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1.
BLACKWELL  W. H. 《Annals of botany》1984,53(1):133-136
Petrified wood from the Lower Upper Cretaceous of north-easternMississippi (Eutaw Formation) in thin-section is most similarto extant Pinus woods of section Pinus, subsection Ponderosae.However, several features also suggest woods of subsection Australes.Based on anatomical detail, geologic age and geographic position,this fossil may represent an ancestral connection between thetwo subsections. Pinuxylon eutawense, silicified wood, Cretaceous, Mississippi, Pinus ponderosa, Pinus taeda  相似文献   

2.
A fossil trimerous flower from the Turonian (ca. 90 MYBP, Upper Cretaceous) of New Jersey is described as a new genus in the familyLauraceae. The fossil flower is charcoalified and preserved in exceptional detail. This fossil specimen is particularly remarkable in that several pollen grains have been preserved; pollen grains ofLauraceae generally have very thin exine and are rarely preserved in the fossil record. Although the specimen is incomplete and lacks anthers, there are sufficient structural details preserved to permit an assignment to theLauraceae, as well as comparisons with the tribePerseeae. This new genus provides an important addition to our knowledge of systematic and structural diversity in CretaceousLauraceae.  相似文献   

3.
Robert Metz 《Ichnos》2013,20(4):190-193
Offshore marine deposits of hemipelagic dark-gray shales comprising the Middle Devonian Mahantango Formation have yielded the first evidence of the trace fossil Paleodictyon from Pennsylvania. Paleodictyon occurs in conjunction with a diversity of largely deposit-feeding trace fossils belonging to the Cruziana ichnofacies, and documents another example of a shallower-water occurrence of this ichnofossil in Paleozoic rocks.  相似文献   

4.
Fossil pollen and macrofossils of Epacridaceae are uncommonand are mainly known from Tasmania and other parts of south-easternAustralia. Most epacrids have generalized ericalean pollen althoughthe pollen of some genera is distinctive. Ericalean pollen isknown from the late Cretaceous. The first occurrence ofParipollisorchesis pollen, which is consistent with some extantEpacrisspecies,probably means that Epacridaceae, and possibly the tribe Epacrideae,had differentiated by the Middle Eocene. The fossil record at present provides minimum ages of the firstoccurrences of major subfamilial taxa. Macrofossils of subfamilyRicheoideae and of several morphotypes of the tribe Epacrideaeare known from the Early Oligocene. Tribe Cosmelieae pollenand macrofossils are known from the Early Pleistocene, and areprobablySprengelia. The oldest Australasian fossils of tribeStyphelieae are leaves in latest Oligocene–Early Mioceneparts of the Latrobe Valley coal. Endocarps identified as Epacridaceaefrom the Eocene of England need further investigation. PollenofMonotoca, or a close relative, is known from the mid-Miocene.PossibleTrochocarpaleaves occur in Late Oligocene/Early Miocenesediments, and fossil leaves indistinguishable from the extantTasmanian rainforest species,T. gunniiandT. cunninghamii, areknown from the Early Pleistocene in Tasmania. Epacridaceae; macrofossils; microfossils; Cretaceous; Cainozoic  相似文献   

5.
A new trace fossil, Foersterichnus rossensis igen. nov. and isp. nov., is described from the Coniacian Hidden Lake Formation, James Ross Island, Antarctica. The trace fossil is a trackway comprising straight, or slightly curving, paired rows of elongate to tear-shaped impressions, parallel or slightly inclined to the long axis of the trackway. Foersterichnus is interpreted to be the trackway of a brachyuran decapod crustacean. It occurs in transgressive shallow marine deposits formed above the storm wave base in a shelf setting. Preservation of the trackway may have been linked to a rapid deoxygenation event during drowning that led to cessation of bioturbation allowing preservation of mixed layer trackways.  相似文献   

