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1.
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   

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The new species Ceratozamia vovidesii from a Pleistocene floristic refuge in southern Mexico is described and illustrated. It show an affinity with C. matudae Lundell and C. mirandae Vovides, Pérez-Farrera & Iglesias from Chiapas, but it differs from them in leaf, male and female cones, and trunk morphology.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 393–400.  相似文献   

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Several house gecko species of the genus Hemidactylus are almost cosmopolitan lizards, with distributions that have probably been shaped by natural transoceanic dispersal as well as by more recent human introductions. Here we revise the Hemidactylus populations of Madagascar and compare them genetically with populations from other sites in the Indian Ocean region. Morphological data strongly confirm the occurrence of three Hemidactylus species on Madagascar: Hemidactylus frenatus , distributed along the western coast of Madagascar; H. platycephalus , restricted to the north-west and the widespread H. mercatorius that occurs throughout the island, including coastal areas at sea level as well as big cities (Antananarivo, Fianarantsoa) at altitudes of 1200–1300 m above sea level. Analyses of partial sequences of the 16S rRNA gene in 46 Hemidactylus specimens from Madagascar, East Africa, South Asia, and the Comoro and Mascarene archipelagos demonstrated the presence of a fourth species, H. brooki, on the Mascarenes (Réunion, Rodrigues, and Mauritius) and Comoros (Moheli). The Malagasy populations of H. platycephalus were genetically uniform and differentiated from the African and Comoroan specimens studied. H. frenatus had a relatively low genetic differentiation over the whole region with no recognizable phylogeographical structure, indicating more recent colonizations or introductions. In contrast, H. mercatorius showed a strong phylogeographical structure of haplotypes, with two distinctly different lineages in Madagascar. Moreover, all Malagasy specimens differed strongly from the single African specimen included. This indicates that populations of H. mercatorius in Madagascar have a long history that predates human settlement.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 83 , 115–130.  相似文献   

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Two new taxa in Stipa L. Sect. Leiostipa Dumort., S. alba and S. letournexii ssp. ignea , are described from southern Tunisia (northern Africa). In addition, the S. letournexii complex is reviewed and a new combination, S. letournexii ssp. tunetana (H.Scholz) F.M. Vázquez, is presented.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 439–444.  相似文献   

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We report complete mitochondrial genomic sequences for Crocodylus acutus and Crocodylus novaeguineae, whose gene orders match those of other crocodilians. Phylogenetic analyses based on the sequences of 12 mitochondrial protein-coding genes support monophyly of two crocodilian taxonomic families, Alligatoridae (genera Alligator, Caiman, and Paleosuchus) and Crocodylidae (genera Crocodylus, Gavialis, Mecistops, Osteolaemus, and Tomistoma). Our results are consistent with monophyly of all crocodilian genera. Within Alligatoridae, genus Alligator is the sister taxon of a clade comprising Caiman and Paleosuchus. Within Crocodylidae, the basal phylogenetic split separates a clade comprising Gavialis and Tomistoma from a clade comprising Crocodylus, Mecistops, and Osteolaemus. Mecistops and Osteolaemus form the sister taxon to Crocodylus. Within Crocodylus, we sampled five Indopacific species, whose phylogenetic ordering is ((C. mindorensis, C. novaeguineae), (C. porosus, (C. siamensis, C. palustris))). The African species C. niloticus and New World species C. acutus form the sister taxon to the Indopacific species, although our sampling lacks three other New World species and an Australian species of Crocodylus.  相似文献   

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Cluster analysis and principal coordinates analysis were used to investigate phenetic variation in Cineraria deltoidea , a species that ranges from near sea level in KwaZulu-Natal, South Africa, to 4300 m a.s.l. on the mountains of East Africa and Ethiopia. Earlier taxonomic revisions reduced nine previously recognized species to synonyms of C. deltoidea . Two closely related species, C. decipiens and C. atriplicifolia , were also included in the analyses. Thirty-six morphological characters were examined on 111 specimens. Phenograms and scattergrams show partial clusters of specimens of C. deltoidea from individual mountains or geographical regions, but no groups are sufficiently distinct to warrant formal recognition at any rank. The East African specimens from 3000 m a.s.l. and higher tend to cluster together. Growth at high altitude in East Africa is correlated with fewer, larger capitula on longer peduncles, and an absence of a cobwebby indumentum comprising long, narrow-based trichomes. Cineraria deltoidea is thus a highly variable species with geographical and clinal variation evident throughout its range. Cineraria atriplicifolia and C. decipiens are maintained as distinct species, distinguished from C. deltoidea by their growth form, life span and auricle shape.  © 2007 University of the Witwatersrand, Johannesburg. Journal compilation © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 497–521.  相似文献   

