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There have been numerous attempts to resolve the taxonomy of the two-horned chamaeleons of East Africa. However, the high levels of intraspecific variation and reported sympatry of morphologically distinct taxa indicate that their current classification is unsatisfactory. Tissue samples were collected from specimens from most mountain massifs (excluding the Nguu) where two-horned chamaeleons are known to occur and were used to sequence partial 12S and 16S rRNA, as well as ND2 mtDNA genes. These specimens and further museum material were used to review morphological variation and to define discriminating characters for each taxon. Phylogenetic analyses of gene sequences show clear genetic divergence between allopatric populations, although two lineages occur in sympatry in the East Usambara Mountains, and is supported by divergent morphology. In light of these results a formal revision of the taxonomy of all East African two-horned chamaeleons is proposed and seven species are recognized ( Kinyongia boehmei , K. fischeri , K. matschiei , K. multituberculata , K. tavetana , K. uluguruensis and K. vosseleri ). These taxa form a monophyletic group except for K. uluguruensis , which seems to be more closely related to one-horned species. Most of these taxa have been previously described and subsequently reduced to synonyms. Two other previously described two-horned taxa are not recognized as valid: Chamaeleo tornieri is considered species inquiriendae , and C. fischeri werneri is placed in synonymy with K. multituberculata . A dichotomous key is provided for the identification of these taxa and some aspects of their conservation, ecology and evolutionary origins are also discussed.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 367–391.  相似文献   

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A morphological (non-molecular) cladistic analysis of the Velloziaceae is presented. The terminal taxa are 47 species of Velloziaceae plus four taxa as outgroups: Acanthochlamys bracteata (Acanthochlamydaceae), Encholirium scrutor (Bromeliaceae), Thoracocarpus bissectus (Cyclanthaceae) and Pandanus racemosus (Pandanaceae). The species of Velloziaceae sampled represent a significant proportion of the morphological diversity of the family, including all recognized genera and sections. The analysis revealed two major groups within Velloziaceae, supported mainly by stomata, vascular bundles in the pedicel, aquiferous tissues, filaments, anthers, pollen, stigma, seeds, ploidy and chemical characters. Comparison between this and the previous phylogenetic hypotheses for Velloziaceae, together with the two conflicting current classifications, suggests that there is incompatibility concerning the support of current genera and sections. The only three groups supported in all phylogenies are Barbacenioideae sensu Menezes (= Barbacenia sensu Smith & Ayensu), Xerophyta sect. Barbacenioides and Xerophyta sect. Xerophyta sensu Smith & Ayensu.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 157–173.  相似文献   

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Flower and fruit specimens of 184 individuals were sampled to investigate patterns of intraspecific variation and to evaluate recognition of taxa within the Acer tschonoskii complex using morphometric analysis. Previous taxonomic treatments have considered A. tschonoskii var. rubripes (=  A. komarovii ) and A. tschonoskii var. tschonoskii to be separate species. The morphological discontinuity between these two taxa was evident in peduncle and pedicel length, and in number of flowers. In addition, the delimitations of some species within sect. Macrantha were clarified using these diagnostic characters. In view of the geographical distribution of the A. tschonoskii complex, which includes many taxa of sect. Macrantha from China to Japan through Korea, the long raceme with many flowers ( A. sikkimense ) and unlobed leaf are considered more primitive than the short raceme with a small number of flowers and five-lobed leaf ( A. maximowiczii and A. komarovii ). However, many intermediate taxa were present. This study also suggests that several Chinese taxa, such as A. metcalfii, A. taronense, A. hookeri and A. grosseri , may be subject to different taxonomic interpretation and should be reinvestigated morphologically.  © 2003 The Linnean Society of London. Botanical Journal of the Linnean Society, 2003, 143 , 29−42.  相似文献   

