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Mantalania longipedunculata De Block & A.P. Davis, a new species of Rubiaceae (Gardenieae) from Île Sainte Marie, Madagascar, is described, illustrated, and compared with the three other species in the genus. An extinction risk assessment is given, using the categories and criteria of the World Conservation Union (IUCN).  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 421–424.  相似文献   

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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   

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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   

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First record of fossil Mesozoic Ctenopoda (Crustacea, Cladocera)   总被引:1,自引:0,他引:1  
Pre-Pleistocene representatives of the crustacean order Ctenopoda Sars, 1865 are unknown. Here we describe Mesozoic fossil specimens of ctenopods from two localities in Mongolia: Khotont (Jurassic/Cretaceous boundary, about 145 Mya) and Khutel Khara (Lower Cretaceous, about 129 Mya). All specimens apparently belonged to the tribe Latonini Korovchinsky, 1986 of the subfamily Sidinae Baird, 1850. At the Khotont site, ctenopods were the most numerous microscopic animal fossils. We assigned these cladocerans to a new genus and species Archelatona zherikhini gen. nov., sp. nov. Our findings support a pre-Cretaceous origin for cladocerans.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 146 , 269–274.  相似文献   

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Magnolia polytepala Law, R.Z. Zhou & R.J. Zhang sp. nov. (Magnoliaceae) a new species from Fujian, south-east China, is described and illustrated. The species was found growing only in the evergreen broad-leaved forests of Mount Wuyishan at altitudes of 500–1200 m. Notes are also presented on the phenology and conservation status of the new species. It is closely related to Magnolia liliiflora Desr., but differs from the latter in its stunted habit (less than 2 m tall) and tepals, which are more numerous (12–16) and not contorted at the base.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 289–292.  相似文献   

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The skull and cervical anatomy of the sabre-toothed felid Paramachairodus ogygia (Kaup, 1832) is described in this paper, with special attention paid to its functional morphology. Because of the scarcity of fossil remains, the anatomy of this felid has been very poorly known. However, the recently discovered Miocene carnivore trap of Batallones-1, near Madrid, Spain, has yielded almost complete skeletons of this animal, which is now one of the best known machairodontines. Consequently, the machairodont adaptations of this primitive sabre-toothed felid can be assessed for the first time. Some characters, such as the morphology of the mastoid area, reveal an intermediate state between that of felines and machairodontines, while others, such as the flattened upper canines and verticalized mandibular symphysis, show clear machairodont affinities.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 363−377.  相似文献   

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Paradoris , traditionally a generic taxon of discodorid sea slugs, is revised for the first time. One hundred and thirty specimens were examined, including all types and most of the nontype specimens available. New records for Paradoris are provided: South Africa, Tanzania, Seychelles, Western Australia, Thailand, Philippines, shallow waters of New Caledonia, southern Japan, and Hawaii. The individual variation of all taxonomic characters is thoroughly evaluated. Prior to the present study, Paradoris included 15 nominal species: 12 valid names and three synonyms. Three additional names, Discodoris erythraeensis , D. lora , and D. cavernae , are re-allocated to Paradoris , based on phylogenetic analysis. A phylogenetic diagnosis is provided for Paradoris : in particular, two new synapomorphies are described. Eight species names are regarded as valid: P. araneosa , P. dubia , P. erythraeensis , P. indecora , P. liturata , P. lopezi , P. mulciber , and P. tsurugensis . However, most of these species are poorly known, i.e. from very few specimens, and their taxonomic status might change when more individuals are available. P. lora is regarded as a nomen dubium . Six new synonymies are proposed, and explained by the fact that: (1) species names were created for one or a few specimens, without considering individual variation; (2) authors have not worked within a phylogenetic framework and have created new species names without considering all the existing species names already available within Paradoris . Three new morphospecies are described, but not formally named because their taxonomic status is still uncertain for several reasons (e.g. lack of knowledge of individual variation for some critical features).  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 147 , 125–238.  相似文献   

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Five new species of land snail (family Enidae) are described from La Gomera (Canary Islands) of which the majority, on the basis of anatomy alone, could be incorporated within a new supraspecific taxon. In addition to the morphological study of these new species, a region of the 16S mitochondrial gene is sequenced from three of the new species and a range of species of Napaeus from within its two subgenera ( Napaeinus and Napaeus ) . There is a disparity between the morphological and preliminary molecular phylogenetic data. Possible explanations for this conflict are discussed, as well as the evolutionary relationships among these different taxa, and it is suggested that this group may be an excellent model for further studies of adaptation and diversification.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 169–187.  相似文献   

