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1.
Abstract: We describe a new, exceptionally well‐preserved fossil bird recovered from marine deposits of the Early Eocene Fur Formation of Denmark. Morsoravis sedilis gen. et sp. nov. is known by a single specimen that consists of a three‐dimensional skull, vertebral column, ribs, pelvis, and left hindlimb and associated parts of the right hindlimb. Comparisons based on overall morphology and particularly characters of the skull, vertebrae and pelvis indicate that the new specimen is morphologically similar to charadriiform birds (the shorebirds and relatives). This similarity is also expressed by a phylogenetic analysis of higher neornithine (modern birds) taxa, which supports a close relationship between the new fossil and modern charadriiforms. The morphology of the hindlimbs, in particular, shows that the new fossil corresponds to a new taxon that is distinguishable from modern charadriiform clades. One interesting aspect of its morphology is the presence of hindlimb specializations that are most commonly found among perching birds – these suggest that ecologically the new Danish fossil bird may have differed from the wading habits typical of most charadriiforms.  相似文献   

2.
GERALD MAYR  & CHARLES W. KNOPF 《Ibis》2007,149(4):774-782
A new species of the charadriiform taxon Turnipax Mayr, 2000 is described from the Lower Oligocene fossil site Frauenweiler in southern Germany. The postcranial skeleton assigned to Turnipax oechslerorum sp. nov. is very well preserved and allows the recognition of significant, previously unknown osteological details of Turnipax , especially concerning the wing and pectoral girdle bones. We provide evidence that Turnipax is a stem lineage representative of the Turnicidae (buttonquails) and synonymize Turnipacidae Mayr, 2000 with Turnicidae Gray, 1840. Turnipax is the earliest fossil representative of the Turnicidae, which otherwise have no Paleogene fossil record. Because recent molecular studies support a charadriiform origin of buttonquails, the mosaic distribution in the skeleton of Turnipax of derived features of the Turnicidae and non-turnicid charadriiform birds is of particular interest. Turnipax exhibits a more plesiomorphic morphology than extant Turnicidae, and we assume that its habitat and way of living differed from that of crown group Turnicidae, which may not have diversified before the spread of grasslands during the Oligocene and Miocene.  相似文献   

3.
The early Tertiary (Paleocene and Eocene) family Presbyornithidae is one of the most completely known group of fossil birds. Essentially all parts of the skeleton are represented in the fossil record, allowing a thorough analysis of the phylogenetic position of the family. Forty-two families of nonpasserine birds representing the orders Ciconiiformes, Anseriformes, Galliformes, Gruiformes and Charadriiformes, were included in a cladistic analysis of 71 skeletal characters. The previously suggested anseriform affinity of the Presbyornithidae was confirmed. Furthermore, the family proved to be closer to the Anatidae than to the Anhimidae or Anseranatidae. The many postcranial similarities with certain charadriiform birds as the Burhinidae, obviously are plesiomorphies. By this observation, a better undestanding of character evolution in nonpasserine skeletal morphology is gained. The often suggested close relationship of anseriform and galliform birds is not confirmed by osteology. Instead, the Anseriformes and the Phoenicopteridae form a monophyletic clade that is the sister to the remaining ciconiiform birds. This result renders the Ciconiiformes sensu Wetmore (1960) polyphyletic.  相似文献   

4.
辽宁早白垩世早期—鸟化石   总被引:3,自引:1,他引:2  
本文记述了发现于辽宁朝阳地区早白垩世早期一新的鸟类。这是继三塔中国鸟(Sinornis santensis)、燕都华夏鸟(Cathayomis yandica)之后报道的辽宁中生代第三种鸟化石,它的脊柱和腰带与始祖鸟和恐龙相似,但其肋骨又具有现代鸟类的性状,这是早期鸟类化石的又一新材料。  相似文献   

5.
湖北松滋早始新世一鸟化石   总被引:3,自引:2,他引:1  
侯连海 《古脊椎动物学报》1990,28(1):34-42,T001,T002
本文记述了采自湖北松滋县王家桥区黑档口早始新世洋溪组页岩中一保存较好的鸟化石。依其形态特征归于鹤形目内,但它与已知鹤形目各科又有某些明显的区别,与秧鸡科比较接近。建立一新科:松滋鸟科Songzidae fam. nov.代表我国已知鹤形目化石最早的记录。这一发现还证明始新世早期亚洲东部北纬30°左右已有比较原始的小型鹤形目鸟类分布。本文还讨论了松滋鸟的某些形态功能。  相似文献   

