New information on the anatomy of the Chinese Early Cretaceous Bohaiornithidae (Aves: Enantiornithes) from a subadult specimen of Zhouornis hani

Enantiornithines are the most diverse avian clade in the Cretaceous. However, morphological specializations indicative of specific ecological roles are not well known for this clade. Here we report on an exquisitely well-preserved specimen from the Lower Cretaceous Jehol Group of northeastern China, which pedal morphology is suggestive of a unique ecological specialization within Enantiornithes. The morphology of the new specimen is largely indistinguishable from that of the holotype of the bohaiornithid enantiornithine Zhouornis hani, albeit the latter is somewhat larger. The new specimen provides important and previously unknown details of the skull of Zhouornis hani, which add to the limited knowledge about the cranial anatomy and evolution of enantiornithines. The information offered by the new specimen also augments our understanding of the postcranial morphology of bohaiornithid enantiornithines, a clade that has been only recently recognized. With the description of this specimen, Zhouornis hani becomes one of the most anatomically complete known enantiornithine species, which will facilitate future morphological studies

Diversity and evolution of the Confuciusornithidae: Evidence from a new 131- million-year-old specimen from the Huajiying Formation in NE China

The Huajiying Formation contains the earliest deposits of the Jehol Biota, representing the world’s second oldest avifauna. This avifauna includes the early confuciusornithid Eoconfuciusornis zhengi, the oldest occurrence of this clade and one of the earliest divergences of pygostylian birds. Although E. zhengi shows unique traits, the holotype’s immature age makes comparisons with the better known Confuciusornis sanctus problematic. As a result, the taxonomic validity of E. zhengi is controversial. We describe a small, osteologically adult confuciusornithid from the same deposits as E. zhengi. The new fossil is most similar to E. zhengi but also shares traits with the stratigraphically younger Confuciusornis. The humerus of the new fossil is straighter and more slender, and bears a less dorsally-developed deltopectoral crest compared with similarly-sized and smaller specimens of Confuciusornis. The morphology of the humerus is intermediate between E. zhengi and Confuciusornis and its proximal portion is pierced by a small deltopectoral foramen, absent in the holotype of E. zhengi. However, this foramen is much smaller than in any other confuciusornithid. Shape analyses (geometric morphometrics) of the humerus of confuciusornithids of different ages and representatives of other basal avians and closely-related non-avian theropods supports our observations and indicate that the humeral differences between the holotype of E. zhengi and the new specimen are not easily explained as ontogenetic variation within a single species. However, the limited number of early confuciursornithids does not allow us to confidently interpret such differences as interspecific. Nonetheless, these analyses support the morphological distinctiveness of the early confuciusornithids from the Huajiying Formation and suggest a stepwise acquisition of the unique humeral morphology of ConfuciusornithidaeGN is supported by a PG Scholarship/Studentship from The Alumni Foundation, University of Bristol, UK. JML is supported by the Spanish MINECO, Project CGL-2013-42643. Innovative Team Program of the Beijing Academy of Science and Technology, the Beijing Millions of Talents Project in the New Century, the National Natural Science Foundation of China (No. 41602006), and theBeijing Natural Science Foundation (No. 5174032) provided funding for this researc

onthesystematicpositionofeosipterusyangijietji1997amongpterodactyloids

A comparison of the new specimen with the holotype of Eosipterus from western Liaoning Province indicates that Eosipterus is a valid genus, which belongs to the family Ctenochasmatidae. The revised diagnosis of Eosipterus includes the wing span is less than 1.25 meters, the length of the ulna is nearly equal to these of wing phalanx 2 and the tibia, humerus is longer than tibia, and the ratio of metatarsal to tibia is approximately 0.40

newmaterialofthepterosaureopteranodonfromtheearlycretaceousyixianformationwesternliaoningchina

根据新材料，对始无齿翼龙的特征进行了修订：中部颈椎体没有神经棘；肱骨三角嵴的长度与肱骨长度之比率约为0．2．5：翼掌骨的长度与第二翼指骨的长度几乎相等；第二翼指骨与第一翼指骨的长度之比率约为0．76。始无齿翼龙的新标本与正型稍微不同，可能由个体发育所引起

New specimens of Anchiornis huxleyi (Theropoda, Paraves) from the late Jurassic of northeastern China. (Bulletin of the American Museum of Natural History, no. 411)

66 pages : illustrations (chiefly color) ; 26 cm.Four new specimens of Anchiornis huxleyi (PKUP V1068, BMNHC PH804, BMNHC PH822, and BMNHC PH823) were recently recovered from the late Jurassic fossil beds of the Tiaojishan Formation in northeastern China. These new specimens are almost completely preserved with cranial and postcranial skeletons. Morphological features of Anchiornis huxleyi have implications for paravian character evolution and provide insights into the relationships of major paravian lineages. Anchiornis huxleyi shares derived features with avialans, such as a straight nasal process of the premaxilla and the absence of an external mandibular fenestra in lateral view. However, Anchiornis huxleyi lacks several derived deinonychosaurian features, including a laterally exposed splenial and a specialized raptorial pedal digit II. Morphological comparisons strongly suggest Anchiornis is more closely related to avialans than to deinonychosaurians or troodontids. Anchiornis huxleyi exhibits many conservative paravian features, and closely resembles Archaeopteryx and other Jurassic paravians from Jianchang County, such as Xiaotingia and Eosinopteryx. The other Jianchang paravian, Aurornis xui, is likely a junior synonym of Anchiornis huxleyi