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1.
The Late Jurassic Archaeopterygidae, comprising the iconic genus Archaeopteryx, is altogether among the earliest, basalmost and best-known Mesozoic avian taxa. The geographic distribution of Archaeopteryx is hitherto restricted to a limited region of southern Germany, probably due to preservation biases. Here we describe a tooth sorted among the more than 35,000 isolated teeth found by sieving sediments from the Cherves-de-Cognac locality (western France, Lower Cretaceous). This tooth crown is morphologically similar to teeth of the German specimens of Archaeopteryx (sensu lato), despite minor differences. The Cherves-de-Cognac tooth differs much more importantly from all other known taxa. It shares with different specimens of Archaeopteryx the general tooth size, recurved shape affecting apical third of crown, thin apical-mesial carina, constriction at base of crown giving distinctive S shape of distal edge in profile, absence of other ornamentation or serration, and shape of crown section. Incidentally, former assignments of teeth from the Upper Jurassic of Guimarota (Portugal) to cf. Archaeopteryx are unwarranted, as those teeth markedly differ from the Archaeopterygidae in several crucial features. We assign the new tooth to the family Archaeopterygidae, the earliest European birds, making it the first member of the family in Europe outside Germany, and extending its temporal occurrence to the early Cretaceous. 相似文献
2.
Ornithuromorph birds (the clade which includes modern avian radiation) first appeared in the Early Cretaceous in Asia and achieved a great diversity during the latest ages of the Late Cretaceous (Campanian and Maastrichtian). The evolutionary history of orithuromorphs during the first 17 MYAs of the Late Cretaceous (Cenomanian to Santonian ages) remains very poorly known, as the fossil record for this time interval is largely restricted to several isolated finds of the classic avian genus Ichthyornis in North America. Here we describe an isolated distal tibiotarsus of an evolutionary advanced bird, morphologically similar to Ichthyornis, from the middle Cenomanian of Saratov Province, European Russia. This is the first documentation of an Ichthyornis-like bird in the Old World. The find further constitutes only the second pre-Campanian record of the Late Cretaceous Ornithuromorpha in Eurasia, the second record of Cenomanian birds in Russia. This discovery shows that Ichthyornis-like birds enjoyed a wide geographical distribution as early as the beginning of the Late Cretaceous. Given that the earliest and the most primitive ornithuromorph birds are known from Asia, the new find supports a Eurasian origin for Ichthyornithidae. 相似文献
3.
Tail anatomy of unenlagiid theropods remains poorly known. The most complete and informative taxon of this family is Buitreraptor gonzalezorum from the Upper Cretaceous of Rio Negro province, Argentina. The aim of the present contribution is to carry out an analysis of the tail anatomy of Buitreraptor based on its holotype and a newly collected specimen as well. Similarities shared by Buitreraptor, Rahonavis, Anchiornis and Archaeopteryx include: mid-caudal vertebrae with postzygapophyses longer than prezygapophyses, and mid-caudal centra with a system of lateral laminae and concavities. Preservation of paravian skeletons, as well as muscular reconstruction, indicate the presence of two different functional sections of the tail. This contribution sheds light on paravian tail evolution and provides new data on tail changes that occurred along the theropod line towards modern birds. 相似文献
4.
Diverse new material of mantises found in the Cretaceous amber-bearing deposits from Lebanon (Barremian), Spain (Albian), and Myanmar (Albian–Cenomanian) are described and figured. The Lebanese and Spanish forms are nymphs; while the one from Myanmar is an adult specimen. The Lebanese nymph corresponds to a new specimen of Burmantis lebanensis Grimaldi, 2003 while the adult Burmese (Myanmar) specimen belongs to the new species Burmantis zherikhini. The Spanish specimen represents a new genus and species and is established as Aragonimantis aenigma, but is considered family incertae sedis. The Spanish specimen is the first record of Mesozoic mantises from western-European amber deposits. A revised phylogenetic hypothesis for Cretaceous mantises is proposed. 相似文献
5.
A new species belonging to the extant dermestid genus Attagenus, Attagenus burmiticus sp. nov., is described and illustrated based on a well-preserved specimen from the Upper Cretaceous Burmese amber. The discovery suggests that Attagenus is an ancient group, originating as early as in the mid-Cretaceous. Along with another species of Attagenus known from the Upper Cretaceous New Jersey amber, it implies that Attagenus were widespread in the Mesoozic. 相似文献
6.
