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1.
Evidence from the chloroplast trn T-L spacer, trn L intron and trn L-F spacer shows the subtribe Glossonematinae of the tribe Asclepiadeae, hitherto composed of the Arabian and North African genera Glossonema , Odontanthera and Solenostemma , not to be monophyletic. While the affinities of Solenostemma cannot be determined with certainty at present, molecular, karyological and morphological evidence suggests that Glossonema and Odontanthera are closely allied to Pentarrhinum , an African genus of five species, belonging to the Cynanchinae.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 145–158.  相似文献   

2.
As a result of recent fieldwork in north-east Morocco, a new woody Malvaceae species, Lavatera valdesii Molero & J.M. Monts., is described here. The morphological characters that link it to other species in Sect. Olbia (Medik.) DC. are discussed, as are those traditionally used in defining the species that make up this section. A recently described species of this group, Lavatera plazzae Atzei, is established here as a synonym of L. stenopetala Coss. & Durieu ex Batt., a species previously considered as an endemic of east Algeria. On the basis of morphological characters, we propose the exclusion of both L. thuringiaca and L. cashmiriana Cambess. from Sect. Olbia.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 445–454.  相似文献   

3.
4.
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   

5.
Phylogenetic relationships are inferred from nuclear ribosomal internal transcribed spacer sequences for species belonging to Sophora sect. Edwardsia from South America, New Zealand, Lord Howe Island, Hawai'i, La Réunion, Easter Island, and Raivavae Island (French Polynesia). Results support the monophyly of sect. Edwardsia , but relationships among the species from this section are poorly resolved due to most species having identical sequences. The origin of Sophora sect. Edwardsia is discussed, as competing hypotheses have proposed the group originated in South America from a North American ancestor, or in the north-west Pacific. We suggest sect. Edwardsia may have arisen in the north-west Pacific from a Eurasian ancestor.  © The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 435–441.  相似文献   

6.
Asteriscus Mill. is a genus belonging to the Inula -group of the Asteraceae-Inuleae. It is here delimited to contain three species, A. maritimus (L.) Less., A. hierochunticus (Michon) Wikl. (generally known as A. pygmaeus (DC.) Coss & Dur.) and A. spinosus (L.) Sch. Bip. (generally known as Pallenis spinosa (L.) Cass.), growing largely in the Mediterranean and N African regions. The morphology, phytogeography, phylogeny and systematic position of all three species are discussed and a cladogram of the genus is presented.  相似文献   

7.
Morphologically intermediate plants between Weigela hortensis (Siebold & Zucc.) K.Koch and W. maximowiczii (S.Moore) Rehder have been found in Miyagi and Yamagata Pref., northern Japan. Quantitative character analyses of flowers, pollen stainability and molecular analyses indicated that the intermediate plants were hybrids of those two species. This is the first record of an intersectional hybrid with W. maximowiczii (sect. Weigelastrum ) as one of the parent species. The morphological differences among hybrid individuals imply the possibility of backcrosses or formation of second or later generations of hybrids, although those may be quite rare because of a low frequency of viable pollen grains. Causes of hybridization between two distantly-related species in Weigela are discussed. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 138 , 369–380.  相似文献   

8.
Two morphotypes of bracken fern in the genus Pteridium Gled. ex Scop. occur in sub-Saharan Africa. The more common and widespread of these is assigned in contemporary systematic treatments to the European subspecies, P. aquilinum (L.) Kuhn ssp. aquilinum . We show that this African form is separable morphometrically and genomically from the European subspecies, and reinstate its earlier name P. aquilinum ssp. capense (Thunb.) C.Chr. The second African bracken, with a more localized tropical distribution mainly in the drainage basins of the Congo and Zambezi River systems, is confirmed as P. aquilinum ssp. centrali-africanum Hieron. ex R.E. Fr. We reject suggestions that this taxon be treated as a full species. Phenetic cluster analysis based on use of Arbitrarily Primed Polymerase Chain Reaction (A-P PCR) and Inter Simple Sequence Repeat (ISSR) fingerprinting of the nuclear genome provides evidence that the two African brackens are more closely related to each other than to other taxa, and sister to a grouping of the European sspp. aquilinum and pinetorum . The two African subspecies share solely with ssp. aquilinum a distinctive chloroplast haplotype carrying a 5-base direct repeat in the rps 4 –trn S region, confirming the close phyletic relationship between sspp. aquilinum , capense and centrali-africanum .  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 311–321.  相似文献   

9.
Molecular variation in Antitrichia curtipendula (Hedw.) Brid. s.l. was studied based on the nuclear internal transcribed spacer (ITS) and the chloroplast markers trn L- trn F and rpl 16, and analysed by neighbour joining (for ITS; recombination present), maximum parsimony (chloroplast markers) and TCS (haplotype network). Old World plus E North American populations belong to a different lineage than those of W North America. These are molecularly well differentiated and are treated as A. curtipendula and A. gigantea (Sull. & Lesq.) Kindb. Two distinct groups of Old World haplotypes are separated by one 'missing' haplotype and are interpreted as cryptic species. Tropical African populations share one ITS deletion and form a lineage within one of the cryptic species. Molecular variation within A. gigantea , within each of the two cryptic Old World plus E North American (except tropical African) haplotype groups, and among tropical African populations are of similar magnitude, suggesting that analogous mechanisms and similar time spans explain the found variation. Events related to Pleistocene climatic oscillations are suggested as having caused this differentiation within each group, whereas the African lineage was probably split off before this. Identical tRNA-Gly sequences were found in 33 specimens; new primers were designed for rpl 16 and ITS 1+2.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 341–354.  相似文献   

10.
Sophora tomentosa , the type species of the genus Sophora , is shown by phylogenetic analyses of rbc L and ITS sequence data to be sister to Sophora sect. Edwardsia . S. tomentosa and most of the species from sect. Edwardsia share hypogeal germination, exstipulate leaves, and terete filaments. These species have buoyant seeds, and are distributed by ocean currents throughout the pantropics ( S. tomentosa ) and around southern temperate oceanic islands (sect. Edwardsia ). S. tomentosa differs from the species of sect. Edwardsia by its frutescent growth habit, terminal elongate inflorescence and smooth-walled legume. S. macrocarpa is unusual in sect. Edwardsia as its leaves have stipules, the filaments are winged, and the legume is smooth-walled.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 439–446.  相似文献   

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