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1.
The first fossil record of the genus Nageia Gaertner from the Tertiary of southern China is reported. Nageia hainanensis sp. nov. is described from the Eocene Changchang Formation of Hainan Island. The extant species of Nageia are widely distributed in southeastern Asia, from northeastern India to southeastern China and southern Japan, and southward through Indochina to the Malay Archipelago and New Guinea. The fossil evidence of Nageia has been discovered from the Lower Cretaceous of the Far East of Russia and Japan. The distribution of both modern and fossil species of Nageia indicates that this genus could have originated in the northeastern part of Asia in the Early Cretaceous and spread to south China at least in the Eocene. Discovery of Nageia fossil record in south China provides important evidence for the geological and phytogeographic history of the genus.  相似文献   

2.
A new fossil species of crane-fly, Helius botswanensis:Diptera: Tipulidaey is described. The specimen was discovered recently in reliably dated. Cretaceous sediments from Botswana. Ii is extremely well preserved, has a distinctive morphology, and is identified as belonging to the extant genus Helius. The single specimen puts the origin of the subfamily Limoniinae and the genus well into the Cretaceous Period, and provides data on the southern African Cretaceous palaeoenvironment. The conservative nature of a dipteran of such antiquity, assignable to an extant genus which has an association with flowers, has implications for evolutionary theory.  相似文献   

3.
A new species of Late Cretaceous clawed lobster, Paraclytia valashtensis, is described. The discovery is a notable addition to the sparse decapod fossil record of Iran, and this is the first record of the genus outside central Europe. The four previously known species of Paraclytia are from Germany and the Czech Republic, so this discovery represents a significant expansion of the palaeogeographic range of the genus.  相似文献   

4.
Lactoridaceae are a monotypic family confined to Masatierra Island, Juan Fernández Archipelago, in the Pacific Ocean. It grows in the understorey of a subtropical montane rain forest. Lactoridaceae most probably originated in southern South Africa in the Cretaceous, with the oldest records in the Turonian–Campanian, and reached its widest palaeogeographical distribution by the Maastrichtian, extending into Australia, India, Antarctica, and North and South America. In this paper, we report a new fossil find of lactoridaceous tetrads from the early Miocene of eastern Patagonia, southern South America. This record is the youngest and geographically one of the closest to the extant Lactoris distribution area. Patagonian fossil material shows greater similarities to extant L. fernandeziana Phil. than to any other described morphotaxon. The family may have migrated into South America, either via Africa (through the Atlantic Ocean) or Antarctica, by the Maastrichtian, growing in eastern Patagonia up to the early Miocene. Arid conditions established in this region by the middle–late Miocene onwards would have determined the restriction of forests to the western lands. Lactoridaceae may have followed a similar migration pattern towards the Pacific coast of South America. The shifting of Lactoridaceae towards Masatierra Island would have occurred in the last 4 Myr by long‐distance dispersal events (perhaps by birds). © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 41–50.  相似文献   

5.
The family Osmundaceae is among the most primitive ferns of the Filicales, with an extensive fossil record dating back to the Late Paleozoic. Numerous fossil osmundaceous rhizomes have been documented in the geological history. However, the diversity, variation and distribution pattern of permineralized rhizomes remain poorly known. Here we intend to analyze the fossil records with regard to the diversity and distribution pattern of the osmundaceous rhizomes based on available data. To date, about 83 species ascribed to 14 genera of fossil osmundaceous rhizomes have been described worldwide, assigned to two subfamilies, namely, Thamnopteroideae and Osmundoideae. Geologically, two groups (i.e., Thamnopteroideae and Palaeosmunda) have been reported in the Permian. All the Triassic taxa are from the southern hemisphere. Jurassic osmundaceous rhizomes are abundant and widespread throughout the world, most dominant in the southern hemisphere. During the transition of Jurassic to Cretaceous, the diversity of osmundaceous rhizomes declined rapidly. In the Cretaceous, however, the osmundaceous rhizomes from the northern hemisphere surpass those from the southern hemisphere in generic level for the first time. The Cenozoic taxa diversified in the northern hemisphere with the rise of angiosperms. Geographically, the osmundaceous fossil rhizomes have been found in both hemispheres; the major localities include Ural area of the former USSR, Tasmania of Australia, southern Argentina, Antarctica, northern India, central and western part of North America and northern China. We discuss the origin, radiation, and development of the Osmundaceae based on rhizomes, to help further understand the systematic relation and evolutionary history of the family Osmundaceae.  相似文献   