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Isoetes velata A. Braun is an amphibious plant with Mediterranean and Ibero-Atlantic distribution, showing marked morphological variability. Within the same geographical area, closely related restricted-range taxa are also present, including I. velata ssp. asturicense (restricted to mountainous areas of the north-west Iberian Peninsula) and I. boryana (restricted to the southern French Atlantic coast). These related taxa have unclear taxonomy and are both threatened. We performed a morphometric study of specimens of the three taxa. Our results suggest that I. velata ssp. asturicense is better considered as a distinct species, I. asturicense Laínz (Laínz), distinguishable from the other two taxa by mean megaspore length ( N  ≥ 30) < 360 µm. In contrast, our results do not support consideration of I. boryana as a separate species, and we here propose that this taxon be considered as a variety, I. velata A. Braun var. boryana M.I. Romero & C. Real stat. nov.   © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 459–464.  相似文献   

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The taxonomic position of western Asian members of Gentiana sect. Pneumonanthe has long been a matter of conflict. In this paper, the six western Asian species currently recognized as belonging to sect. Pneumonanthe ( G. boissieri , G. calycina , G. freyniana , G. gelida , G. paradoxa , and G. septemfida ) are compared and their relationships established using a morphological phylogenetic analysis. Seed testa and flower and leaf morphological characters were studied and 11 characters were selected for a cladistic analysis. Euro-Siberian and Far Eastern taxa of sect. Pneumonanthe ( G. pneumonanthe and G. scabra ) were used as outgroups. Our results suggest the presence of two morphologically distinct clades within the western Asian gentians: a Septemfida and a Gelida clade. G. calycina and G. freyniana show close affinities to G. boissieri and G. gelida , and are distinct from G. septemfida s.l. Biogeographical aspects of the two groups are discussed.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 197–208.  相似文献   

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A new species, Psephellus turcicus A.Duran & Hamzaoğlu (Asteraceae) in sect. Psephelloidei (Boiss.) Wagenitz & Hellwig is described and illustrated from Anatolia, Turkey. The species grows on limestone crevices in Kazankaya Canyon (A5 Yozgat) in central Anatolia. A neo-endemic confined to Kazankaya Canyon, it is closely related to Psephellus psephelloides (Freny & Sint.) Wagenitz. Diagnostic morphological characters from closely similar taxa are discussed, and arranged in a key of Turkish similar Psephellus Cass. The ecology, biogeography and conservation status of the species are also presented. Achene surface morphology of P. turcicus and P. psephelloides are examined by SEM. The geographical distribution of the new species and other related species is mapped.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 495–500.  相似文献   

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Recent molecular studies have clarified the problem of the generic limits of Carthamus . However, taxonomic problems remain in the sectional classification: section Carthamus was confirmed as a natural group, but molecular phylogenies based on DNA sequences did not resolve the other sections, resulting in a confusing conglomerate. A survey based on RAPD markers has been carried out in this conflicting group of sections, with the aim of evaluating the usefulness of these markers at the section and species levels. On the basis of the results, correlated with morphological and karyological characters, some recommendations are made in relation to the taxonomy of Carthamus . The number of sections is reduced from five to two: section Thamnacanthus is currently classified as a different genus, Phonus ; section Carthamus s.s. is retained in its present delimitation, and section Atractylis is redefined, including current sections Atractylis , Lepidopappus and Odontagnathius . The commonly accepted treatment of some taxa as subspecies is not well founded, and C. alexandrinus , C. creticus , C. tenuis and C. turkestanicus should be considered as independent species. Our results confirm that methodological problems posed by RAPD markers can be avoided by careful laboratory procedures and appropriate data analyses; they also suggest that this kind of marker is useful at low taxonomic levels and is, furthermore, complementary to DNA sequence analysis.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 375–383.  相似文献   

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A comprehensive taxonomic revision of the genus Maesa Forssk. (Maesaceae) occurring in the Philippines is presented for the first time. Thirteen species are recognized, including a newly described species, M. stonei , which is most similar to M. reflexa . Several previously used names are reduced to synonymy, including M. pachyphylla and M. undulata (both reduced to synonymy with M. cumingii ), and M. elmeri , M. laxa and M. ramosii (all reduced to synonymy with M. indica ). Extensive lectotypification has been necessary due to the destruction of many type specimens, particularly those of C. Mez (in B) and E. D. Merrill (in PNH). The conservation status of each species is determined using the IUCN red list categories and criteria.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 17–43.  相似文献   

