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1.
Abstract:  Previously known from the Kimmeridgian–Portlandian of Dorset (UK) only, Protocupressinoxylon purbeckensis wood is reported here from the Kimmeridgian of Asturias (Spain) and Ajoie (Switzerland). The morphospecies taxonomy and nomenclature are discussed, and new supplementary illustrations are given. The P. purbeckensis tree was growing in dry strongly seasonal (tropophilous) environments, and the new occurrences suggest that such a climate prevailed on land all over southwestern Europe at the end of the Jurassic (Kimmeridgian sensu anglico – Portlandian). The review of fossil wood data indicates that such a stressful environment may have constrained terrestrial biocoenoses and their evolution at the Jurassic/Cretaceous boundary. But wood generic diversity curves are also strikingly similar to that drawn 20 years ago for nonmarine tetrapods, implying a fossil Lagerstätte effect.  相似文献   

2.
Abstract:  The Cambrian index fossil Treptichnus pedum is reported from the Puerto Blanco Formation near Pitiquito, Sonora, Mexico, and new occurrences of the Neoproterozoic index fossil Cloudina are reported from the underlying La Ciénega Formation. Considered together, these fossils constrain the location of the Ediacaran/Cambrian boundary in Mexico. The suite of fossils in this sequence is important because it provides an independent biostratigraphic datum for constraining the position of Laurentia during the onset of metazoan diversification, for testing proposed lithostratigraphic correlations among western North American Neoproterozoic–Cambrian successions, and for testing regional tectonic paradigms such as the Mojave-Sonora Megashear hypothesis.  相似文献   

3.
A new species of fossil Tubulidentata has been found by the Mission Paléoanthropologique Franco-Tchadienne in Northern Chad. It is the first fossil Orycteropodidae (aardvark) from the Mio-Pliocene of Central Africa. The new taxon, Orycteropus abundulafus sp. nov. , is considered in the framework of the available Orycteropodidae fossil record. The Chadian specimen is characterized by the highest dental robustness index among all Tubulidentata, the presence of crests on the pterygoid, the triangular-shaped olecranon fossa and the reduction of the deltoid crest. All of these characters are linked to a less fossorial animal that had a tougher diet. This new African species is closer to the Eurasian O. gaudryi than to any other Tubulidentata. Together they form a clade distinct from that which includes O. afer . This is the first evidence of a relationship for aardvarks between Africa and Eurasia. An initial step is made towards revision of the phylogeny of the order.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 109–131.  相似文献   

4.
Numerous fruits and seeds of Ruppia are reported from the Upper Pliocene (2.3–3.5 Myr ago) Zhangcun Formation in Yushe Basin, Shanxi, northern China. They are the first fossil Ruppia from China and demonstrate the importance of fruit and seed fossils in recording genera not represented by fossil leaves. These Ruppia are characterized by possessing a small oval endocarp, smooth endocarp surface, distinct elliptical external depressions, distinct apical mucro, slightly curved seed shape and conspicuous globose hilum. A new species, R. yushensis Zhao, Collinson and Li, is described from these endocarp and seed features. Comparison with the two European Miocene species, R. palaeomaritima Negru and R. maritime-miocenica Szafer, indicates the existence at that time of three different geographical and stratigraphical species. R. yushensis constitutes the first Pliocene record of Ruppia and extends the range of fossils of this genus from Europe to eastern Asia. R. yushensis is the only aquatic plant in the uppermost middle part of the Zhangcun Formation. This monotypic occurrence indicates a brackish, clear, tranquil and shallow lake in this region in the Late Pliocene. The smooth endocarp surface further suggests a warm temperate or temperate palaeoclimate.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 317–329.  相似文献   