6.
Silicified fossil woods from the Late Cretaceous (Santonian) Aachen Formation of northeast Belgium, southernmost Netherlands and adjacent Germany were investigated. Gymnosperms dominate this assemblage: Taxodioxylon gypsaceum, T. cf. gypsaceum, T. cf. albertense (all Taxodiaceae), Dammaroxylon aachenense sp. nov. (Araucariaceae), Pinuxylon sp. (Pinaceae), and Scalaroxylon sp. (Cycad or Cycadeoid). Angiosperms are minor constituents: Nyssoxylon sp. (Nyssaceae?, Cornaceae?), Mastixioxylon symplocoides sp. nov. (Mastixiaceae?, Symplocaceae?), Plataninium decipiens (Platanaceae) and Paraphyllanthoxylon cf. marylandense (Anacardiaceae?, Burseraceae?, Lauraceae?).The composition of this assemblage and the anatomy of the woods indicate a seasonal and humid warm-temperate to subtropical climate.  相似文献   

7.
Finds of fossil wood with bivalve wood borings (Teredolites clavatus and T. longissimus) occur in various facies and presumed sedimentary settings of the platform, shallow-marine Bohemian Crectaceous Basin. The basin comprises areas with sandy-dominated sediments, with marl and clay-dominated sediments, areas with predominat sandy-marly rocks, and finally areas dominated by calcareous nearshore sediments. Teredolites clavatus is common in fossil wood of sandstones, originating in beach or deltaic settings; marl and clay-dominated rock frequently bear wood fragments densely bored by Teredolites longissimus. When accompanied by evidence of marine environments as body fossils, glauconite or typical trace fossils, most of the wood fragments are bored. The presence/absence of borings in wood fragments can be considered the most reliable and easily useable criterion of distinction of marine settings in sandy sediments of the margin of the Bohemian Cretaceous Basin.  相似文献   

8.
3rd ed. By Clark Spencer Larsen, Robert H. Matter, and Daniel L. Gebo. Prospect Heights, IL: Waveland Press. 1998. 225 pp. ISBN 1-57766-002-1. $18.95 (paper).  相似文献   

9.
Lauranthus futabensis , gen. et sp. nov. is assigned to the Lauraceae based on the regular trimerous organization of the perianth and androecium, and the valvate anthers. It provides the first detailed report of lauraceous flowers from the Cretaceous of Asia and adds significantly to our knowledge of the geographic distribution of Cretaceous Lauraceae and their systematic and structural diversity. Received 11 April 2001/ Accepted in revised form 30 August 2001  相似文献   

10.
Entomological Review - The paper overviews the fossil record of insects with long mouthparts and rostra adapted to feeding on floral nectar and pollination drops of extinct gymnosperms. The...  相似文献   

11.
The Fossil Record of Feather Evolution in the Mesozoic   总被引:1,自引:1,他引:0  
The oldest known feathers from the Late Jurassic are alreadymodern in form and microscopic detail. Because these oldestexamples are assignable to an extinct branch (Sauriurae) ofthe basal avian dichotomy, their features must have been establishedat a significantly earlier date. The skin of a wide varietyof dinosaurs is now known and is unlikely to represent a predecessorto a feather bearing integument. Examples of feathered dinosaursresult from erroneous identification of internal structuresas part of the skin covering, and from the confusion of flightlessbirds from the Early Cretaceous of China with dinosaurs.  相似文献   

12.
张武  郑少林 《Acta Botanica Sinica》1999,41(12):1312-1316
报道了辽宁早白垩世化石木的一个新属—原始金松型木 (Protosciadopityoxylongen .nov .)。该属化石以辽宁原始金松型木 (Protosciadopityoxylonliaoningensegen .etsp .nov .)为代表。文中对新属新种进行了描述 ;讨论了新属与现存金松属 (Sciadopitys)及化石金松型木属 (Sciadopityoxylon)的关系 ;并与其相似的原始叶枝杉型木属 (Protophyl locladoxylon)、原始圆孔木属 (Protocircoporoxylon)及异木属 (Xenoxylon)作了比较。  相似文献   

13.
A new genus ( Protosciadopityoxylon gen nov. ) of Early Cretaceous fossil wood reported in the present paper was discovered from Liaoning Province, China, and is named as a new species:Protosciadopityoxylon liaoningense gen. et sp. nov. It is described here and this generic name, adopted by the authors, is employed for fossil wood that is believed to be nearly related to the recent genus Sciadopitys and the fossil genus Sciadopityoxylon. The new genus bears some similarities to Protophyllocladoxylon,Protocircoporoxylon and Xenoxylon in different geological ages, but it differs from them in the types of cross-field pitting.  相似文献   

