 64 imprints) show a clear quadrupedal gait pattern comprising manus and pes prints which reflect their detailed anatomy of the feet. Manus and pes imprint is very small, average 22.6 mm and 21.9 mm long, respectively. The manus has an anteriorly oriented digit I imprint with a medially oriented hook-like sharp claw mark, which makes a high divarication (average 155.4°) between the posteriorly oriented digit III imprint. The high digital abduction clearly shows that digit I of the manus could be more hyper-extended anteriorly than previously thought: spreading the digits as much as possible would provide a more stable contact with substrate as well as better support the center of pterosaur body mass displaced anteriorly. The interdigital webbing of the pes imprint extends from the metatarso-phalangeal joint near to the bases of four claws. As these features clearly distinguish the Kitadani pterosaur trackways from five known ichnospecies of Pteraichnus, we assign them to a new ichnospecies, Pteraichnus nipponensis. Abundant small pterosaur ichnotaxa from Spain, Korea, and Japan indicate that many small pterodactyloid pterosaur species existed in the Early Cretaceous although there is no single skeletal datum yet.

A new boreopterid pterosaur: Zhenyuanopterus longirostris gen. et sp. nov. from the Yixian Formation of western Liaoning is erected, based on the complete skeleton with a skull and lower jaws preserved. It is characterized by: a large boreopterid pterosaur with a high number of teeth, where the anterior teeth are much larger than posterior ones; the length of the dorsal + sacral vertebrae is nearly half the length of the skull; ratio of the length of the humerus to metacarpal IV is approximately 91% and the, humerus, femur and third wing phalanx are all equal in length and the feet are specially small. It represents the largest boroepterid pterosaur discovered from western Liaoning and its surrounding areas so far

The fossil record is a unique source of evidence for important evolutionary phenomena such as transitions between major clades. Frustratingly, relevant fossils are still comparatively rare, most transitions have yet to be documented in detail and the mechanisms that underpin such events, typified by rapid large scale changes and for which microevolutionary processes seem insufficient, are still unclear. A new pterosaur (Mesozoic flying reptile) from the Middle Jurassic of China,Darwinopterus modularisgen. et sp. nov., provides the first insights into a prominent, but poorly understood transition between basal, predominantly long-tailed pterosaurs and the more derived, exclusively short-tailed pterodactyloids.Darwinopterusexhibits a remarkable ‘modular’ combination of characters: the skull and neck are typically pterodactyloid, exhibiting numerous derived character states, while the remainder of the skeleton is almost completely plesiomorphic and identical to that of basal pterosaurs. This pattern supports the idea that modules, tightly integrated complexes of characters with discrete, semi-independent and temporally persistent histories, were the principal focus of natural selection and played a leading role in evolutionary transitions.

New material of dsungaripterid pterosaurs from the Early Cretaceous of Tatal, western Mongolia, allows the diagnoses of Dsungaripteridae andNoripterusto be amended. All pterosaurs found at Tatal belong to Dsungaripteridae (eitherDsungaripterusorNoripterus). The namePhobetoris a junior synonym ofNoripterus. The differing shapes of the anterior tips of skulls, differing tooth morphologies and the coexistence of bothDsungaripterusandNoripterusmay imply that they occupied distinct ecological niches.

A new sauropod dinosaur Baotianmansaurus henanensis gen. et sp. nov. from the Cretaceous Gaogou Formation of Neixiang, Henan Province is erected. It is characterized by somphospondylous presacral vertebrae; a highly-developed lamina system on the dorsal vertebrae; transverse process supported by four laminae; and the dorsal portion of the anterior centroparapophyseal lamina is bifurcated, with a small branch extending to the ventral surface of the prezygapophysis. It represents a new titanosauriform sauropod.

A new basal non-pterodactyloid pterosaur, Changchengopterus pani gen. et sp. nov., is erected, on the basis of a nearly complete postcranial skeleton. The new taxon is distinguished by relatively short extensions of the prezygapophyses, postzygapophyses and haemal arches of the caudal vertebrae; a humerus that has a subtriangular deltopectoral crest; limb elements that decrease in length in the following order: ulna> wing-phalange 2 > wing-phalange 3 = wing-phalange 1>humerus >tibia>femur>wing-metacarpal. Phylogenetic analysis suggests that Changchengopterus is a basal member of rhamphorhynchoids, and more closely related to Dorygnathus than to other rhamphorhychoids. The geological age of the Changchengopterus-bearing sediments is no latter than the end of the Late Jurassic and it is possible Middle Jurassic.

This paper briefly introduces the basic concepts of a new field of plant pathology——molecular epidemiology of plant diseases.Molecular biology and biotechnology have been widely used in many areas of epidemiology.In addition to identify the disease-causal pathogens,some molecular approaches have been used to efficiently quantify the initial inoculum causing disease epidemics,demonstrating the advantages over the conventional methods.Population genetics provides useful tools to infer the pathways of pathogen long-distance dispersal and disease spread,and may offer strong evidences of pathogen migration as complement of conventional methods.These bio-techniques have been also used to monitor the spatial and temporal developments of diseases and pathogen populations,to study the pathogen long-term evolution and its effects on disease epidemics,and to reveal the competitions between different pathogen genotypes and the resulting consequences of disease epidemics.Using molecular approaches,screening host resistance will become more efficient.More valuable disease control strategies will become applicable with applications of bio-techniques.Macro-and Micro-approaches will be combined as advantages of methodology,demonstrating a huge potential to promote the research in epidemiology.