6.
Gerald Mayr 《Ibis》2015,157(1):54-67
A partial skeleton of the early Eocene tropicbird Prophaethon shrubsolei (Prophaethontidae) from the London Clay of Walton‐on‐the‐Naze (UK) is described. Most of the bones preserved in this fossil have not been described previously for Prophaethon or prophaethontids in general. The pelvis and leg bones of Prophaethon, including the previously unknown tarsometatarsus, are very different from modern tropicbirds and show a strong similarity to procellariiform birds, especially albatrosses. Rather than employing plunge‐diving like their extant relatives, prophaethontids therefore probably used foraging strategies similar to those of modern albatrosses, which seize food on the sea surface. Prophaethontids also appear to have been less pelagic than extant tropicbirds, and these different life modes, as well as the disappearance of Phaethontiformes from northern latitudes, attest to major changes in Northern Hemispheric marine avifaunas during the Cenozoic, which also affected other pelagic birds. The reasons for the profound changes in the historical biogeography and way of living of tropicbirds are unknown, but ecological competition and predation at breeding sites are likely to have played a role.  相似文献   

7.
Abstract: A new, unusually well‐preserved juvenile specimen of Ctenochelys stenoporus from the Niobrara Formation is described. The skull has come apart at its sutures and all bones of the braincase and ear region are preserved three‐dimensionally. This allows a detailed reconstruction of the important brain structures of a basal juvenile cheloniid turtle. It is compared with adult Ctenochelys specimens, and the major ontogenetic changes in the skull and postcranial skeleton are described. Furthermore, the specimen is compared with other fossil and extant cheloniids with well‐known braincases and the differences between basal and advanced cheloniids turtles are specified.  相似文献   

8.
An incomplete ‘mummy’ from the Phosphorites du Quercy (presumed Eocene) was identified as a salamander during the 19th century. The specimen has now been computed tomography (CT) scanned, and this revealed the incomplete skeleton (with perfectly preserved bones) and soft tissues (lung). The fossil represents a new, well‐characterized taxon. Despite the absence of the skull, several features allow a phylogenetic analysis. The fossil belongs to pseudosaurian caudates; it is tentatively assigned to the Salamandridae, although affinities with Plethodontidae cannot be definitely ruled out.  相似文献   

9.
Two new specimens of the oviraptorid theropod Nemegtomaia barsboldi from the Nemegt Basin of southern Mongolia are described. Specimen MPC-D 107/15 was collected from the upper beds of the Baruungoyot Formation (Campanian-Maastrichtian), and is a nest of eggs with the skeleton of the assumed parent of Nemegtomaia on top in brooding position. Much of the skeleton was damaged by colonies of dermestid coleopterans prior to its complete burial. However, diagnostic characters are recovered from the parts preserved, including the skull, partial forelimbs (including the left hand), legs, and distal portions of both feet. Nemegtomaia represents the fourth known genus of oviraptorid for which individuals have been found on nests of eggs. The second new specimen, MPC-D 107/16, was collected a few kilometers to the east in basal deposits of the Nemegt Formation, and includes both hands and femora of a smaller Nemegtomaia individual. The two formations and their diverse fossil assemblages have been considered to represent sequential time periods and different environments, but data presented here indicate partial overlap across the Baruungoyot-Nemegt transition. All other known oviraptorids from Mongolia and China are known exclusively from xeric or semi-arid environments. However, this study documents that Nemegtomaia is found in both arid/aeolian (Baruungoyot Formation) and more humid/fluvial (Nemegt Formation) facies.  相似文献   

10.
《Annales de Paléontologie》2017,103(2):141-147
A small bird with a shorebird-like beak and a very long hind toe is described from the Early Eocene of Messel in Germany. Vanolimicola longihallucis, gen. et sp. nov. is one of the few candidate species for a “wading bird” from Messel, that is, a bird that may have foraged along the shoreline of the ancient lake. A few features indicate a relationship to charadriiform birds and Jacanidae (jacanas) in particular, but charadriiform affinities are only weakly supported. In the preserved skeletal elements, V. longihallucis also resembles the taxon Songzia from the Early Eocene of China, which is considered to be a representative of the Ralloidea (rails and allies). A potential biogeographic significance of the new Messel fossil is strengthened by similar fossils from the North American Green River Formation.  相似文献   