14.
A skeleton of a ghost pipefish (Solenostomidae) from the Pshekha Subformation of the Khadum Formation (Lower Oligocene) in the Republic of Adygea was discovered. This is the first fossil record of Solenostomidae in Russia; moreover, it is the only ghost pipefish found in the Oligocene. To date, only two fossil solenostomid genera and species from the Eocene of Monte Bolca (Italy) have been recorded. The only Recent genus of this family, Solenostomus Lacepède, 1903, contains four species. The new specimen is incompletely preserved; it lacks a fragment of the body and some fins, precluding the establishment of genus and species of this form. However, the unique geographical position and age of the new fossil expand our knowledge of the evolution and geographical range of the family Solenostomidae.  相似文献   

15.
The fossil record of vertebrate tracks in Mexico is taxonomically rich and geographically diverse, and ranges in age from Middle Jurassic to Pleistocene and possibly Holocene. Middle Jurassic saurischian dinosaur tracks from Oaxaca represent the oldest record of vertebrate tracks in Mexico. Tracks attributed to Late Jurassic theropods and ornithopods are known from Michoacán. Theropod tracks of supposed Jurassic age are known from Durango. Lower Cretaceous Saurischian and ornithopod tracks are known from southern Puebla. Central Mexico has yielded Late Cretaceous hadrosaurid and sauropod tracks (Puebla), and tracks belonging to Theropoda and Ornithopoda (El Aguaje, Michoacan). In Coahuila several tracksites occur within the Cerro del Pueblo Formation and include tracks of mesoreptiles, pterosaurs, small to large theropods, bipedal and quadrupedal ornithopods, birds and possibly a mammal. A tracksite in the Olmos Formation includes tracks of turtles, crocodilians, medium-sized theropods, small ornithopods, and birds. Bird tracks of supposed Eocene age are known from Sinaloa. Two important Pleistocene ichnofaunas occur in the states of Puebla (Tepexi de Rodríguez) and Jalisco (San Juan de los Lagos), and include tracks of camelids, artiodactyls, small ungulates, elephants, large felids and birds. Pleistocene human tracks occur in Coahuila and Jalisco. Mexico's track record provides important insights into vertebrate diversity, paleoecology, and paleoenvironments. Given the rate of new discoveries since 1998, there is no doubt that new sites await to be found.  相似文献   

16.
17.
The predatory boring habit common to many recent snails probablyarose first in the Polinicinae (Naticacea) during Upper Cretaceous(Cenomanian) times (100 million years B.P.) . In the fossilrecord the frequency of bored shells increasesgreatly in rocksof latest Cretaceous age and becomes more widespread duringearly Tertiary times coincident with the major diversificationof the primary groups of boring snails. The borings in these Cretaceous and Tertiary shells show thesame characteristics of preference of penetration in one pelecypodvalve rather than the other or in position of the boring siteon the shell that are found in recent shell assemblages. Borings in Paleozoic brachiopod shells (230–550 millionyears old) that have previously been attributed to gastropodpredation are herein attributed to other but unknown boringorganisms. In part these borings are not accepted as evidence of Paleozoicgastropod predation because it necessitates: (1) Postulationof the separate development of a boring habit ith its concomitantdevelopment of an accessory boring organ in a groupwhose descendantsare all herbivores, and (2) The development of such a habithundreds of millions of years before the appearance of any relativesof present day borers.  相似文献   