The Nyctosaurus specimen KJ1 was reconstructed under the hypothesis that there is a membrane attached to the crest; the so-called headsail crest. The aerodynamic forces and moment acting on the headsail crest were analyzed. It was shown that KJ1 might adjust the angle of the headsail crest relative to the air current as one way to generate thrust (one of the aerodynamic forces, used to overcome body drag in forward flight) and that the magnitude of the thrust and moment could vary with the gesture angle and the relative location between the aerodynamic center of the headsail crest and body's center of gravity. Three scenarios were tested for comparison: the crest with membrane attachment, the crest without membrane attachment and the absence of a cranial crest. It was shown that the aerodynamic characteristics (increasing, maintaining and decreasing thrusts and moment) would have almost disappear in flight for the crest without membrane attachment and was non-existent without the cranial crest. It is suggested from aerodynamics evidence alone that Nyctosaurus specimen KJ1 had a membrane attached to the crest and used this reconstructed form for auxiliary flight control.

A reassessment of the systematic relationships of pterosaurs from the Lower Cretaceous Yixian Formation of Liaoning Province, China, shows that Dendrorhynchoides should be reassigned to the Anurognathidae (“Rhamphorhynchoidea”) and that Eosipterus possibly belongs within Ctenochasmatidae (Pterodactyloidea). These pterosaurs formed an integral part of a diverse community that inhabited lowland terrestrial environments in the region of northeast China in the Early Cretaceous. A new compilation of data for the Lower Cretaceous hints at a broad differentiation between pterosaurs that lived in continental habitats (anurognathids, ctenochasmatoids, dsungaripteroids) and those that frequented marine environments (ornithocheiroids). Moreover, there is evidence of further differentiation within continental habitats, between pterosaurs living in lowland and coastal regions (anurognathids. ctenochasmatoids) and those living in more inland environments (dsungaripteroids). The temporal and geographical range extensions for high rank taxa that are implied by the Yixian pterosaurs further emphasise the incompleteness and unevenness of the pterosaur fossil record and its unreliability for biostratigraphic zonation. Eine Neubewertung der systematischen Stellung der Flugsaurier von der unterkretazischen Yixian-Formation der Provinz Liaoning, China, zeigt, dass Dendrorhynchoides den Anurognathiden (“Rhamphorhynchoidea”) zugeordnet werden kann und dass Eosipterus vermutlich zu den Ctenochasmatiden (Pterodactyloidea) gehört. Diese beiden Flugsaurier bilden einen integralen Bestandteil einer diversen Fauna, die in der Unteren Kreide ein terrestrisches Flachland-Ökosystem im Nordosten Chinas bewohnte. Fasst man die für die Untere Kreide verfügbaren Daten zusammen, so zeigt sich eine weitgehende Differenzierung zwischen Flugsauriern, die überwiegend in kontinentalen Ökosystemen lebten (Anurognathidae, Ctenochasmatoidea, Dsungaripteroidea) und jenen, die auch oft in marinen Bereichen auftreten (Ornithocheiroidea). Darüber hinaus gibt es auch Hinweise auf eine Differenzierung innerhalb der kontinentalen Habitate, zwischen Pterosauriern, die sich in den Ebenen und küstennahen Bereichen aufhielten (Anurognathidae, Ctenochasmatoidea) und den Bewohnern von mehr küstenfernen Ökosystemen (Dsungaripteroidea). Die von den Taxa der Yixian-Formation angezeigte Erweiterung der stratigraphischen und geographischen Reichweite für Taxa höheren Ranges unterstreichen die Unvollständigkeit und Unausgewogenheit des Fossilberichtes der Flugsaurier und seine Unzulänglichkeit für biostratigraphische Zonierungen. doi:10.1002/mmng.20000030109

In 2004, fifty new pterosaur tracks were discovered in the Hasandong Formation (Lower Cretaceous), South Korea. They are preserved as natural casts on the surface of an isolated dark grey mudstone block (70 × 50 cm). Manus and pes imprints are very small, averaging 25.6 mm and 25.7 mm long, respectively. The manus imprints (N = 25) are tridactyl and digit I, II, III are strongly asymmetric. Fully plantigrade pes imprints (N = 25) were left by elongate metatarsals with short four digits (the ratio of digit to whole pes length is 2.6). There is no trace of the 5th phalanx of the pes. As these features clearly distinguish the Hadong tracks from the type species of the ichnogenus Pteraichnus, we assign them to a new species, Pteraichnus koreanensis. They are stratigraphically the oldest pterosaur tracks in Korea and are distinguished by size and morphology from the two pterosaur ichnotaxa, Haenamichnus uhangriensis and Pteraichnus isp., previously reported from the Uhangri and Haman formations. Pteraichnus koreanensis is the smallest pterosaur track currently reported from Asia.

A psittacosaurid dinosaur from western Liaoning, China, possessing a pathological fibula is described. The pathological fibula is significantly different from a normal fibula, being shorter and much stouter, and with a distinct swelling on the shaft. The swollen portion (representing a mass of necrotic bone) of the fibula indicates that the animal survived for a relatively long time after becoming diseased, implying that the injuries to the fibula were not fatal, as has also been noted for some theropod dinosaurs. The pathological fibula may have been caused by the tubercle bacillus.