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A taxonomic revision of the genus Flagenium Baill. is presented. Flagenium is endemic to Madagascar and comprises six species; three new species are described here ( F. farafanganensis , F. petrikensis , and F. pedunculatum ) and one species ( F. arboreum ) is transferred into synonymy. Each species is fully described, and summaries of distribution, habitat and ecology, and phenology are given; conservation assessments are provided for each species. Flagenium is characterized by having ovaries with at least two erect and two pendulous ovules per locule, which, depending on the species, can display an additional two to four horizontal ovules per locule arranged between the uppermost and lowermost ovules. In addition, Flagenium has a longitudinally ten-ribbed fruit. These features are potentially unique within the Octotropideae.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 557–570.  相似文献   

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Gondwanan biogeography has fascinated zoologists and botanists for over a century, but most biogeographical work has used continent-scale areas as analytical units. More finely resolved patterns, as can be obtained from small invertebrates with limited dispersal abilities, will be obscured in those studies. A common case is treating Australia as a single biogeographical region. In the present study, the necessity of splitting Australia into multiple microareas is demonstrated using centipedes as an example. The lithobiomorph centipede Paralamyctes is distributed on fragments of Gondwana, with species in southern Africa, Madagascar, southern India, Patagonia, eastern Australia, and New Zealand. A cladogram for Paralamyctes is based on morphology and sequences for four molecular markers for 30 terminals that sample 20 of 26 known ingroup species and four outgroups. Analysis with direct optimization across a range of indel costs and transversion : transition cost ratios identifies two main clades: Paralamyctes ( Paralamyctes ) unites species from southern Africa, Madagascar, tropical and warm temperate Australia, and New Zealand. The other group includes the temperate Australian/New Zealand Paralamyctes ( Haasiella ) and Paralamyctes ( Thingathinga ) and a Chilean clade. Subtree analysis finds that different parts of Australia have closest affinities to other Gondwanan fragments, and some of these relationships (such as that between north Queensland and New Zealand) are based on taxonomically stable clades. Area delimitation for large continental fragments should use sufficiently fine resolution to test the 'monophyly' of those fragments and attempt to eliminate spurious geographical paralogy.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 65–78.  相似文献   

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A taxonomic revision of broad-leaved Potamogeton species ascribed to the ' P. schweinfurthii–thunbergii complex' occurring in Africa and on surrounding islands is presented. Three species, P. nodosus , P. richardii and P. schweinfurthii , are recognized in the African mainland. The widespread species P. nodosus has been widely overlooked in sub-Saharan Africa. It is recorded here for the first time from eight countries of tropical and southern Africa and from six surrounding islands. The distribution of P. richardii is critically revised and the species is recorded for the first time from Cameroon, Swaziland and Madagascar. P. schweinfurthii is recorded for the first time from Algeria, Tunisia, Burkina Faso and Niger. The nomenclature of all three species is revised. Lectotypes are designated for six names. All original material of the name P. thunbergii Cham. et Schltdl. actually belongs to P. nodosus Poir. The correct name for the East and southern African species called ' P. thunbergii ' is P. richardii Solms. The lectotype of P. schweinfurthii designated by Dandy proved to be P. nodosus . A new type is therefore proposed for the species generally named P. schweinfurthii and the name itself is proposed for conservation. The morphology and stem anatomy of P. nodosus , P. richardii and P. schweinfurthii are described. In spite of some overlaps in the morphological variation in their vegetative characters, a detailed analysis of the variation patterns and instructions for reliable identification are given. The distributions of all three species are described, based solely on reliably identified specimens, many of which were also examined anatomically. Distribution maps are provided.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 329–357.  相似文献   

13.
Plagiochila sect. Vagae is a large pantropical clade that is characterized morphologically by frequent terminal branching, vegetative distribution by propagules on the ventral surface of the leaves and a capsule wall with thickenings in all layers. Plagiochila corrugata from Brazil is characterized by strongly undulate, toothed leaf margins and represents the only known neotropical species of sect. Vagae with unispiral elaters. Plagiochila cambuena from Madagascar is distinguished by the same features. Maximum likelihood and parsimony analyses of 38 nrDNA ITS sequences of Plagiochila reveal P. corrugata and P. cambuena in a weakly (ML) to well (MP) supported monophyletic lineage within P.  sect.  Vagae . As an outcome of the morphological and molecular investigation, P. cambuena is relegated to the synonymy of P. corrugata. Plagiochila corrugata is placed in a Vagae -subclade with 11 further American species. The range of P. corrugata can be ascribed to long-range dispersal from the Neotropics rather than a Gondwanan distribution. Species from tropical Asia and Africa are placed at the base of the Vagae clade. Branch length within P.  sect.  Vagae points to a sudden radiation.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 469–481.  相似文献   