18.
Summary New petrographic and isotopic data from inoceramid bivalve shells and belemnite rostra from the lower Campanian and belemnite rostra from the mid-upper Maastrichtian of the Marambio Group, James Ross Basin, Antarctica are presented. Most of the inoceramid data were processed from shell fragments of the large formAntarcticeramus rabotensis (Crame and Luther) at the stratigraphic level marking the extinction of the inoceramids in the James Ross Basin (uppermost early Campanian-basal late Campanian). Standard transmitted light microscopy and cathodoluminescence (CL) studies in thin sections ofA. rabotensis show clear evidence of environmental stress, which is reflected as marked growth breaks in the shell banding of this large inoceramid bivalve. At Redonda Point, CL and the mean oxygen isotopic value (δ18O=-3.11‰ 3 (PDB); n=11; t°=25.4°C) indicate a varied degree of diagenetic modification, but without any evidence of neomorphism along the prismatic microstructures. Early Campanian belemnite rostra are much less diagenetically modified (at the Brandy Bay section; and the Santa Marta section; δ18O=-0.50‰ (PDB); n=5; t°=14.0°C and 3 δ18O=-0.94‰ (PDB); n=21; t°=15.8°C) and are non luminescent 3 except for localized, organic-rich bands. The mean oxygen isotopic value for mid-late Maastrichtian belemnite rostra (at the Seymour Island section; δ18O=-0.11‰ 3 (PDB); n=5; t°=12.5°C) indicates a substantial drop in the sea-water paleotemperature, suggesting a causal relationship between the early extinction of the inoceramid bivalves in high latitudes of the Southern Hemisphere and the falling sea-water temperature.  相似文献   

19.

Background

We describe the first occurrence in the fossil record of an aquatic avian twig-nest with five eggs in situ (Early Miocene Tudela Formation, Ebro Basin, Spain). Extensive outcrops of this formation reveal autochthonous avian osteological and oological fossils that represent a single taxon identified as a basal phoenicopterid. Although the eggshell structure is definitively phoenicopterid, the characteristics of both the nest and the eggs are similar to those of modern grebes. These observations allow us to address the origin of the disparities between the sister taxa Podicipedidae and Phoenicopteridae crown clades, and traces the evolution of the nesting and reproductive environments for phoenicopteriforms.

Methodology/Principal Findings

Multi-disciplinary analyses performed on fossilized vegetation and eggshells from the eggs in the nest and its embedding sediments indicate that this new phoenicopterid thrived under a semi-arid climate in an oligohaline (seasonally mesohaline) shallow endorheic lacustine environment. High-end microcharacterizations including SEM, TEM, and EBSD techniques were pivotal to identifying these phoenicopterid eggshells. Anatomical comparisons of the fossil bones with those of Phoenicopteriformes and Podicipediformes crown clades and extinct palaelodids confirm that this avian fossil assemblage belongs to a new and basal phoenicopterid.

Conclusions/Significance

Although the Podicipediformes-Phoenicopteriformes sister group relationship is now well supported, flamingos and grebes exhibit feeding, reproductive, and nesting strategies that diverge significantly. Our multi-disciplinary study is the first to reveal that the phoenicopteriform reproductive behaviour, nesting ecology and nest characteristics derived from grebe-like type strategies to reach the extremely specialized conditions observed in modern flamingo crown groups. Furthermore, our study enables us to map ecological and reproductive characters on the Phoenicopteriformes evolutionary lineage. Our results demonstrate that the nesting paleoenvironments of flamingos were closely linked to the unique ecology of this locality, which is a direct result of special climatic (high evaporitic regime) and geological (fault system) conditions.  相似文献   

20.
Soft tissue preservation is reported from Upper Devonian deposits of the Holy Cross Mountains, central Poland, for the first time. The preserved soft tissues are muscles associated with arthropod cuticle fragments. The muscles are phosphatized with variable states of preservation. Well-preserved specimens display the typical banding of striated muscles. Other muscle fragments are highly degraded and/or recrystallized such that their microstructure is barely visible. The phosphatized muscles and associated cuticle are fragmented, occur in patches and some are scattered on the bedding plane. Due to the state of preservation and the lack of diagnostic features, the cuticle identification is problematic; however, it may have belonged to a phyllocarid crustacean. Taphonomic features of the remains indicate that they do not represent fossilized fecal matter (coprolite) but may represent a regurgitate, but the hypothesis is difficult to test. Most probably they represent the leftover remains after arthropod or fish scavenging. The present study shows that soft tissues, which even earlier were manipulated by scavenger, may be preserved if only special microenvironmental conditions within and around the animal remains are established.  相似文献   

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