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1.
A new species of woody bamboo (Poaceae: Bambusoideae),Chusquea guirigayensis, is described and illustrated. This species is placed inChusquea sect.Swallenochloa (McClure) L. G. Clark because of its shrubby habit, short waxy internodes, intravaginal branching, and linearly arranged subsidiary buds/branches. In addition, we discuss related species, and describe the ecology and distribution of the new species. Separate keys based on sterile and fertile material of the Venezuelan species ofC. sect.Swallenochloa are provided.  相似文献   

2.
Lynn G. Clark 《Brittonia》1992,44(4):387-422
The 13 high altitude/latitude, dwarf species ofChusquea in Brazil are described, illustrated, and mapped, and their morphology, habitats, distributions, and taxonomic affinities are discussed. Two keys to species are provided, one based solely on vegetative characters, and the other on vegetative and flowering characters.Chusquea erecta, C. nutans, C. riosaltensis,C. windischii, C. caparaoensis, andC. nudiramea are described as new, andC. microphylla is elevated to specific status. Two subspecies are recognized within the variableC. mimosa: C. mimosa subsp.australis and subsp.mimosa. Seven species are formally classified withinChusquea sect.Swallenochloa; the remaining six species are classified into two informal categories, theNudiramea andHeterophylla groups. A list of all the species currently included withinChusquea sect.Swallenochloa is provided.  相似文献   

3.
Lynn G. Clark 《Brittonia》1996,48(2):250-262
Four new species ofChusqueaC. bahiana, C. bradei, C. leonardiorum, andC. loxensis—are described and illustrated.Chusquea bahiana andC. bradei, classified within subg.Rettbergia withinChusquea based on their infravaginal, geniculate branching and spatheate, often contracted inflorescences, are endemic to the Atlantic forests of Bahia and Espírito Santo, Brazil, where they are relatively uncommon.Chusquea leonardiorum andC. loxensis are native to the páramos of southern Ecuador;C. leonardiorum is moderately widespread, butC. loxensis is known from only two populations in the Parque Nacional Podocarpus in the province of Loja. These two species are allied withChusquea sect.Chusquea based on their erect to arching or scandent habit, extravaginal branching, and relatively numerous subsidiary branches per node.  相似文献   

4.
One new species of Chusquea and three of Swallenochloa are described. Morphological characters, especially of the culm leaves and branching, are pointed out as useful in distinguishing the two genera. A key to the 7 recognized species of Swallenochloa is given, and a discussion of its habitat, the páramo. Comment is made upon the recent evolution of the páramo habitat and therefore of the bamboo adapted to it, and reasons offered for the apparent active speciation which characterizes this bamboo genus.  相似文献   

5.
A new species, Salvia lagochila T. Wang & L. Wang sp. nov. (Lamiaceae) is described from Shangri‐La County in northwestern Yunnan, China. The diagnostic morphological characteristics in relation to closely similar species are discussed. Nutlet micro‐morphology was examined using scanning electron microscopy, and leaf anatomic structures were studied using light microscope. The new species is included in S. subgen. Salvia sect. Eurysphace subsect. Perennes on the basis of its perennial habit, entire upper floral lip and arcuate anther connectives.  相似文献   

6.
Chusquea is a diverse but monophyletic genus of Neotropical woody bamboos from primarily montane forests that comprises four well-supported lineages: subg. Magnifoliae, subg. Platonia, subg. Rettbergia, and the Euchusquea clade (comprising subg. Swallenochloa and subg. Chusquea). However, the relationships among clades or taxa within the Euchusquea clade inferred from molecular data are mostly not congruent with those inferred from morphological evidence, consequently limiting our ability to understand species relationships. In this study we generated foliar micromorphological and anatomical data for the Chusquea ramosissima informal group (Chusquea ramosissima, C. tenella, and C. tenuiglumis), and for the putative new species from Bolivia in this group, in order to test the value of these types of data for defining species and to seek potential synapomorphies for this group. Our results demonstrate that epidermal features, mainly with regard to the stomatal apparatus, proved to be more valuable in distinguishing species than anatomical characters. The presence of horizontally elongated silica cells over the veins and adaxial arm cells with invaginations from the abaxial side was shared by all the studied species but is not unique to this group. The type of trichomes, shape of silica bodies, type of arm cells, and midrib structure may be useful to lesser degree. All four species exhibited intraspecific variation in development of the papillae on the long cells. Support for the recognition of the new species from Bolivia is provided by micromorphological characters. An identification key based on leaf blade features is provided for the four studied species.  相似文献   

