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1.
Begonia gigabracteata H.Z. Li & H. Ma sp. nov. ( Begonia section Diploclinium , Begoniaceae) is described and illustrated from North Guangxi Zhuang Autonomous Region, south-west China. Its chromosome number (2 n  = 30) and pollen and seed micromorphology are reported. This species grows in ravines on damp or slightly moist limestone. It is morphologically similar to B. summoglabra T.T. Yü (section Reichenheimia ) and B. labordei H. Lél. (section Diploclinium ). However, it differs by its sparse glandular hairs, number of perianth segments, colour of venation on the abaxial blade, and unique heteromorphous bracts. A line drawing and plate of B. gigabracteata and a photograph of the type of B. summoglabra are presented as an aid to identification.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 83–90.  相似文献   

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Two new species of Sicyos from Mexico are described and illustrated: Sicyos cordifolius from the state of Guerrero, which belongs to the group with dry, armed fruits, and Sicyos bulbosus from the state of Oaxaca, which belongs to the group with fleshy, unarmed fruits. Sicyos cordifolius is quite different from the rest of the species previously described. Although S. bulbosus is very similar to S. galeottii Cogn., it is clearly different in receptacle shape and size.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 373–378.  相似文献   

4.
A new genus and species of osteoglossomorph fish is described from the Eocene Mahenge site in north central Tanzania. The new species is sympatric with the previously described osteoglossomorph † Singida jacksonoides , but is easily distinguished from it by the presence in the new species of teeth on the jaws and entopterygoid. The new species shares characters with the Heterotidinae, such as the two arms of the preopercle being of similar length and the posterior end of the maxilla lying on the dentary, and other characters with the Osteoglossinae (including † Phareodus ), for example the enlarged pectoral fin ray and the shape of the opercular bone. New specimens of † S. jacksonoides also have been recovered from the site, providing more information on the osteology of this fish. The relationships of these two Mahenge osteoglossomorphs are assessed, with both fishes placed within the Osteoglossidae, but of uncertain position in the family. Addition of the new species to previous cladistic data sets, and the revised information for † S. jacksonoides , causes the subfamily Osteoglossinae to be nonmonophyletic.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society, 2005, 144 , 213–228.  相似文献   

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Astragalus rahiminejadii , a new species endemic to Iran, is described and illustrated. This species, which belongs to section Astragalus , is confined to the western part of Iran (Prov. Kermanshah) and is known only from a single population. Seed testa morphology as viewed under the scanning electron microscope is discussed and photomicrographs are provided. In addition, the geographical distribution and ecology of the species belonging to this section are discussed.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 363–368.  相似文献   

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The primary purpose of this study was to determine whether morphological divergence has occurred in seeds of species in a subclade of Aristolochia subgenus Siphisia . Thus, we compared seed mass, surface area, and wings (presence or absence), embryo shape and state, and embryo length to seed length (E:S) ratio in A. californica Torr., endemic to California, A. macrophylla Lamk. and A. tomentosa Sims of eastern USA, and A. manshuriensis Komarov of eastern Asia. We also compared capsule length and number of seeds per capsule in the three US species. All four species have linear, underdeveloped embryos, but for the other morphological features statistically significant differences occurred among the taxa. However, none of the seed morphological features differed between the eastern North American species A. macrophylla and its eastern Asian sister species A. manshuriensis.   © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 433–436.  相似文献   

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Based on multivariate analyses, a new dioecious species of Poa from the Puneña and Altoandina phytogeographical provinces of Argentina is described. This species is most similar to Poa calchaquiensis of Poa section Dioicopoa . The ligule length, plant size, and glabrous pistillate anthoecia distinguish Poa nubensis . A key for identification and illustrations are also included.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 239–248.  相似文献   

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A new species Swartzia trimorphica Mansano & A. L. Souza (Leguminosae, Papilionoideae, Swartzieae) from the Amazonian Brazil, is described and illustrated. The new species is notable and distinct from all the other species of Swartzia by its highly unusual trimorphic stamens, while the other species have either an isomorphic or a dimorphic androecium. The new species is included in the section and subsection Swartzia , ser. Orthostylae based on its bracteolate pedicels, the cauligerous inflorescences, lateral style and the relative size of the ovary compared to the style. The atypically small gynoecium in the material suggests the possibility that flowers may be functionally unisexual. Field observations and more collections are needed to resolve this question.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 235–238.  相似文献   

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A palynological study of the genus Mentha L. (Lamiaceae)   总被引:1,自引:0,他引:1  
The pollen morphology and exine structure of 10 Mentha L . species were investigated using light microscopy and scanning electron microscopy. The pollen grains of all 11 species were hexazonocolpate with granular membranes and a circular amb, varying in shape from prolate-spheroidal to suboblate. Different colpus shapes were recognized in M . ×  dumetorum . The exine was bireticulate in section Pulegium , and reticulate in section Menthae . A correlation was found between pollen size and chromosome number. The results indicate that the pollen characters of the genus Mentha are valuable for taxonomic applications and may be useful for classification.  © 2008 Uludag University. Journal compilation © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 141–154.  相似文献   

10.
Fossil leaves and a branch with a leaf and a pod attached have been discovered from Ningming County, Guangxi Autonomous Region, China, and are described as Bauhinia larsenii sp. nov. (Leguminosae: Cercideae). The strata from which the Bauhinia fossils were collected, namely the Ningming Formation, were dated as Late Eocene–Oligocene based on a combination of pollen, fauna and flora. The affinity of the new species to Bauhinia section Micralvesia subsection Viridescentes species is also discussed.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 437–440.  相似文献   

