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1.
We analyze the latitudinal shift in the onset of synchronous flowering in the woody genera Montanoa and Simsia (Asteraceae) between Mexico (28° N) and the Equator, where it cannot be caused by declining day length. Synchronous flowering of >100 Montanoa quadrangularis trees was observed during two consecutive years near Cali, Colombia (4° N). Analysis of herbarium specimens yielded flowering periods for 21 Montanoa species and 18 Simsia species between 4 and 28° N. Daily insolation is a function of day length and the angle at which the sun’s rays strike the earth. Between Mexico and Colombia (4° N), the maximum of insolation gradually shifts from the summer solstice to the autumn equinox. In parallel, flowering of Montanoa and Simsia starts progressively later between July and November, during the period of declining insolation. Near the Equator, there are two periods of declining insolation, and correspondingly, two flowering periods. Thus, at all tropical latitudes, flowering time of Montanoa and Simsia is highly correlated with declining insolation. The seasonal decline in daily insolation, rather than in photoperiod, apparently induces synchronous flowering of Montanoa and Simsia at the same time each year.  相似文献   

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New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.  相似文献   

4.
 A new species of Erysiphe sect. Uncinula is described and illustrated from Patagonia, Argentina. Erysiphe patagoniaca sp. nov., found on leaves of Nothofagus × antarctica, is similar to E. nothofagi and E. kenjiana, but differs in its appendages being twisted throughout their length and the number of appendages, asci, and ascospores. The two endemic species of Erysiphe sect. Uncinula, E. magellanica and E. nothofagi, coexisted on the same leaves together with Erysiphe patagoniaca. Received: September 19, 2002 / Accepted: November 28, 2002 Acknowledgments The authors are grateful to Ms. Seiko Niinomi for providing the micrographs of ascomata of Erysiphe spp. on Nothofagus. Correspondence to:S. Takamatsu  相似文献   

5.
Petra Hoffmann 《Brittonia》2008,60(2):136-166
Heterosavia (Phyllanthaceae) is segregated from Savia (tribe Bridelieae), recognized at generic rank, and placed in tribe Phyllantheae. Floral, fruit, leaf anatomical, leaf venation, and pollen characters of the neotropical taxa previously united as Savia including Gonatogyne are discussed and illustrated. Keys to the three genera and to the species of Heterosavia are presented. Four species (all new combinations), Heterosavia bahamensis, H. erythroxyloides, H. laurifolia, and H. maculata, are recognized. The new combinations Heterosavia laurifolia var. intermedia and H. maculata var. clementis are proposed. The names Heterosavia, H. erythroxyloides, H. laurifolia, Savia clementis, S. clusiifolia, S. clusiifolia var. fallax, and S. longipes are lectotypified. Distribution maps and conservation assessments (IUCN ratings) of Heterosavia species and varieties are provided.  相似文献   

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Two new species, Elaphoglossum alvaradoanum and E. pendulum, are described. The first species is endemic to Cocos Island, and the second to the mountains of Costa Rica. Elaphoglossum auripilum var. longipilosum is elevated to species rank as E. longipilosum.  相似文献   

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A novel cytoplasmic male sterility (CMS) was identified in Brassica juncea, named as hau CMS (00-6-102A). Subsequently, the male sterility was transferred to B. napus by interspecific hybridization. The hau CMS has stable male sterility. Flowers on the A line are absolutely male sterile, and seeds harvested from the line following pollinations with the maintainer gave rise to 100% sterile progeny. The anthers in CMS plants are replaced by thickened petal-like structures and pollen grains were not detected. In contrast, in other CMS systems viz. pol, nap, tour, and ogu, anthers are formed but do not produce viable pollen. The sterility of hau CMS initiates at the stage of stamen primordium polarization, which is much earlier compared with the other four CMS systems. We have successfully transferred hau CMS from B. juncea to B. napus. Restorer lines for pol, ogu, nap, and tour CMS systems were found to be ineffective to restore fertility in hau CMS. Sixteen out of 40 combinations of mitochondrial probe/enzyme used for RFLP analysis distinguished the hau CMS system from the other four systems. Among these sixteen combinations, five ones alone could distinguish the five CMS systems from each other. The evidence from genetic, morphological, cytological and molecular studies confirmed that the hau CMS system is a novel CMS system. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

9.
Three new hermaphrodite species of Ocotea (Lauraceae) from the campos rupestres of Brazil are described and illustrated: Ocotea pumila, which is known from Bahia state; and Ocotea colophanthera and Ocotea rupestris both from Minas Gerais state. Their diagnostic features are pointed out, and a discussion of their relationships to other species of Ocotea is provided.  相似文献   

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Umbelopsis gibberispora is described as a new species in the genus Umbelopsis, Umbelopsidaceae, Mucorales. The species differs from others in this genus by ellipsoidal sporangiospores with unilaterally thickened walls. Phylogenetic analyses based on nuclear large subunit ribosomal DNA (nLSU rDNA) partial sequences suggest that U. gibberispora, U. swartii, and U. westeae form a clade together with the strains of Umbelopsis ramanniana. The ex-type strain of Micromucor ramannianus var. angulisporus is found to be very close to Umbelopsis vinacea, whereas other isolates identified under the former name in the sense of Linnemann fall in the U. ramanniana subclade. For these isolates, a new species, Umbelopsis angularis, is introduced. Phylogenetic relationships among Umbelopsis species are discussed related to their attributes of the sporangial wall and mature spore shapes. Received: August 27, 2002 / Accepted: March 11, 2003 Acknowledgments We thank Dr. Takashi Ohsono, Graduate School of Agriculture, Kyoto University, Japan, for providing the strain of U. gibberispora (CBS 109328). We also thank Dr. Wieland Meyer, University of Sydney, Australia for access to the phylogenetic tree based on ITS sequence data before publishing, and Dr. Richard C. Summerbell, Centraalbureau von Schimmelcultures, the Netherlands, for linguistic corrections.  相似文献   