7.
A phylogenetic study of the Plantaginaceae   总被引:3,自引:0,他引:3  
In a study based on morphological, embryological and chemical data of the Plantaginaceae, within the subclass Sympetalae or Asteridae, the superorder Lamianae is shown to be monophyletic. However, it was not possible to reconstruct the phylogeny within Lamianae or to find a sister-group for the monophyletic Plantaginaceae – Hydrostachyaceae for the latter is rejected. Three or rarely four genera have previously been recognized within Plantaginaceae, but in both cases Plantago appears as polyphyletic, which is considered unacceptable. Six clades are recognized as subgenera within Plantago: subgen. Plantago (c. 131 species), subgen. Coronopus (c. 11 species), subgen. Littorella (three species), subgen. Psyllium (c. 16 species), subgen. Bougueria (one species), and subgen. Albicans (51 species). Within P. subgen. Plantago, the paraphyletic sect. Plantago (c. 42 species) is found in all parts of the world except South America, New Zealand, Australia, and New Guinea, where sect. Oliganthos and sect. Mesembryniae vicariate. It is not possible to infer the phylogeny within sect. Plantago, for example between the endemic species from distant Pacific Islands; their common ancestor might be a species that once had a very wide distribution. Keys to genera, subgenera, sections and series are given. Only one genus, Plantago L., is recognized. The following proposals are made in the Appendix: P. ser. Oliganthos Rahn, ser. nov.; P. ser. Carpophorae (Rahn) Rahn, stat. nov. (= sect. C.); P. ser. Microcalyx (Pilg.) Rahn, stat. nov. (= sect. M.); P. unibrackteata Rahn, nom. nov. (=P. uniflora Hook.f. non L.); P. subgen. Littorella (P. J. Bergius) Rahn, stat. nov. (=Littorella P. J. Bergius); P. araucana Rahn, nom. nov. (=Littorella australis Griseb. non Plantago australis Lam.); P. americana (Fernald) Rahn, comb. nov.(=Littorella a.); P. subgen. Bougueria (Decne.) Rahn, stat. nov. (=Bougueria Decne.); P. nubicola (Decne.) Rahn, comb. nov. (=Bougueria n. Decne.); P. subgen. Albicans Rahn, subgen. nov. Ten lectotypes are selected.  相似文献   

8.
Ants are widely recognized as ecologically important members of many low‐ to mid‐latitude ecosystems. Surprisingly, there is very little phylogeographical information on ants at regional scales. We examine here the phylogeography of two partially sympatric species of Trachymyrmex (Trachymyrmex septentrionalis and Trachymyrmex turrifex) ants in southeastern North America. We test the hypothesis that all Trachymyrmex species found in the USA expanded into North America from refugial populations located in northern Mexico as the post‐Pleistocene climate warmed. Phylogeographical theory predicts that these northward‐expanding species should exhibit higher genetic diversity in regions closer to Mexico and less diversity in more northern regions. We also examine, in the widely distributed T. septentrionalis, the hypothesis of vicariance that occurred at the formation of the Mississippi Embayment. Phylogeographical patterns indicate that T. septentrionalis has an eastern origin because diversity was highest east of the Mississippi, whereas T. turrifex probably has a Mexican origin because it lacked mitochondrial DNA (mtDNA) variation throughout its range and is currently absent from eastern North America. Both species are characterized by reduced haplotypic variation in the western coastal plain of the Gulf of Mexico (Texas and Louisiana), which may indicate recent expansion and/or bottlenecks associated with increased aridity and drought in these western regions. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 689–698.  相似文献   