5.
David Penney 《Palaeontology》2004,47(2):367-375
The oldest described fossils of the extant spider family Araneidae (Araneinae; gen. et sp. indet.), the extant genus Orchestina (Oonopidae; O. sp. indet.) and the new fossil genus Palaeosegestria (Segestriidae; P. lutzzii gen. et sp. nov.) are presented from Upper Cretaceous amber of New Jersey. The known fossil range of the extant family Araneidae is extended approximately 50 myr from the previously oldest described araneid from the Middle Eocene oil shales of the Messel pit in Hesse, Germany. The fossil range of the extant genus Orchestina is also extended 50 myr from the previously oldest described specimen in Eocene Baltic amber.  相似文献   

6.
All known populations of koa-finches, genus Rhodacanthis , became extinct in the Holocene epoch. Two new species are described here from Quaternary fossil sites in the Hawaiian Islands. One new species, from Kauai and Maui, is roughly the size of the historically known greater koa-finch ( R. palmeri ) but differs in having a more robust skull and in bill morphology. The second new species, from Oahu and Maui, is similar in size to the lesser koa-finch ( R. flaviceps ) but closer to R. palmeri in qualitative osteological traits. The two species of koa-finches known historically from the island of Hawaii are distinct in osteology from the fossil koa-finches on the older Hawaiian islands, indicating that at least two of the four known speciation events in the genus took place within approximately the past 500 kyr. However, the similarity of maxillae from Pleistocene and Holocene sites on Oahu suggests that the Oahu population maintained morphological stasis through the climate changes of the late Quaternary. The evidence that speciation occurred on the youngest island in the archipelago suggests that the process of community assembly on newly emergent Hawaiian landscapes was a stimulus to evolutionary diversification in Rhodacanthis .  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 527–541.  相似文献   

7.
AN ARCHAIC SLIME MOULD IN BALTIC AMBER   总被引:1,自引:0,他引:1  
Abstract:  Several sporocarps of a slime mould are preserved on a plant fragment in a piece of Baltic amber (Tertiary, Eocene). The fossil is assigned to the extant genus Protophysarum (Myxomycota sensu stricto , Physarales) and described as P. balticum sp. nov. It is the third record of fossil sporocarps of a slime mould and the second record of the subclass Myxogasteromycetidae. All three records of fossil sporocarps are inclusions in Baltic amber. The find provides new insights regarding the occurrence and phylogeny of myxomycetes in the Palaeogene.  相似文献   

8.
Abstract:  Two new fossil psittaciform birds from the Lower Eocene 'Mo Clay' (Fur Formation) of Denmark ( c . 54 Ma) are described. An unnamed specimen is assigned to the extinct avian family of stem-group parrots, Pseudasturidae (genus and species incertae sedis ), while a second ( Mopsitta tanta gen. et sp. nov.) is the largest fossil parrot yet known. Both specimens are the first fossil records of these birds from Denmark. Although the phylogenetic position of Mopsitta is unclear (it is classified as family incertae sedis ), this form is phylogenetically closer to Recent Pstittacidae than to other known Palaeogene psittaciforms and may, therefore, represent the oldest known crown-group parrot.  相似文献   

9.
Abstract:  A recent collection of actinopterygian fossil fishes from a previously unreported locality in the Cenomanian or Turonian of southeastern Morocco includes a single specimen of a macrosemiid fish. Macrosemiids are more common in Jurassic and Early Cretaceous deposits, with the previously known range of the family being Late Triassic through Aptian or Albian. This discovery therefore extends the temporal range of the family into the Late Cretaceous. Moreover, macrosemiids had not previously been reported from northern Africa or the Moroccan area of the Tethys basin; therefore, this fossil also increases the geographical range of the family. The Moroccan macrosemiid is described in a new genus and species, Agoultichthys chattertoni . A phylogenetic analysis places it basal to all other genera of the family with the exception of Notagogus . Diagnostic characters of the new species include the high number of scales laterally along the body and the greater number of dorsal fin rays than in other members of the family.  相似文献   