11.
Two pelvises from a similar archaeological context have been discovered in recent years in two different caves in Israel. The pelvis from the Qafzeh cave (Qafzeh 9) was dated by means of thermoluminescence at approximately 95 kyr BP. All available measurement values, the most significant being those of the diagnostic obturator region, fall within those of the modern range. The other pelvis emanates from the Kebara cave and differs fundamentally from modern pelvises and from the Qafzeh specimen, although the Kebara pelvis is 30,000 years younger than the latter. As in other remains of Neandertal pelvises, the superior pubic ramus of the Kebara hominid is extremely long and slender and exhibits a cross section unlike that of modern humans. The absolute height of the obturator region is very small. It is these measurements and proportions that set the Kebara pelvis apart from both modern pelvises and the specimen from Qafzeh. The morphological differences and the chronological relationship between the two fossil pelvises support the concept of two distinct evolutionary lineages for these hominids.  相似文献   

12.
Two new specimens of the fossil stem group galliform Paraortygoides messelensis Mayr 2000 (Gallinuloididae) are described from the Middle Eocene of Messel in Germany, including a complete skeleton in which the hitherto unknown skull of this species is preserved. The shorter and more protruding crista deltopectoralis of the humerus, also for the first time visible in one of the new specimens, shows gallinuloidids to be the sister taxon of all other, extinct and extant, galliform birds. Gallinuloidids distinctly differ from modern Galliformes in several other plesiomorphic osteological features, mainly of the pectoral girdle, of which the absence of a spina interna on the sternum is here reported for the first time. It is assumed that major evolutionary transformations in the stem lineage of Galliformes are related to the evolution of a large crop, which appears to have been absent in gallinuloidids. The vegetarian food component of gallinuloidids thus probably mainly consisted of soft plant matter rather than coarse material such as seeds.  相似文献   

13.
We describe an enormous Late Cretaceous fossil bird from Kazakhstan, known from a pair of edentulous mandibular rami (greater than 275 mm long), which adds significantly to our knowledge of Mesozoic avian morphological and ecological diversity. A suite of autapomorphies lead us to recognize the specimen as a new taxon. Phylogenetic analysis resolves this giant bird deep within Aves as a basal member of Ornithuromorpha. This Kazakh fossil demonstrates that large body size evolved at least once outside modern birds (Neornithes) and reveals hitherto unexpected trophic diversity within Cretaceous Aves.  相似文献   

14.
Gerald Mayr 《Ibis》2013,155(2):384-396
A new fossil stem group representative of Coliiformes (mousebirds) with a remarkable skull morphology is described from the late Oligocene of Germany. Oligocolius psittacocephalon sp. nov. for the first time preserves the skull of a post‐Eocene fossil mousebird. This exhibits a combination of skull features unknown from any other bird and converges on the skull of parrots in that the beak is separated from the cranium by a marked nasofrontal hinge and in that the interorbital part of the frontal bones is very wide. In addition, the mandible of the new species exhibits long retroarticular processes, which are unexpected because unlike in other coliiform birds exhibiting this feature, the short beak was probably not used for probing in substrate. It is hypothesized that the retroarticular processes of O. psittacocephalon instead served for a particular wide and forceful opening of the beak. Eight large fruit stones are situated in the area of the digestive tract of the new species. Preservation of most of these in a well‐delimited cluster in the region of the upper oesophagus suggests that, unlike in modern mousebirds, O. psittacocephalon had a crop. The new fossil shows that late Oligocene European stem group Coliiformes significantly differed from their extant relatives in morphology and probably also in feeding ecology.  相似文献   