9.
Phylogenetic relationships withinChusquea,a diverse genus of neotropical woody bamboos, and among selected members of the Bambusoideae were explored usingrpl16intron sequence data from the chloroplast genome. Mechanisms of mutation, including slipped-strand mispairing, secondary structure, minute inversions, and base substitutions, were examined within therpl16intron, and their effects on sequence alignment and phylogenetic analysis were investigated. Thirty-five bamboo sequences were generated and two separate matrices were analyzed using maximum parsimony. In the first, 23 sequences fromChusquea,1 ofNeurolepis,and 3 outgroups were included.Neurolepiswas supported as sister toChusquea, Chusqueawas strongly supported as a monophyletic lineage, and three species ofChusqueasubg.Rettbergiawere resolved as the most basal clade within the genus. In the second analysis, 15 sequences, 14 from across the subfamily and 1 outgroup, were included. A Bambusoideae clade was recovered with the Olyreae/Parianeae (herbaceous bamboos) and the Bambuseae (woody bamboos) each supported as monophyletic. Two clades corresponding to temperate and tropical woody bamboos were derived within the Bambuseae and the tropical taxa were further split into New World and Old World clades. Therpl16intron in bamboos was found to be susceptible to frequent length mutations of multiple origins, nonindependent character evolution, and regions of high mutability, all of which created difficulties in alignment and phylogenetic analysis; nonetheless therpl16intron is phylogenetically informative at the inter- and intrageneric levels in bamboos.  相似文献   

10.
Yvonne Widmer 《Biotropica》1998,30(3):400-415
The effect of canopy closure on spatial and morphological patterns of three understory Chusquea species was studied in pristine upper montane oak forests. Plots with either Chusquea talamancenis Widmer & L.G. Clark or C. tomentosa Widmer & L.G. Clark were set out in gaps, under intermediate tree canopy and under closed canopy. The third species Chusquea foliosa L.G. Clark was only found in gap and intermediate canopy sites in the study area. Clumps of all bamboo species tend to be few and large under open conditions and numerous and small under more shady conditions. The larger size of clumps in gaps is reflected in the number of culms per clump, the diameter of the culms and, as a consequence, clump basal area, clump crown area, and biomass (index of plant volume) compared to intermediate and closed canopy. The smaller clump density in gaps compared to closed canopy implies that there is more intraspecific competition and density dependent mortality (self-thinning effect) when a bamboo species is dominant under favourable light conditions. Parameters of performance like culm length, number of nodes per culm, number and length of primary branches, and number of branch nodes seem not to be affected by the light regime, unlike total number of branches, total branch length, and the branching pattern. Species differ in their response to the light environment: C. tomentosa and C. foliosa have a higher degree of morphological plasticity than C. talamancensis, which in turn, appears to be more shade tolerant. No difference between species has been found regarding their contribution to vegetation, parameters reflecting abundance per unit area (site clump area, site crown area and site index of clump volume) were similar for all three species.  相似文献   

11.
Aster saxicola W. P. Li & Z. Li, a new species of Asteraceae from southeastern Guizhou province, China, is described and illustrated based on morphological, molecular and cytological data. Morphological comparisons showed that A. saxicola is similar to A. oliganthus, but can be distinguished from the latter by its purple abaxial surface of the lower and middle cauline leaves, cordate‐ovate basal leaves with strigose hairs, outer three‐seriate phyllaries with purple or purplish apex, 9–14 ray florets and 10–18 disk florets. Phylogenetic analyses based on nrDNA ITS, ETS and plastid trnL–F DNA sequence data support that A. saxicola is a distinct species and belongs to Aster subgen. Aster sect. Ageratoides. Cytological observation shows that the new species is diploid with a karyotype formula 2n = 2x = 18 = 16m + 2sm. The new species should be considered endangered (EN) based on the IUCN red list criteria because of its restricted geographic range.  相似文献   

12.
Cousinia brevicaulis is described and illustrated as a new species from eastern Iran. This species belongs to the C. sect. Lasiandra Bunge as defined by hairy anther tube, yellow, pale yellow or rarely milky flowers, monocarpic growth form and corymbose branching of stem. It is easily distinguished from other species of the section by its very short‐stemmed habit. The new species is distributed in the same region as other species of C. sect. Lasiandra.  相似文献   

13.
A new species of Lysimachia (Primulaceae), L. huchimingii G. Hao & H. F. Yan from China is described and illustrated. It is morphologically compared to its most closely related species in Lysimachia subgen. Lysimachia sect. Nummularia ser. Paridiformes.  相似文献   