6.
Fossil wood of the Winteraceae from the Upper Cretaceous sedimentsof James Ross Island, Antarctic Peninsula, is described herefor the first time. The specimen is characterized by the absenceof vessels, rays of two distinct sizes and tracheids with one–threerows of circular bordered pits, mainly on the radial walls,grading to horizontally elongate and scalariform. Despite anatomicalconformity to the family Winteraceae, the fossil wood is notidentical to any one extant genus and therefore has been assignedto the fossil organ genus Winteroxylon Gottwald with which thefossil shows greatest similarity. Copyright 2000 Annals of BotanyCompany Antarctica, Cretaceous, angiosperm, wood, anatomy, Winteraceae, Winteroxylon, fossil, palaeoclimate  相似文献   

7.
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   

8.
Aim To evaluate the Gunnerus Ridge land‐bridge hypothesis, which postulates a Late Cretaceous causeway between eastern Antarctica and southern Madagascar allowing the passage of terrestrial vertebrates. Location Eastern Antarctica, southern Indian Ocean, Madagascar. Methods The review involves palaeogeographical modelling, which draws upon geological and geophysical data, bathymetric charts, and plate tectonic reconstructions, and the evaluation of stratigraphically calibrated phylogenetic analyses to document ghost lineages of select taxa. Results The available geological and geophysical evidence indicates that eastern Antarctica’s Gunnerus Ridge and southern Madagascar were separated for the entire Late Cretaceous by a vast marine expanse. In the mid–Late Cretaceous, the gap was probably punctuated by land on two intervening physiographical highs, the northern Madagascar Plateau and Conrad Rise, the latter of which, although probably large, was still separated from Antarctica’s Riiser‐Larsen Peninsula by c. 1600 km. Recent, stratigraphically calibrated phylogenies including large, terrestrial end‐Cretaceous vertebrate taxa of Madagascar and the Indian subcontinent reveal long ghost lineages that extended into the Early Cretaceous. Main conclusions The view that Antarctica and Madagascar were connected by a long causeway between the Gunnerus Ridge and southern Madagascar in the Late Cretaceous, and that terrestrial vertebrates were able to colonize new frontiers using this physiographical feature, is almost certainly incorrect, as was previously demonstrated for the purported causeway between Antarctica and the Indian subcontinent across the Kerguelen Plateau. Connection across mainland Africa to account for the close relationships of several fossil and extant vertebrate taxa of Indo‐Madagascar and South America is another option, although this too lacks credibility. We conclude that (1) throughout the Late Cretaceous there was no intervening, continuous causeway through Antarctica and associated land bridges between South America to the west and Indo‐Madagascar to the east; and (2) mid‐ to large‐sized, obligate terrestrial forms (e.g. abelisauroid theropod and titanosaurian sauropod dinosaurs and notosuchian crocodyliforms) gained broad distribution across Gondwanan land masses prior to fragmentation and were isolated on Indo‐Madagascar before the end of the Early Cretaceous.  相似文献   

9.
The first two fossil species of the canthyloscelid genus Synneuron are described based on compression wings. Synneuron eomontana sp. nov. is described from the Middle Eocene Coal Creek Member of the Kishenehn Formation, in the USA, and Synneuron jelli sp. nov. is described from the Lower Cretaceous Koonwarra Fossil Bed of the Korumburra Group, in Australia. The wings are illustrated and compared to the extant species of the genus, to species of the three other recent genera of Canthyloscelidae and to an anisopodid. A phylogenetic analysis of the relationships between the species of Synneuron was performed. The Eocene fossil S. eomontana appears as sister of the pair of recent Holarctic species of the genus, while the Australian Cretaceous species S. jelli is sister of the clade with the species of Synneuron of the northern hemisphere. The sister group of Synneuron is the canthyloscelid clade (Hyperoscelis + Canthyloscelis), for which a middle Jurassic fossil is known. At the early Cretaceous, Gondwana was already separated from Laurasia and the disjunction between the species of Synneuron in Australia and the northern hemisphere clade of the genus suggest a true pangeic origin for the genus. The biology of the canthyloscelid larvae is shaped by its trophic specialization—xylosaprophagous. This suggests that the transition from the Pangean Jurassic gymnosperm-dominated forests to the late Cretaceous angiosperm-dominated forests may be related to the low recent diversity of Synneuron or of the canthyloscelids in the world—and maybe to the extinction of the genus in the southern hemisphere. This major turnover of the vegetation type along the Cretaceous may be also somehow related to the complete extinction of other groups of flies strictly associated with gymnosperms, as may be the case of the lower brachyceran family Zhangsolvidae. This speculation needs additional corroboration from other groups, that will become available with the combination of systematics, paleontology and biogeographical information of different early Cretaceous clades.  相似文献   