10.
This paper presents a life cycle assessment (LCA) of industrial scale microalgae biomass production in compact photobioreactor (PBR) systems (2 × 5 × 8 m) for supplying biofuel/electricity generation processes and synthesis of new materials. Other objectives are as follows: (i) to compare the impact of various raw materials, substances, and services; and (ii) to evaluate environment‐relevant aspects of the proposed system as compared to microalgae raceway ponds. The life cycle inventory assessment shows that (i) only atmospheric CO2 is used for PBR microalgae cultivation, whereas in raceway ponds, injection of CO2 from fossil origin is largely required to allow for microalgae growth; and (ii) the PBR daily production rate of dry biomass is currently at 1.5 kg m?3 day?1 for each PBR, which is 12.82 times larger than the reported average 0.117 kg m?3 day?1 raceway ponds production. It is found that in general the association of the effects of the production of steel, PVC, and the packaging contribute to more than 85% of the total impact in each analyzed category. Therefore, to achieve PBR biomass production impact reduction and sustainability, PVC and steel utilization need to be minimized, as well as packaging materials. Based on the PBR LCA results, that is, due to no CO2 injection from fossil origin and low area occupation, it is expected that high density production of truly renewable microalgae biomass could be obtained from PBR systems.  相似文献   

11.
Abstract:  A new Lower Devonian sea spider (Arthropoda: Pycnogonida) from the Hunsrück Slate, Germany, is described as Flagellopantopus blocki gen. et sp. nov. This is only the sixth fossil pycnogonid species to be described. Its most remarkable and unique aspect is the long, flagelliform telson. Although our fossil apparently lacks chelifores (an apomorphy), the retained telson and the segmented trunk end behind the last pair of legs resolve F. blocki to a fairly basal position in the pycnogonid stem lineage. It probably lies between Palaeoisopus problematicus Broili, which has a lanceolate telson and the most trunk segments of any sea spider, and all other Silurian–Recent Pycnogonida. Our new material shows that at least two fossil pycnogonids retained a telson, albeit with very different morphologies, and further supports the idea that a greater diversity of body plans existed among the Palaeozoic pycnogonid taxa.  相似文献   

12.
DAVID PENNEY 《Palaeontology》2006,49(4):899-906
Abstract:  The Neotropical fossil amber Hersiliidae are revised. Prototama Petrunkevitch is a senior synonym of both Priscotama Petrunkevitch and Neotama Baehr and Baehr. Fictotama Petrunkevitch and Perturbator Petrunkevitch are removed from synonymy and are considered nomina dubia because the fossils are poorly preserved. The following new combinations are established for the fossil fauna: Prototama antiqua (Petrunkevitch), P. maior (Wunderlich), P. media (Wunderlich), and P. minor (Wunderlich), and for the extant fauna: P. cunhabebe (Rheims and Brescovit), P. forcipata (F. O. P.-Cambridge), P. longimana (Baehr and Baehr), P. mexicana (O. P.-Cambridge), P. obatala (Rheims and Brescovit), P. punctigera (Baehr and Baehr), P. rothorum (Baehr and Baehr) and P. variata (Pocock) (all ex Neotama ). It is predicted that at least one undiscovered, extant Prototama species exists on Hispaniola. Hersiliidae have a diverse fossil record. The presence of Oecobiidae, the sister taxon of the Hersiliidae, in New Jersey and Lebanese ambers predicts a minimum geological age of Early Cretaceous for the family. Fossils are of paramount importance in studies of historical biogeography but were not considered in earlier hypotheses regarding the palaeogeographical origins of the family. Previous conclusions that Hersiliidae originated in Africa are here considered to be speculative and unsupported.  相似文献   

13.
We provide the first evidence of a small-headed fly planidium (first instar larva; Diptera: Acroceridae) associated with a whirligig mite (Acari: Acariformes: Prostigmata: Anystina: Anystidae) in Baltic amber. This fossil is surprising as parasitic nematodes are the only metazoans known to successfully attack acariform mites, and Acroceridae are believed to be host-restricted parasitoids of spiders. The fossil corroborates a previously published, but widely dismissed, paper that first reported parasitism of parasitengone mites by acrocerid planidia. The possible natural history implications of this find are discussed.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 9–13.  相似文献   