Seeds preserved in association with the holotype of Jeholornis prima provided the first direct evidence of granivory in any Mesozoic bird. Although this long boney-tailed bird also displays several morphological indicators correlated with herbivory such as reduced dentition and a deep mandible, Jeholornis has not been previously reported to possess a gastric mill. However, this feature is commonly linked to herbivory in theropod dinosaurs and present in at least one sympatric ornithuromorph and the basal pygostylian Sapeornis, which also preserve direct evidence of granivory. Here we describe gastrolith masses preserved in five specimens of Jeholornis. The cluster of gizzard stones is nearly identical in each specimen, consisting of a tightly associated mass of proportionately small stones. Three previously undescribed specimens preserving seeds are also identified. Unlike in Sapeornis and a previously described ornithuromorph, no specimen of Jeholornis preserves both seeds and gastroliths. This may be due to the fact that, unlike in other Early Cretaceous birds, the seeds preserved in specimens of Jeholornis are found in the abdomen, suggesting that Jeholornis may have resembled extant ratites in lacking an esophageal crop. Consistent differences in the preservation and morphology of the gastrolith mass between Jeholornis and other early birds hint at subtle variations in alimentary function among basal lineages. Differences in ingested seed morphology among taxa in turn suggest these functional variations may be at least partially related to differences in diet. 相似文献
7.
中国发现世界上最原始的鸟类化石：华美金凤鸟（新属、新种） 总被引：3，自引：0，他引：3
始祖鸟的发现被认为是19世纪最重要的科学发现之一,迄今为止共发现了7枚保存骨骼、羽毛印痕的化石标本和1枚单根羽毛化石标本。由于始祖鸟既显示了明显的爬行动物的特征又保存了精美的羽毛,140多年来人们一直将其作为介于恐龙与鸟类之间的“中间环节”(“missing link”),但更倾向认为它是世界上最古老的鸟,或鸟类的始祖。由于始祖鸟化石稀少,加之地理分布十分局限,长期以来国际上一直围绕鸟类起源问题展开了激烈的争论,提出了各种各样的假说。直到20世纪90年代,在中国辽西晚中生代地层中发现了大量长羽毛的恐龙和原始鸟类化石,有力地支持了鸟类起源于小型兽脚类恐龙的学术观点,使赫 140多年前提出的“假说”成为当今国际科学界占主流地位的学说和理论,基本解决了长期困扰国际科学界的鸟类起源问题,遗憾的是,在过去的几年中,中国一直没有发现与德国始祖鸟十分接近或与德国始祖鸟处于同样进化水平的原始鸟类化石,这种缺憾使我们难以对鸟类定义问题进行深入的研究和探讨,2002年,笔者等在中国辽西早白垩世断层中发现了2种初鸟类化石,即中华神州鸟和东方吉祥鸟。通过比较解剖学研究和支序分析,这2种初鸟类要比始祖鸟略微进步一些,在研究鸟类的早期演化方面具有重要意义;但仍然难以对鸟类定义问题作进一步研究。本文首次报道了一件采自中国河北省丰宁县龙凤山桥头组的初鸟类化石——华美金凤鸟（新属、新种）(Jinfengopteryx elegans gen.et sp.nov),与其共生的化石有Lycoptera davidi,Peipiaosteus pani,yanosteus longidorsalis（鱼类）;Jibeinia luanhera,Protopteryx fengningensis(鸟类）;Ephemeropsis trisetalis(昆虫）及少量植物。支序分析表明,华美金凤鸟处于初鸟类谱系树的基部,比始祖鸟略微原始,与后者为姊妹群关系。奔龙等兽脚类恐龙是它们的外类群。金凤鸟、始祖鸟是中华神州鸟等原始鸟类的外类群。这说明华美金凤鸟处在恐龙向鸟类演化过程中一个非常关键的位置,是世界上迄今所发现的最原始的初鸟类。华美金凤鸟的发现在研究鸟类起源、恐龙-鸟类的系统关系等方面具有重要的科学意义。 相似文献
8.
Early Cretaceous elasmobranchs still are very insufficiently known despite all progress that has been accomplished in recent years. Here, a small elasmobranch assemblage is presented from the Valanginian of Austria that contributes significantly to a better understanding of early Cretaceous elasmobranch diversity. The new assemblage comprises two new carcharhiniform sharks, Altusmirus triquetrus gen. et sp. nov. and Fornicatus austriacus gen. et sp. nov., a new orectolobiform shark, Similiteroscyllium iniquus gen. et sp. nov., and a galeomorph shark tooth of uncertain affinities. The recent identification of Similiteroscyllium gen. nov. has shown that it has strong similarities with Ornatoscyllium rugasimulatum from the Lower Cretaceous of France. Significant differences of the tooth morphology of O. rugasimulatum and the type specimen O. freemani justify full reconsideration of the systematic position of O. rugasimulatum and require it to be reassigned to Similiteroscyllium gen. nov. described in this paper. The new assemblage described here, and those from the Valanginian of France and Poland comprising 30 additional taxa, indicates that Early Cretaceous elasmobranch diversity was significantly higher than previously assumed. Consequently, the supposed diversity decline of elasmobranchs across the Jurassic-Cretaceous boundary represents a collecting bias rather than a real pattern. 相似文献
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10.