10.
Three new taxa from Albian, Early Cretaceous assemblages in Gondwana (Australia and Antarctica) and two previously described fossils from the Late Cretaceous and Eocene of North America are attributable to the heterosporous semi-aquatic fern family Marsileaceae. They are assigned to Marsileaceaephyllum, a morphotaxon erected here for sterile remains (whole plants, and isolated leaves and leaflets) of Marsileaceae. The Gondwanan taxa, Marsileaceaephyllum lobatum and Marsileaceaephyllum spp. B-C, have either a cruciform leaflet arrangement or dichotomous and anastomosing venation characteristic of modern Marsileaceae. Two previously established taxa, Marsilea johnhallii and Marsilea sp., which represent sterile Marsileaceae, are also transferred to the new genus (now Marsileaceaephyllum johnhallii and Marsileaceaephyllum sp. A, respectively). Examination of all fossil venation patterns reveals four new venation types not present in extant taxa, suggesting that most fossil Marsileaceae (leaves) are distinct from extant genera, and are likely members of extinct lineages. This is further supported by the absence of modern megaspore types in the Early Cretaceous.  相似文献   

11.
Cunoniaceae in the Cretaceous of Europe: Evidence from Fossil Flowers   总被引:1,自引:0,他引:1  
Fossil flowers of the Cunoniaceae from Late Cretaceous sedimentsof southern Sweden are described in detail. The flowers aresmall, bisexual, actinomorphic, tetramerous with broadly attachedvalvate sepals; they have narrowly attached petals; eight stamensin two whorls; a massive, lobed nectary; a semi-inferior, syncarpousgynoecium with axile placentation; numerous ovules; separatestyles; and peltate, probably secretory, trichomes. They sharemany features with extant representatives of both the Cunoniaceaeand Anisophylleaceae. However, the gynoecium structure in particularindicates a closer relationship to the Cunoniaceae. The floralcharacters are not specific for any extant genus of the familyand therefore a new genus and species, Platydiscus peltatusgen. et sp. nov., is formally described. This is the first recordof cunoniaceous floral structures from the Northern Hemisphereand the oldest record of Cunoniaceae flowers worldwide. Copyright2001 Annals of Botany Company Anisophylleaceae, Cunoniaceae, fossil flowers, Late Cretaceous, Oxalidales, Platydiscus peltatus gen. et sp. nov., Santonian-Campanian, southern Sweden  相似文献   

12.
Anacolosidites Cookson & Pike, a fossil pollen genus recorded since the Campanian, is peculiar in its morphology – six‐porate with three apertures on each hemisphere, located away from the equator, and with the distal and proximal apertures positioned over each other. Representatives of this fossil genus are widely considered to represent extant Olacaceae from tribe Anacoloseae. Olacaceae is an exclusively tropical angiosperm family with a pantropical distribution; consequently the fossils are often used to suggest a tropical climate and in addition are frequently used as a stratigraphic marker. Fossil species assigned to Anacolosidites are quite variable and may not all represent Olacaceae, in which case they may not indicate tropical climate.

The present study is a morphological survey of fossil pollen assigned to Anacolosidites; it identifies the published reports of the fossil species that probably represent positive occurrences of Olacaceae pollen in the fossil record. Within Olacaceae, Anacolosidites‐type pollen is usually compared with pollen of genera in tribe Anacoloseae, in particular: Cathedra, Anacolosa and Phanerodiscus, but never with the pollen of Ptychopetalum, a genus from tribe Olaceae with closely similar pollen to the other three genera, but with a reticulate tectum and very small circular apertures located near the equator. Nevertheless, the records of reticulate Anacolosidites species which have been excluded from the emended diagnosis are unlikely to be related to Ptychopetalum. The earliest accepted record of Anacolosidites is from the Late Cretaceous (Maastrichtian) of Germany. However, most Late Cretaceous records, and later Russian and Chinese occurrences referred to Anacolosidites, consist mainly of Normapolles‐type pollen, whereas many of the Cenozoic records assigned to Anacolosidites have a much clearer affinity with the pollen of Anacolosa, Cathedra and Phanerodiscus (tribe Anacoloseae). The newly emended genus Anacolosidites may be used as a stratigraphic marker for tropical or megathermal climatic conditions.  相似文献   

13.
A new genus and species of mites, Protoresinacarus brevipedis gen. n., sp. n. (Acari: Heterostigmata: Pyemotoidea), is described from Early Cretaceous Burmese amber. This represents the first fossil record of a member of the family Resinacaridae. It is represented by 21 phoretic females adjacent to an adult mantidfly (Neuroptera: Mantispidae). This is the first record of phoresy of pyemotid mites on members of the insect order Neuroptera. The fossil mites differ from extant members of the family in possessing distinctly shorter legs I, which do not reach beyond the apex of the gnathosoma, and by the long setae v 1, v 2 and c 2.  相似文献   