12.
Summary  A taxonomic revision of the palm genus Podococcus (Arecaceae) is presented. Two species are recognised: P. barteri, a species relatively widespread in a coastal band from Nigeria to the D. R. Congo and P. acaulis, a species previously considered conspecific to P. barteri, almost exclusively confined to Gabon. The taxonomic history, morphology, distribution and conservation status of the genus and each species are discussed  相似文献   

13.
P transposons belong to the eukaryotic DNA transposons, which are transposed by a cut and paste mechanism using a P-element-coded transposase. They have been detected in Drosophila, and reside as single copies and stable homologous sequences in many vertebrate species. We present the P elements Pcin1, Pcin2 and Pcin3 from Ciona intestinalis, a species of the most primitive chordates, and compare them with those from Ciona savignyi. They showed typical DNA transposon structures, namely terminal inverted repeats and target site duplications. The coding region of Pcin1 consisted of 13 small exons that could be translated into a P-transposon-homologous protein. C. intestinalis and C. savignyi displayed nearly the same phenotype. However, their P elements were highly divergent and the assumed P transposase from C. intestinalis was more closely related to the transposase from Drosophila melanogaster than to the transposase of C. savignyi. The present study showed that P elements with typical features of transposable DNA elements may be found already at the base of the chordate lineage. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

14.
Eschweilera awaensis and Grias subbullata, two new species known from the wet forests of northwestern Ecuador, are described. Eschweilera awaensis occurs in Esmeraldas, Los Ríos, and the westernmost parts of the Pichincha provinces between 25–650 m elevation. Grias subbullata, is known only from two localities in the Santo Domingo de los Tsáchilas province between 900–1670 m elevation. The new species are illustrated and their relationships with similar species are discussed.  相似文献   

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One new species each is proposed in Chalybea and Huilaea (Melastomataceae: Blakeeae). Chalybea peruviana has elliptic, 5-plinerved leaves with entire, revolute margins, inflorescences with 33–39 flowers, and is endemic to Peru. Huilaea calyptrata has inflorescences with 15–17, irregularly calyptrate flowers, anthers with a warty connective in the shape of an inverted hand fan, and is endemic to Ecuador. A key to the eight species of Huilaea is provided.  相似文献   

16.
Polygala pauciramosa, a new species from the Federal District and the state of Goiás is described, illustrated, and compared with related species of Polygala subgenus Hebeclada. The new species is an herb that grows in seasonally to permanently wet savannas. A key to the species of Polygala subgenus Hebeclada from Goiás state, Brazil is provided.  相似文献   

17.
Ogataea parapolymorpha sp. n. (NRRL YB-1982, CBS 12304, type strain), the ascosporic state of Candida parapolymorpha, is described. The species appears homothallic, assimilates methanol as is typical of most Ogataea species and forms hat-shaped ascospores in asci that become deliquescent. O. parapolymorpha is closely related to Ogataea angusta and Ogataea polymorpha. The three species can be resolved from gene sequence analyses but are unresolved from fermentation and growth reactions that are typically used for yeast identification. On the basis of multiple isolates, O. angusta is known only from California, USA, in association with Drosophila and Aulacigaster flies, O. parapolymorpha is predominantly associated with insect frass from trees in the eastern USA but O. polymorpha has been isolated from various substrates in the USA, Brazil, Spain and Costa Rica.  相似文献   

18.
Summary  New combinations are provided for nine taxa in the Bolivian Compositae — four in Dendrophorbium (Senecioneae), four in Vernonia (Vernonieae) and one in Viguiera (Heliantheae) — in advance of an on-line publication of a ‘Preliminary checklist of the Compositae of Bolivia’.  相似文献   

19.
Alansmia, a new genus of grammitid ferns is described and combinations are made for the 26 species known to belong to it. Alansmia is supported by five morphological synapomorphies: setae present on the rhizomes, cells of the rhizome scales turgid, both surfaces of the rhizome scales ciliate, laminae membranaceous, and sporangial capsules setose. Other diagnostic characters include pendent fronds with indeterminate growth, concolorous, orange to castaneous rhizome scales with ciliate or sometimes glandular margins, hydathodes often cretaceous, and setae simple, paired or stellate. The group also exhibits the uncommon characteristic of producing both trilete and apparently monolete spores, sometimes on the same plant. New combinations are made for Alansmia alfaroi, A. bradeana, A. canescens, A. concinna, A. contacta, A. cultrata, A. dependens, A. diaphana, A. elastica, A. glandulifera, A. heteromorpha, A. immixta, A. kirkii, A. lanigera, A. laxa, A. longa, A. monosora, A. reclinata, A. semilunaris, A. senilis, A. smithii, A. spathulata, A. stella var. stella, A. stella var. flava, A. turrialbae, A. variabilis, A. xanthotrichia. Lectotypifications are made for Alansmia concina, A. variabilis, Polypodium ciliare, P. flexile, and P. ovalescens. The genus is named in honor of pteridologist Alan R. Smith.  相似文献   

20.
A new species in Croton section Argyroglossum from northeastern Brazil is described and illustrated. Croton limae was previously confused with C. tricolor and C. argyrophyllus, which are the most closely related species. Its geographic distribution is discussed and a key to distinguish these three related species is presented.  相似文献   

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