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Borassus akeassii Bayton, Ouédraogo & Guinko sp. nov. (Arecaceae) is described as a new species from western Burkina Faso in West Africa. It has been confused with the widely distributed African species B. aethiopum and more recently with the Asian B. flabellifer . However, it is distinguished by its glaucous, green leaves with weakly armed petioles and a characteristic pattern of lamina venation. The fruits have a pointed apex and are greenish when ripe, and the flowers of the pistillate inflorescence are arranged in three spirals. The pollen has a reticulate tectum and distinctive ornamentation. The distribution of B. akeassii is discussed and the status of the varieties of Borassus aethiopum (var. bagamojensis and var. senegalensis ) is examined.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 419–427.  相似文献   

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Hieracium petrovae Vladimirov & Szeląg sp. nov. , a new diploid (2 n  = 18) species in H. sect. Pannosa Zahn, is described and illustrated from the Rhodope Mountains, South Bulgaria, and compared with related taxa. It grows in relict habitats in crevices of limestone rock together with many Balkan endemics. H. petrovae is morphologically similar to taxa from the H. pannosum , H. pilosissimum and H. heldreichii groups (collective species sensu Zahn) to some of which it is a presumed ancestral species.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 261–265.  相似文献   

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The publication of the scientific name Monjurosuchus splendens in 1940 documented the first tetrapod fossil of the later world-renowned Jehol Biota. For more than half a century since this discovery, however, Monjurosuchus has remained as a monotypic genus of the family Monjurosuchidae, and the relationships of the family with choristoderes have not been correctly recognized until quite recently. In this paper, a new monjurosuchid is named and described based on a nearly complete skull and postcranial skeleton from the Early Cretaceous Chiufotang Formation exposed near Chaoyang, western Liaoning Province, China. This new material documents the first occurrence of monjurosuchid choristoderes outside the type Lingyuan area, and extends the geological range of the family from the Yixian Formation to the younger Chiufotang Formation. Cladistic analyses were conducted with inclusion of monjurosuchids, and the results support the placement of the family Monjurosuchidae as a primitive clade outside the Neochoristodera. A new classification scheme is proposed for choristoderes on the basis of the recovered phylogenetic framework of the group.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 145 , 427–444.  相似文献   

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A distinctive new species of dwarf monocaulous Coffea (Rubiaceae) from Cameroon is described and illustrated. Coffea mapiana is the second dwarf monocaulous known from Cameroon. Its diagnostic characters are elucidated and its taxonomic affinities are discussed; a conservation assessment is provided.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 425–430.  相似文献   

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A revised classification of the species of Cyathocalyx (Annonaceae) occurring in western Malesia (Peninsular Malaysia, Sumatra, and Borneo) is presented, with distribution maps. Fifteen species are recognized, including two that are newly described from Borneo ( C. angustipetalus and C. magnifructus ), which are illustrated. Several important nomenclatural changes are validated, including the elevation of Drepananthus carinatus var. deltoideus to specific rank as C. deltoideus , and the transfer of the name Parartabotrys hexagynus to Cyathocalyx as C. hexagynus . Other notable nomenclatural changes include the reduction of the name C. scortechinii to synonymy with C. pubescens .  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 513–532.  相似文献   

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Noccaea camlikensis sp. nov. (Brassicaceae) is described and illustrated from a localized serpentine range in southern Turkey. Its close relationship to N. cariensis , from which it differs in leaf and carpological characters, is discussed. The protologue of this fairly unknown species can now be amended to cover better the morphological variability of this taxon. A comparative study of seed-coat anatomy advocates its move from Thlaspi to Noccaea ; the relevant combination N. cariensis (Carlström) Parolly, Nordt & Aytaç is made. The ecology of both vicarious species is discussed and their distribution mapped.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 409–416.  相似文献   

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Despite some remarkable recent discoveries, the Mesozoic fossil record of salamanders remains limited, particularly for the Jurassic. Here we describe the first articulated salamander skeleton from the Jurassic of Euramerica, recovered from Upper Jurassic deposits of the Morrison Formation, Dinosaur National Monument, USA. The specimen was studied using both conventional methods and high-resolution computed tomography. It shows a combination of primitive and derived character states that distinguish it from all known Mesozoic salamanders and which permit the erection of a new genus and species, Iridotriton hechti . The derived states (including the presence of spinal nerve foramina in the tail) suggest a position on the stem of the Salamandroidea. Together with microvertebrate material from Britain, Portugal, and North America, this specimen confirms the presence of both stem- and crown-group salamanders in Euramerica from the Middle Jurassic (Bathonian) onwards, paralleling their evolution in Central and eastern Asia. This, in turn, provides qualified support for the current vicariance model of salamander evolution whereby basal caudates on an undivided Laurasian plate became separated into two populations by the incursion of the Turgai Sea in the Middle Jurassic, yielding Cryptobranchoidea in Asia and Salamandroidea in Euramerica.  © 2005 The Linnean Society of London , Zoological Journal of the Linnean Society , 2005, 143 , 599−616.  相似文献   

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