14.
The historic biogeography of the aquatic fauna of the Levant is reconstructed upon evidence of the gastropod groups with a well-established taxonomy and a rich fossil record. Faunal origins include ancient northern elements coming from an Anatolian–Iberian faunal province that, in the early Miocene, bypassed mainland Italy. This scenario is more plausible than the current 'Lago Mare' biogeographical theory. Palaeotropical elements represent either an Oriental or an African source; in either case these elements could have first reached Anatolia, from where they eventually spread southwards into the Levant, perhaps broadly coinciding in time with the invasion of the northern elements. Within the Levant, the faunas of the Euphrates, Orontes, and Jordan formed at first one common pool, but by 2 Mya the fauna of the Jordan had diverged from that of the Orontes; later, the Orontes fauna diverged from that of the Euphrates. By 1.4 Mya the fauna of the Levant consisted of both ancient survivors and new species. Some 780 000 years ago there was an exceptionally diversified fauna with many new, northern elements. Many of these elements did not survive to recent times. The fossil record suggests that the fauna of the Jordan Valley was separate from that of the Orontes throughout the Pliocene–Pleistocene. Taxa common today to the Jordan Valley and coastal sites may reflect an ancient system of rivers that drained westwards to the Mediterranean Sea, across the Jordan Valley of today.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 92 , 625–639.  相似文献   

15.
A well-preserved pollen cone of the genus Ginkgo was found in the Yixian Formation (Early Cretaceous) of Liaoning Province, China, and is described as the new species Ginkgo liaoningensis . The pollen cone, catkin-like, consists of a main axis bearing scales at its base and spirally arranged sporophylls bearing 3–4 (−2) oval or elliptical sporangia. The sporangia are pendulous and dehiscent by a longitudinal slit. The mature pollen grains are monocolpate and elongate-elliptical, and the juvenile pollen grains are found in the tetrad stage. The characteristics of G. liaoningensis are very similar to those of the living Ginkgo biloba , but the sporophylls of G. liaoningensis bear 3–4 (−2) sporangia, whereas those of G. biloba bear mostly two sporangia. G. liaoningensis differs from fossil cones of Ginkgo huttoni from the Jurassic of Yorkshire, UK, and an unnamed specimen of Ginkgo from the Upper Cretaceous of Alberta, Canada, in the size and number of sporangia. The comparison between G. liaoningensis (fossil) and G. biloba (living) supports the reduction hypothesis of ovule organs in Ginkgo , with the number of sporangia having experienced the process of reduction from three or four to two since the Early Cretaceous.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 133–144.  相似文献   

16.
Aim   To examine the issue of Beringian steppe-tundra from an entomological standpoint, using fossil beetle data collected from late Pleistocene sites.
Location   North-eastern Siberia (Western Beringia), the Bering Land Bridge (Central Beringia), and Alaska and the Yukon Territory (Eastern Beringia).
Methods   Analysis of habitat preferences of beetle species found in fossil assemblages, leading to classification of major habitat types characterized by the faunal assemblages.
Results   Fossil beetle assemblages indicative of steppe-tundra are found mainly in the interior regions of Eastern Beringia, whereas these assemblages dominate nearly all late Pleistocene fossil sites in Western Beringia. Eastern Beringian faunas contain a much larger proportion of mesic to hygrophilous species and very few arid-habitat species. In contrast to this, the habitat requirements of the Western Beringian faunas are more evenly spread across the moisture spectrum.
Main conclusions   The taxonomic patterns of the two sets of fossil assemblages are remarkably different. Eastern Beringian faunal assemblages contain substantial numbers of mesic tundra and riparian rove beetles (Staphylinidae); this element is almost entirely lacking in the Western Beringian fossil assemblages. Taphonomic bias tends to overemphasize moisture-loving species at the expense of dry, upland species in the fossil record. Both Western and Eastern Beringian landscapes undoubtedly contained mosaics of habitats ranging from dry uplands (steppe-tundra) through mesic tundra to bogs and riparian corridors.  相似文献   

