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K–P transition in Brazil. ( 英 文 ). Barbosa J A;Kellner A W A; Viana M S S3. Proceedings ofthe Royal Society B: Biological Sciences, 2008,275(1641): 1385-1391The discovery of a new dyrosaurid crocodylomorphfrom the well-dated Palaeocene depositsof northeastern Brazil sheds new light on theevolutionary history of this extinct group of marinecrocodylomorphs that have survived theCretaceous–Palaeogene (K–P) extinction crisis.Guarinisuchus munizi, the most complete memberof this group collected in South America sofar, is closely related to the African forms, andthis fact suggests that dyrosaurids had crossedthe Atlantic Ocean before the K–P boundary anddispersed from there to North America and otherparts of South America. This discovery alsosuggests that on the coast of northeastern Brazil,dyrosaurids replaced the pre-existing Late Cretaceousfauna of diversified mosasaurs, a group ofmarine lizards, after the K–P extinction event,becoming the main predators, together withsharks, in shallow marine Palaeocene environments.More detailed stratigraphic records anddetailed dating of the deposits with dyrosauridsare necessary to correlate this particular patternfound in the ancient northeastern Brazilian coastwithin the evolution of the group, especially inAfrica.The discovery of a new dyrosaurid crocodylomorphfrom the well-dated Palaeocene depositsof northeastern Brazil sheds new light on theevolutionary history of this extinct group of marinecrocodylomorphs that have survived theCretaceous–Palaeogene (K–P) extinction crisis.Guarinisuchus munizi, the most complete memberof this group collected in South America sofar, is closely related to the African forms, andthis fact suggests that dyrosaurids had crossedthe Atlantic Ocean before the K–P boundary anddispersed from there to North America and otherparts of South America. This discovery alsosuggests that on the coast of northeastern Brazil,dyrosaurids replaced the pre-existing Late Cretaceousfauna of diversified mosasaurs, a group ofmarine lizards, after the K–P extinction event,becoming the main predators, together withsharks, in shallow marine Palaeocene environments.More detailed stratigraphic records anddetailed dating of the deposits with dyrosauridsare necessary to correlate this particular patternfound in the ancient northeastern Brazilian coastwithin the evolution of the group, especially inAfrica.The discovery of a new dyrosaurid crocodylomorphfrom the well-dated Palaeocene depositsof northeastern Brazil sheds new light on theevolutionary history of this extinct group of marinecrocodylomorphs that have survived theCretaceous–Palaeogene (K–P) extinction crisis.Guarinisuchus munizi, the most complete memberof this group collected in South America sofar, is closely related to the African forms, andthis fact suggests that dyrosaurids had crossedthe Atlantic Ocean before the K–P boundary anddispersed from there to North America and otherparts of South America. This discovery alsosuggests that on the coast of northeastern Brazil,dyrosaurids replaced the pre-existing Late Cretaceousfauna of diversified mosasaurs, a group ofmarine lizards, after the K–P extinction event,becoming the main predators, together withsharks, in shallow marine Palaeocene environments.More detailed stratigraphic records anddetailed dating of the deposits with dyrosauridsare necessary to correlate this particular patternfound in the ancient northeastern Brazilian coastwithin the evolution of the group, especially inAfrica.2008040444中 二 叠 世 四 足 类 化 石 记 录 全 球 缺 失 = A globalhiatus in the Middle Permian tetrapod fossil record.( 英 文 ). Lucas S G. Stratigraphy, 2004,1(1): 47-64For about a half century, most vertebrate paleontologistshave correlated the youngest Permiantetrapod assemblages inNorth America,which are from the San Angelo, Flowerpot andChickasha formations in Texas-Oklahoma, to theoldest therapsid-bearing assemblages of the RussianKazanian. This correlation was not based onshared low-level taxa (genera and species),buton the supposed therapsids in the American faunasand the presence of some “counterparts”(equivalent evolutionary grade) amongtheAmericanand Russian captorhinids and caseid pelycosaurs.Marinebiostratigraphy indicates that theyoungest tetrapod assemblages in Texas-Oklahoma are of Kungurian (late Leonardian)age, whereas the base of the Kazanian is noolder than late Roadian. Thus, a veryreal hiatusin the global tetrapod record, previously namedOlson’s gap, is evident between the youngest,pelycosaur-dominated assemblagesof NorthAmerica and the oldest, therapsid-dominatedtetrapod assemblages of Russia. This hiatus isequivalent to most of Roadian time, and is atleast two million years long. A review of theglobal record of Permian tetrapod body fossilsand footprints revealsthat this is a hiatus ofglobal extent. Olson’s gap corresponds to a significantremodelling of the Permian tetrapodfauna.2008040445意 大 利 Friuli 地 区 晚 三 叠 世 Langobardisaurusrossii 的 修 订 = A revision of Langobardisaurusrossii Bizzarini and Muscio, 1995from the Late Triassic of Friuli (Italy). ( 英 文 ).136