15.
A new genus and species of otter‐like mustelid, Teruelictis riparius, is created on the basis of a partial skeleton from the Late Miocene (Vallesian age, MN 10) locality of La Roma 2 (Teruel, Spain), including several postcranial elements, the skull, and the mandible. The combination of a typically lutrine dentition, similar to that of other fossil otters such as Paralutra jaegeri, with a very slender postcranial skeleton, including a long back and gracile long bones and metacarpals, thus lacking any aquatic adaptations, was previously unknown in the fossil record. This mosaic of features strongly suggests the possibility that the aquatic lifestyle of otters could have appeared after the initial development of the distinctive dental morphology of this specialized group of mustelids. © 2013 The Linnean Society of London  相似文献   

16.
17.
根据发现于辽宁西部建昌早白垩世九佛堂组一件保存较为完好的标本,描述了原始今鸟类一新属种,李氏叉尾鸟(Schizooura lii gen.et sp.nov.)。系统发育分析表明,它较建昌鸟和古喙鸟进步,但又较热河生物群中其他已知的今鸟类原始。这一新种叉骨呈Ⅴ型,且具有一短的叉骨突,这是这一特征首次在早白垩世今鸟中发现。其胸骨加长,后缘无窗孔,且无很深的凹口。肱骨三角肌脊膨大,近乎达到肱骨长的一半。新鸟的头骨保存较好,显示其具喙的特征,前颌骨直接与额骨相关节。值得关注的是,这件标本首次展示了在中生代鸟类中,除扇形尾羽之外的第二种尾羽类型。新标本具叉形尾羽,中间分隔明显。对现生鸟类的研究表明,叉尾型的空气动力学效率比扇尾型要低,但在性选择方面具有优势。这一新的发现说明,在热河生物群生活的森林环境中,今鸟类的基干种类在尾羽性状上或许已经存在着不同的选择策略。  相似文献   

18.
A new genus and species of catshark (Neoselachii, Carcharhiniformes, Scyliorhinidae) —Bavariscyllium tischlingeri n. gen. n. sp. — is described from the Late Jurassic (Tithonian) Plattenkalke of South Germany. The new taxon is known from a single articulated skeleton having the skull, the trunk and all of the fins preserved. The position of the first dorsal fin in relation to the pelvic fins and the dental morphology shows that the specimen belongs into the neoselachian family Scyliorhinidae. Two isolated tooth crowns from the Kimmeridgian of North Germany are identified asBavariscyllium sp. and represent the oldest unambigious fossil record of the Scyliorhinidae known so far.  相似文献   

19.
山东临朐的鸟化石   总被引:4,自引:1,他引:4  
本文记述了产自山东临朐解家河硅藻土矿(中新世中期)中的两件鸟类化石。一件保存完整,鉴定为雁形目鸭科的新属种——硅藻中华河鸭,其特征与河鸭属最为近似。这是我国雁形目中迄今所知保存最完整的化石记录,也是该目中我国已知的最早代表。另一件只部分保存,骨骼均甚粗大。从完整的后肢骨骼特征看,应属鸡形目中的大型鸟类,归雉科,名为硕大临朐鸟,新属,新种。  相似文献   

20.
Recent survey of the fossiliferous variegated mudstones of the PK1 locality (Sabapondaung) in the late middle Eocene Pondaung Formation (central Myanmar) has led to the recovery of a partial right innominate of a relatively large-bodied primate. Given its size and provenance, this bone probably belongs to the same individual represented by the NMMP 20 primate partial skeleton described previously from the same locality. The new fossil, which preserves the region around the acetabulum and the adjacent part of the ilium, clearly exhibits strepsirrhine rather than anthropoid affinities. This addition to our knowledge of the NMMP 20 partial skeleton allows us to reassess the different locomotor interpretations that have been proposed for this specimen. Aspects of pelvic morphology suggest that the NMMP 20 partial skeleton documents a primate that probably engaged in active arboreal quadrupedalism similar to that practiced by medium-sized Malagasy lemurids rather than lorislike slow moving and climbing. Given the conflicting phylogenetic signals provided by NMMP 39 (a talus showing anthropoid affinities) and NMMP 20 (a partial skeleton bearing adapiform affinities), it appears that two higher-level taxonomic groups of relatively large-bodied primates are documented in the Pondaung Formation. The recent discovery of two taxa of sivaladapid adapiforms from the Pondaung Formation indicates that the assumption that the NMMP 20 partial skeleton belongs to an amphipithecid can no longer be sustained. Instead, this specimen apparently documents a third large-bodied sivaladapid species in the Pondaung Formation.  相似文献   

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