There are a growing number of Early Cretaceous avian tracks and trackways from around the world, with Asia (China and Korea) having the largest reported number and diversity of Mesozoic avian traces to date, and these new discoveries are increasing the Early Cretaceous avian ichnodivesrity of Laurasia. Here we report on a new Lower Cretaceous avian track locality in the Guanshan area, Yongjing County, Gansu Province, northwest China, and on a novel ichnospecies of Koreanaornis, Koreanaornis lii ichnosp. nov. Koreananornis lii is distinct from other Koreanaornipodidae in that it possesses a consistently wider digit divarication than previously described tridactyl tracks, and possess a short, small, posteromedially oriented hallux that displays a different orientation than that seen in Koreanaornis hamanensis. The lack of linear and angular data reported for digit I traces of many avian ichnotaxa has the potential to give misleading results in multivariate statistical analyses. Also, the wide divarication of Koreanaornis lii causes the ichnotaxon to not group with other Koreanornipodidae in multivariate analyses, but with Ignotornidae. Despite the results of the analyses, K. lii is morphologically distinct from these ichnotaxa. The results demonstrate that relying solely on multivariate statistical analyses without careful examination of footprint morphology will result in erroneous ichnospecies groupings. While new vertebrate ichnotaxa discoveries from Asia may support the hypotheses of the presence of a unique and endemic Asian vertebrate ichnofauna during the Cretaceous, the recent discovery of skeletal remains interpreted to be of a volant wading bird from the Early Cretaceous, and recent reports of tracks from volant avians, could suggest that flighted avians of the shore- and wading bird ecotypes could have had a Laurasian-wide distribution during the Early Cretaceous. However, strong convergence in foot morphology of shore- and wading birds suggests that avian ichnotaxa found in both present-day Asia and North America may have been made by birds endemic to eastern and western Laurasia during the Early Cretaceous. 相似文献
11.
A new species of Elcanidae (Orthoptera: Elcanoidea), Panorpidium yixianensis sp. nov., is described based on two new specimens from the Lower Cretaceous Yixian Formation of northeastern China. It differs from other species in forewing characters and spines on the hind tibiae. In addition, a new specimen Burmelcana sp., is described and figured based on an amber inclusion from the mid-Cretaceous Burmese (Myanmar) amber. P. yixianensis sp. nov. represents the first definite record of Elcanidae in the Early Cretaceous Jehol biota, and Panorpidium is the only genus of Ensifera to be found in the Early Cretaceous faunas of England, Russia and China. 相似文献
12.
A new polypore fungus beetle is described and figured from an individual preserved in Upper Cretaceous (Cenomanian, ca. 99 Ma) amber from northern Myanmar. Cretosynstrophus archaicus gen. et sp. nov. is confidently placed in the extant subfamily Eustrophinae based on its elongate oval body and pronotum with two basal, sublinear impressions. It shares several characters belonging to two Recent tribes (Eustrophini and Holostrophini), but it cannot be attributed to either of them. Together with other tetratomid genera from the Cretaceous, the new discovery implies that the Recent small family Tetratomidae is much more diverse and more widespread than previously documented. In addition, a morphological similarity between Cretosynstrophus and extant Synstrophus suggests a similar fungi feeding habit for Cretosynstrophus, highlighting an ancient association between tetratomid beetles and fungi in the Mesozoic. 相似文献
13.
A taxon of the Stenophlebiidae, Yixianstenophlebia magnifica gen. et sp. nov., is described from the Lower Cretaceous Yixian Formation at Liutiaogou, Ningcheng County, Inner Mongolia of China. Its closest relative is the Late Jurassic European genus Stenophlebia. This new discovery is helpful to understand the Jehol Biota assemblage at Liutiaogou Locality. It also confirms that the Stenophlebiidae was a very diverse and widespread family during the Early Cretaceous. The causes of its extinction in the Late Cretaceous remain enigmatic. 相似文献
14.
Rapid radiation of the Bittacidae during the Jurassic resulted in high diversity within this family of Mecoptera. More than 40 species within 23 genera have been described from this period. However, around the end of the Jurassic the abundance and diversity of Bittacidae decreased and only seven species in five genera are known to date from the Cretaceous. A new specimen from the basal Cretaceous of England, Tytthobittacus jarzembowski sp. nov., described here, represents the eighth species and the second fossil representative of this family from the European Cretaceous. This hangingfly belongs to an extant and relictual genus previously known only from Australia. The paper also includes a review of all known Cretaceous bittacids and a re-examination of European species Antiquanabittacus nanus Petrulevičius and Jarzembowski, 2004. 相似文献
15.