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A new species, Oxalis ferae Llorens, Gil & Cardona (Oxalidaceae) from the Balearic islands (Spain) is described and illustrated. It is considered to be endemic to Mallorca. The morphological differences between the more closely related taxa of Oxalis section Corniculatae are discussed. IUCN threatened category and observations on the ecology of the populations are noted.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 489–493.  相似文献   

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A synoptic treatment of the Rubiaceae of São Tomé e Príncipe (Gulf of Guinea) is presented based on herbarium collections kept at BM, COI, K and LISC. There are 36 genera and 64 species of Rubiaceae represented in the flora of São Tomé e Príncipe. Identification keys are provided for genera, species and infraspecific taxa. A new combination is made in Chassalia . Twenty-nine taxa are endemic to these islands, two of which are also endemic to Annobon. The conservation status of the endemic taxa is assessed and IUCN categories of threat are proposed for ten taxa. Nineteen taxa of Rubiaceae are considered under threat in São Tomé e Príncipe and ten are considered nearly threatened.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 85–114.  相似文献   

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The species of Goniothalamus (Annonaceae) occurring in Peninsular Malaysia and Singapore are revised, updating the previous taxonomic treatment by James Sinclair, published in 1955. A total of 18 species is recognized, including a new species, G. tomentosus . Collections referrable to G. tomentosus were previously determined as ' G. marcanii '; examination of the types of G. marcanii reveals that the two taxa are not conspecific, however, and a new name is accordingly validated here. Goniothalamus tomentosus has closest affinities with the Javan/Sumatran species G. costulatus . Other important nomenclatural changes include the reduction of G. umbrosus to synonymy with G. tapis .  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 142 , 321−339.  相似文献   

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A new species of Achillea L., Achillea occulta Constantin. & Kalpoutz., from the summit area of Mount Koulochera in south-east Peloponnisos, Greece, is described and illustrated. It belongs to A . sect. Ptarmica and further, to a small group of taxa known under the illegitimate sectional name 'Anthemoideae'. In Greece, A. occulta has no close allies. The taxonomically related taxa, i.e. A. barrelieri (Ten.) Sch. Bip., A. mucronulata Bertol., A. oxyloba (DC.) Sch. Bip. and A. schurii Sch. Bip. are found in the Italian Peninsula, the Alps and the Carpathians. Phytogeographically, the finding of a species with such taxonomic connections in south-east Greece was unexpected. The new species grows in semi-shade, often hidden in suitable limestone rock hollows and the foot of rocks, together with several other Greek endemics. Its chromosome number of 2 n  = 18, counted in root tips, is also reported and illustrated.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 249–256.  相似文献   

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The phylogenetic relationships of the genera in the geometrid tribe Scopulini (Lepidoptera: Sterrhinae) were examined using 141 characters of adult morphology and ecology. The study material included 92 species, representing all previously recognized genera and covering the morphological variation and full geographical range of the tribe. The cladistic analysis resulted in 20 equally parsimonious trees and a strict consensus cladogram based on these was well resolved. A majority of the recovered synapomorphic characters have been used previously in the taxonomy of the tribe. However, many novel characters were found in the sclerotized structures of the thorax. Many previously recognized genera were found to be nonmonophyletic and based on the present revised, synapomorphy-based classification, the number of recovered genera is reduced considerably. Twenty new generic synonyms and 90 new or revived species combinations are proposed. Seven genera are considered valid, with the large genus Scopula Schrank including over 85% of all species in the tribe. The taxonomic history of the tribe is reviewed and the problems of earlier classifications are discussed. A key to the genera is presented, although an informal diagnosis is preferred. All recognized genera are illustrated and a revised world checklist of the Scopulini is presented.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 473−530.  相似文献   

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Based on herbarium and field observations, we confirm the generic delimitation of Holcoglossum and present a new infrageneric system for the genus. Our work supports Holcoglossum as a natural group including H. amesianum (Rchb.f.) Christenson and H. subulifolium (Rchb.f.) Christenson. The new infrageneric system of Holcoglossum includes two subgenera: Holcoglossum subgen. Brachycentron subgen. nov. and Holcoglossum subgen. Holcoglossum , the latter comprising two new sections, Holcoglossum sect. Holcoglossum and Holcoglossum sect. Sorotylos .  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 465–468.  相似文献   

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