11.
Until recently, all papillated specimens of Pareledone were ascribed to the species Pareledone charcoti (Joubin, 1905), of which P. aurorae (Berry, 1917) was considered a junior synonym. Re-examination of the papillated type material of Pareledone, coupled with extensive fishing over several years off the Antarctic Peninsula, has led to a revision of this position. Seven new species of papillated Pareledone are identified from the Antarctic Peninsula region. They are identified by subtle taxonomic characters, such as the morphology and placement of their papillae, although traditional indices often fail to separate the species. Whilst apparently sympatric, there is some evidence of niche separation of these species with respect to depth. A key is provided for their identification.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 75−108.  相似文献   

12.
Viola muliensis Y.S. Chen & Q.E. Yang, a new species of Viola L. (Violaceae) from Sichuan, China, is described and illustrated. Viola muliensis is endemic to Muli County, south-western Sichuan. This new species has yellow flowers with very short spurs and belongs to subsection Brevicalcaratae W. Beck., section Dischidium Ging. It is distinguished from other related species by having pedatipartite leaves.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 365–368.  相似文献   

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The species formerly recognized as Teucrium scorodonia in Madeira is here described as new: Teucrium francoi M. Seq., Capelo, J.C. Costa & R. Jardim. Morphologically close to species of Teucrium gr. scorodonia [ T. scorodonia L., T. pseudoscorodonia Desf., T. siculum (Raf.) Guss. and T. kotschyanum Poech], it exhibits, nonetheless, some distinct diagnostic characters. The indumentum density and type of hairs of T. francoi are clearly distinct from those of related species, as are the shape and dimensions of the leaves and bracts, calyx, and corolla, which are all taken as taxonomically significant diagnostic features. A diagnosis and a distribution map are presented for this new species. Morphology, ecology, biogeography, and conservation issues are discussed. Teucrium francoi , which is an endemic from Madeira (Portugal), is to be found mostly in the scope of the association Teucrio francoi–Origanetum virentis J.C. Costa, Capelo, Jardim, Sequeira, Lousã & Rivas-Martínez, but also occurs in somewhat humid habitats, such as open stands of Rosa mandonii Déségl. associated with small streams.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 639–647.  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   

18.
A new species of Betulaceae, Betula fujianensis , is described and illustrated from Luoboyan Reserve, Fujian Province, south-eastern China. Betula fujianensis is distributed in subtropical evergreen and deciduous broad-leaved mixed forest at elevations above 500 m, mostly as scattered individuals and occasionally as populations alone or with B. luminifera . Betula fujianensis belongs to section Betulaster and differs from other species in general morphology and phenology. A key to all species currently recognized in this section is presented, and the relationships between the new species and its closely related taxa are discussed.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 523–528.  相似文献   

19.
The indumentum of Piriqueta and Turnera is made up of nine different types of trichomes, which broadly can be divided into glandular and non-glandular. Taking into account foot shape, head size and pedicle size, five variants of glandular trichomes are recognized: microcrapitate, stipitate-capitate, sessile-capitate and setiform. The non-glandular trichomes can be simple (unicellular or pluricellular-uniseriate), stellate or porrect-stellate. The setiform glandular hairs are present in most species of Piriqueta . Simple unicellular hairs are the most widespread type, frequently being found in combination with other trichomes. Stellate trichomes show a restricted distribution in both genera. Within Piriqueta , section Africana has only simple trichomes, whereas section Piriqueta has also porrect-stellate trichomes; groups of species can be set up according to the presence and type of glandular trichomes. Within Turnera the stipitate-capitate trichomes are exclusive to series Papilliferae ; sessile-capitate trichomes are found in series Microphyllae , Annulares and in some species of Salicifoliae ; clavate trichomes are found only in series Turnera ; setiform glandular hairs are exclusive to T. collotricha , whereas the microcapitate trichomes are widely distributed.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 85–97.  相似文献   

20.
Calyptraeid gastropods are well know for the taxonomic difficulties caused by their simple, phenotypically variable shells. In this paper I demonstrate that what was previously considered to be a single species, Crepidula aculeata , is an ancient (3–15 Myr) cryptic species complex made up of at least eight species, and that this group should be placed in the genus Bostrycapulus . Despite the difficulty in finding diagnostic adult shell and anatomical features upon which species can be unambiguously identified, DNA sequences, protoconch morphology, embryonic morphology and developmental characters clearly differentiate these eight species. A single species with direct development and nurse eggs is present in the South Atlantic, and a species with planktotrophic development occurs in the equatorial Pacific. The species from Japan, Australia, Florida, the Pacific coasts of Mexico and Central America, and the Cape Verde Islands all have direct development. Most of these species are separated by > 15% divergence in COI sequence data. The fossil record of Bostrycapulus goes back to the Miocene, which agrees with genetic estimates of divergences within the genus ranging from 3 to 15 Mya. Surprisingly, these ancient species differ only slightly in morphology from each other and genetic differentiation does not correlate with geographical distance. I revise the genus Bostrycapulus on the basis of differences in adult morphology, embryonic morphology, mode of development, protoconch morphology, and DNA sequence data. I also describe four new species ( B. pritzkeri sp. nov., B. odites sp. nov., B. latebrus sp. nov. and B. urraca sp. nov. ) and remove three others ( B. gravispinosus , B. calyptraeformis , and B.  cf. tegulicius ) from synonymy with B. aculeatus .  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 75−101.  相似文献   

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