Burmese amber has recently provided some detailed glimpses of plumage, soft tissues, and osteology of juvenile enantiornithine birds, but these insights have been restricted to isolated wing apices. Here we describe nearly half of a hatchling individual, based on osteological and soft tissue data obtained from the skull, neck, feet, and wing, and identified as a member of the extinct avian clade Enantiornithes. Preserved soft tissue provides the unique opportunity to observe the external opening of the ear, the eyelid, and fine details of tarsal scutellation. The new amber specimen yields the most complete view of hatchling plumage and integument yet to be recovered from the Cretaceous, including details of pterylosis, feather microstructure, and pigmentation patterns. The hatchling was encapsulated during the earliest stages of its feather production, providing a point for comparisons to other forms of body fossils, as well as isolated feathers found in Cretaceous ambers. The plumage preserves an unusual combination of precocial and altricial features unlike any living hatchling bird, having functional remiges combined with sparse body feathers. Unusual feather morphotypes on the legs, feet, and tail suggest that first generation feathers in the Enantiornithes may have been much more like contour feathers than the natal down observed in many modern birds. However, these regions also preserve filamentous feathers that appear comparable to the protofeathers observed in more primitive theropods. Overall, the new specimen brings a new level of detail to our understanding of the anatomy of the juvenile stages of the most species-rich clade of pre-modern birds and contributes to mounting data that enantiornithine development drastically differed from that of Neornithes. 相似文献
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17.
The Family Afrograptidae is a ‘conchostracan’ group with multiple radial costae reaching to the umbo on their carapaces. It comprises four described genera: Afrograpta, Camerunograpta, Congestheriella and Graptoestheriella with a total of thirteen described species which are occasionally reported from the Jurassic and the Cretaceous in Africa, Europe and South America (i.e. Afrograpta from the Upper Cretaceous of Cameroon; Camerunograpta from the Jurassic to Cretaceous of Cameroon; Congestheriella from the Jurassic to Upper Cretaceous of the Congo Basin, Brazil, Bulgaria, Venezuela and Argentina; and Graptoestheriella from the Upper Jurassic to Lower Cretaceous of Brazil). A new genus and a new species, Surreyestheria ockleyensis gen. et sp. nov., belonging to the Family Afrograptidae from the Lower Cretaceous (lower Barremian) Upper Weald Clay Formation of Ockley Village, Surrey County, southern England is described in this paper. The new genus mainly differs from the other four genera by the special reticulate ornamentation on its carapace. It indicates that the Family Afrograptidae was more diverse and more widely distributed in the late Mesozoic than previously supposed. Afrograptidae is a special branch of Estheriellina the latter originating in the late Palaeozoic and the former in the early Mesozoic. Afrograptids, as a whole had been widespread across Pangea in the Early Jurassic. 相似文献
18.
A new soft-shelled turtle (“Trionyx” jixiensis sp. nov.) from the Lower Cretaceous Chengzihe Formation, Jixi city, Heilongjiang Province, China is described on the basis of a nearly complete carapace. The new species is diagnosed by the absence of suprascapular fontanelles and absence of a preneural; eight neurals, tetragonal fifth neural; and eight pairs of costals, with the large eighth costals meeting after the eighth neural. Due to the incompleteness of the specimen and confused classification of the genera of trionychids, the new species cannot be included in any genus of Trionychinae and is temporarily assigned to “Trionyx” (sensu lato). “Trionyx” jixiensis is one of the earliest trionychids, its discovery indicates that the family was already diversified during the Early Cretaceous in Asia. 相似文献
19.
The diversity of serphitid wasps (Proctotrupomorpha: Serphitoidea) in Early Cretaceous (Albian) amber from Spain is described. Four new species have been found representing the genera Serphites Brues 1937, Aposerphites Kozlov and Rasnitsyn 1979, and Microserphites Kozlov and Rasnitsyn 1979. From the Peñacerrada I (Moraza) outcrop two species are described as Aposerphites angustus Ortega-Blanco, Delclòs, Peñalver and Engel, new species and Serphites lamiak, new species. A single species was found at the San Just (Teruel) outcrop and is described as S. silban, new species. Another single specimen was found in El Soplao (Cantabria) outcrop, described as Microserphites soplaensis, new species. This last specimen is especially interesting in sharing typical serphitid and mymarommatoid characters, giving additional support to the apparent close relationship of both groups. 相似文献