14.
A phylogenetic analysis of all 17 extant species of the clawed lobster genus Metanephrops based on mitochondrial 12S rRNA, 16S rRNA and cytochrome c oxidase I, and nuclear histone H3 gene sequences supports the morphological groupings of two of the traditional groups of the genus (the binghami and japonicus groups) but refutes monophyly of the other two groups (the arafurensis and thomsoni groups). The results in general support a recent morphology-based cladistic analysis of this genus except that this study suggests M. neptunus to be a basal rather than a derived species as indicated in the morphological analysis. This species is genetically diverse over its geographical range. Moreover, the two color forms of M. thomsoni are genetically distinct, most likely representing different species. The molecular phylogeny and current distribution pattern of the extant species, together with the fossil record, suggest that the genus originated in the Antarctica in the Cretaceous, followed by diversification and dispersal along the continental shelf of different continents as a result of the vicariant events associated with the breakup of the Southern Temperate Gondwana since Late Cretaceous.  相似文献   

15.
A survey of Cycadalean taxa of Argentina (including Antarctica) is presented. The record of leaves represented byNilssonia, Pseudoctenis, Ctenis, Mesodescolea, Ticoa, Almargemia,Kurtziana, andZamia genera are summarized. Recent investigations made of cuticles with transmission and scanning electron microscopy are included. In stems, a preliminary study of two forms found in the Upper Cretaceous of Rio Negro Province are incorporated intoMichelilloa, Bororoa, andMenucoa. The fossil record shows some characters of leaf morphology, presence of inverse xylem and medullary bundles, two kinds of leaf traces, and monoxylic and polyxylic steles of systematic importance when compared with both extant and fossil cycads. Affinities of fossil taxa related to extant families are suggested through analysis of the above-mentioned characters. The presence of medullary vascular rings related to the emission of terminal reproductive strobili are recognized inBororoa andMenucoa. This character associated with polyxyly makes it possible to assign these genera to the Zamiaceae-Encephalartoideae sensu Stevenson, widening the paleogeographical distribution of this subfamily.  相似文献   

16.
New fossil mammals found at the base of Acantilados II Allomember of the La Meseta Formation, from the early Eocene (Ypresian) of Seymour Island, represent the oldest evidence of this group in Antarctica. Two specimens are here described; the first belongs to a talonid portion of a lower right molar assigned to the sparnotheriodontid litoptern Notiolofos sp. cf. N. arquinotiensis. Sparnotheriodontid were medium‐ to large‐sized ungulates, with a wide distribution in the Eocene of South America and Antarctica. The second specimen is an intermediate phalanx referred to an indeterminate Eutheria, probably a South American native ungulate. These Antarctic findings in sediments of 55.3 Ma query the minimum age needed for terrestrial mammals to spread from South America to Antarctica, which should have occurred before the final break‐up of Gondwana. This event involves the disappearance of the land bridge formed by the Weddellian Isthmus, which connected West Antarctica and southern South America from the Late Cretaceous until sometime in the earliest Palaeogene.  相似文献   

17.
Fossil wood is subject to different taphonomic, sampling and recognition biases in the palaeobotanical record when compared with leaves and palynomorphs. Wood therefore provides a systematically independent source of information that can increase our knowledge of past biodiversity and environments. Increase in fossil wood records from Cretaceous and Tertiary sediments helps further the understanding of trends in anatomical specialization through geological time. These data can then be used to distinguish such specialization from anatomical response to environmental change. Two case studies, a Late Cretaceous early Tertian' wood flora from Antarctica and a lower Tertiary w ood flora from southern England, have been used to exemplify the importance of studying the fossil wood component of palaeofloras.  相似文献   

18.
A fossil Mycetophilidae from the Aptian Crato Formation—Cretomanota gondwanica gen. nov., sp. nov.—is described, which is the first mycetophilid from the Crato Formation and corresponds to the oldest known fossil leiine and only the second Gondwanan fossil mycetophilid described so far. Cretomanota gondwanica and both species of Alavamanota Blagoderov and Arillo were added as terminals to the data matrix of a general phylogenetic analysis of the Mycetophilidae, and both fit into the Leiinae. Alavamanota is monophyletic, sister to the clade composed by Cretomanota and the extant genus Manota Williston. The biology of the extant members of this fungivorous family corroborates the reconstruction of the Crato palaeoenvironment as including woodlands with humid habitats and microhabitats. The presence of a Cretaceous member of the tribe Manotini at low latitudes in South America reinforces the hypothesis that the clade with all manotines except Leiella Edwards corresponds to a Lower Cretaceous offshoot from a group in southern Gondwana expanding its distribution to more northern areas into the Gondwana and into Laurasia.  相似文献   

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