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This paper offers a detailed taxonomic revision of all Canarian Pholcus species described before 2003, all of which are newly described and newly illustrated. Pholcus guadarfia sp. nov. is described, while a neotype for Pholcus malpaisensis Wunderlich, 1992 is also provided. In addition, we propose Pholcus gomerae Wunderlich, 1980 as a senior synonym for Pholcus gomeroides Wunderlich, 1987. More importantly, cladistic analysis based on the morphological characters of the Macaronesian Pholcus species was conducted for the first time. Parsimony analyses of 73 morphological characters revealed the close relationships between those species from the Canary Islands, Madeira and the Macaronesian enclave in Africa (between Agadir and Nouadhibou).  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 151 , 59–114.  相似文献   

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The plague has been present for a century in Madagascar; the only known reservoir is the black rat, which is also the main victim of this disease. Whereas the two plague foci are restricted to an altitude above 800 m, the black rat is distributed over the whole island, the only morphological variation being a within-site variability in belly colour. To resolve these apparent contradictions, an analysis of the different belly colour morphs and of populations living in different habitats and altitudes was undertaken. An allozymic study demonstrated that sympatric white- and grey-bellied rats ( N  = 26) living within the plague foci, all belonged to the same species: Rattus rattus . This specific assignment was confirmed by a chromosomal analysis which showed that all 90 individuals studied presented the same diploid number, 2 n  = 38, whatever the habitat and altitude. This study indicates that all specimens investigated in Madagascar could be referred to the same black rat species. Survival of rat populations, despite a century of coexistence with the plague, is most likely related to their high reproductive and recolonization potential, as well as selection of plague resistant genotypes. As the altitudinal limit of the plague foci does not seem to be related to characteristics of the rodent reservoir, investigations concerning the vectors are now essential.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 78 , 335–341.  相似文献   

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Tahina J.Dransf. & Rakotoarinivo, gen. nov. (Arecaceae) is described as a new genus from north-western Madagascar, with a single species T. spectabilis J.Dransf. & Rakotoarinivo, sp. nov. Tahina is included within tribe Chuniophoeniceae of subfamily Coryphoideae, based on the strictly tubular imbricate rachilla bracts, the flowers grouped in cincinni with tubular bracteoles, and the stalk-like base to the corolla. This position is corroborated by evidence from plastid DNA. Lamina anatomy is discussed in detail, and similarities with and differences from the other members of Chuniophoeniceae are discussed. Based on the ecological characteristics of the single locality, predictions are made on where else it may occur in Madagascar.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 79–91.  相似文献   

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The higher taxonomy of the 20 known genera of Afrotropical freshwater crabs is revised to reflect the evolutionary relationships revealed by the consensus of a series of recent morphological and molecular phylogenetic studies of the group. The Afrotropical freshwater crab genera fall into two monophyletic groups, one from Socotra with two genera (Potamidae) and another that includes the remaining 18 genera. The latter group, which includes the bulk of the region's freshwater crab fauna, forms a well-supported monophyletic clade. We recognize two monophyletic sister groups (subfamilies) within the Potamonautidae, one for seven genera from Africa (the Potamonautinae) and one for 11 genera from Africa, the Seychelles, and Madagascar (the Deckeniinae). The Deckeniinae includes two monophyletic groups (tribes), one with seven genera from Madagascar (the Hydrothelphusini), and one with four genera from Africa and the Seychelles (the Deckeniini). The Deckeniini is further divided here into two subtribes, the Deckeniina and the Globonautina. The Platythelphusidae is not recognized, and the Deckeniidae and Globonautinae are lowered in rank. There is no phylogenetic support for the continued inclusion of any genus from the Afrotropical region in the Gecarcinucidae which is treated here as an exclusively Oriental family. The Afrotropical freshwater crabs (excluding those from Socotra) form a monophyletic assemblage that has no representatives outside of the region. The wider biogeographical implications of the taxonomic revision are discussed.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 399–413.  相似文献   

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