17.
Lacustrine interbeds of a volcaniclastic succession that crops out extensively in north-western Patagonia yielded impressions of articulated, nearly complete, frogs of different ontogenetic stages including tadpoles. The stratigraphic position of the fossil bearing beds in this sequence and evaluation of palaeofloristic data against the record of climatic change in southern high latitudes support a middle Eocene – early Oligocene age for the frogs. These frogs are described as a new genus and species that resembles the late Palaeocene ' Xenopus' romeri from Brazil, and differs from the middle Eocene S. pascuali from Patagonia, in the relatively wide and short braincase and fused first two presacral vertebrae. However, unlike ' X. '  romeri , the nasals are paired and bear short, but distinct, rostral processes. A parsimony analysis based on 49 adult osteological characters demonstrates that these South American fossil pipids are closely related to xenopodines, restricted to the African continent today, although their interrelationships remain poorly resolved. Interpretation of the ontogenetic stages exemplified by the fossil specimens suggests a developmental pattern more similar to that of extant xenopodines than to the ontogeny of more distant pipoid relatives. Moreover, the similarity between these fossil larvae and those of Xenopus and Silurana strongly suggests similar habits. Many of these larval features may be considered as caenogenetic, i.e. specializations of the tadpoles as obligate, microphagous suspension feeders.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society , 2003, 139 , 439-476.  相似文献   

18.
A new fossil hydroid is reported as an organic impression on a calcareous gastropod steinkern from the Prairie Bluff Chalk (Maastrichtian), Oktibbeha County, Mississippi. This is the first such hydroid reported from the Upper Cretaceous of the Atlantic Coastal Plain. The fossil organism consists of anastomosing hydrorhizae forming a holdfast, a fascicled hydrocaulus, and elongated, crenulated and ribbed hydrothecae. The fossil is unlike other Mesozoic hydroids that have been reported from Europe and North America; it is described as Mesodendrium oktibbehaensis gen. et sp. nov. and tentiatively referred to an extant family, the Campanulariidae (Calyptoblastina). The complete preservation of the holdfast, hydrocaulus and hydrothecae suggests that this hydroid lived inside gastropod shells. In analogy with Recent symbiotic hydroids inhabiting mollusc shells, the new specimen described here possibly represents the oldest known example of a symbiotic relationship between hydroids and hermit crabs.  相似文献   

19.
It is generally assumed that the Neogene crocodylian fauna of Europe has been represented only by brevirostrine alligatoroid Diplocynodon and longirostrine false gharials ( Gavialosuchus and/or Tomistoma ), which became extinct prior to 6 Mya. Although several lines of evidence suggest that Crocodylus originated in Africa during the Miocene and then promptly dispersed to other continents, the occurrence of this genus in Europe has never been rigorously proven and the traditional palaeontological approach failed to identify a monophyletic group of fossil Crocodylus (simply leading to a proliferation of extinct taxa). The new remains reported here, from an endemic insular fauna from southern Italy, Late Messinian to earliest Pliocene in age (5–6 million years old), represent the youngest European crocodylian, and allow, for the first time in a phylogenetic context, an unambiguous demonstration that Crocodylus dispersed into Europe, possibly during the Tortonian. If the peculiar morphology of the medial maxillary edge is interpreted as evidence for a medial dorsal boss, the southern Italian Crocodylus could be related to C. checchiai from the late Neogene of Libya. The presence of this African immigrant in Europe confirms the role of climate change for faunal dispersal and island colonization.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 149 , 293–307.  相似文献   

20.
Abstract:  A new arthropod, Synophalos xynos gen. et sp. nov., is described from the Lower Cambrian of the Chengjiang Lagerstätte, Yunnan, China. It is provisionally assigned to Crustacea, Waptiida and Waptiidae. Just one example of an isolated individual of S .  xynos is known. Typically, individuals of the new species occur together in similar, robustly integrated chain-like associations. Such a strongly linked configuration is apparently unique for any arthropod, fossil or living. The chain-like association is suggested to represent an example of collective behaviour, possibly associated with reproduction, or more likely migration.  相似文献   

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