14.
梾木属四照花亚属的系统和总览   总被引:3,自引:0,他引:3  
向秋云 《植物研究》1987,7(2):33-52
不同作者对四照花亚属的性状估价不同,因而对其下分类群的分类很不一致。本文据其不同的过冬习性和芽结构与地理分布相关联,建立了两个组、两个系的新系统。并根据"形态地理"学的方法,认为"种"是一组居群,与另一种在形态上需有间断区别,"亚种"是种的组成成分,有一定分布区(若是同域则占居不同生境),形态上有区别,但在分布区交接处有中间类型存在,"变种"是种内限于较狭分布区域成分散分布的变异类形;将该亚属由原来19个种处理成4个种,12个亚种及3个变种。  相似文献   

15.
16.
Aim The plant genus Bursera, with 104 species of trees and shrubs, has been used as a model for biogeographical analyses because of its high species richness and large number of endemic species. The biogeographical patterns of Bursera and their implications for its phylogenetic classification are reviewed in order that some hypotheses on the historical biogeography of tropical Mexico can be proposed. Location Bursera is found in the south‐western USA, most of Mexico, mainly below 1700 m elevation in tropical forests, with some species in xeric shrublands, diversifying along the Pacific slope, Central America, and north‐western South America. A few species occur on the Galapagos and Revillagigedo archipelagos, some of which are endemics, whereas in the Antilles species are distributed extensively, with several endemics in the Bahamas, Cuba, Jamaica, and Hispaniola. Methods Data from specimens in herbaria and the literature were used to construct a matrix of 104 species in 160 areas. Distributional patterns of the species of Bursera were inferred applying track analysis, parsimony analysis of endemicity (PAE), and Brooks parsimony analysis (BPA). Results Track analysis revealed four individual tracks: (1) a circum‐Caribbean track, comprising species of the Bursera simaruba species group; (2) an Antillean track, including species that have been transferred to Commiphora based on their pollen traits; (3) a Mexican Pacific track, including species of the B. fragilis, B. microphylla, and B. fagaroides species groups, called ‘cuajiotes’; and (4) a Neotropical Pacific track, including the two species groups assigned to section Bullockia, in which the individual track of the Bursera copallifera species group is nested within the track of the B. glabrifolia species group. The four tracks overlap in a node in the Mexican Pacific slope, where they are highly diversified. PAE allowed us to identify 22 areas of endemism: 12 in Mexico (11 along the Mexican Pacific slope), six in the Antilles, two in Central America, one in South America, and one in the Galapagos. The general area cladogram obtained by BPA has two main clades: one includes the greater Antilles; and the other, 12 Mexican areas of endemism. Main conclusions Bursera fragilis, B. microphylla, and B. fagaroides species groups can be treated together as a new section within Bursera, sect. Quaxiotea, because they are segregated from the other groups of sect. Bursera based on morphological, anatomical, molecular and geographical evidence.  相似文献   

17.
Passiflora boticarioana, a new species of subgen.Passiflora, supersect.Stipulata, sect.Dysosmia, from the state of Minas Gerais, Brazil, is described, illustrated, and compared with morphologically similar species.  相似文献   

18.
八角属植物分类   总被引:13,自引:4,他引:9  
林祁 《植物研究》2001,21(2):161-174
根据对18个国家和地区121个标本馆收藏的万余份八角属植物标本研究,结合在国内8个省区野外调查、采集、引种和对生长发育与物侯的观察,本文对世界性八角属植物做了分类学修订。根据花蕾和花被片形态特征的变异,将八角属分为2组:八角组-含9种1亚种,其花蕾卵球形,花被片长圆形、椭圆形、披针形至狭舌状,扁平;八角茴香组-含25种2亚种1变种,其花蕾球形,花被片宽卵形至圆形,下凹。将凹脉组作为八角组的新异名,圆被亚属作为八角茴香组的新异名;指定了红茴香和柬埔寨八角的后选模式。本文还分析了八角属植物的分类学性状,作出有分类检索表,提供有各种植物的地理分布资料,列举出查阅的主要标本,并对各分类单元均作了分类学注释。  相似文献   

19.
八角属植物分类   总被引:6,自引:1,他引:5  
林祁 《植物研究》2001,21(3):321-334
根据对18 个国家和地区121 个标本馆收藏的万余份八角属植物标本研究, 结合在国内8 个省区野外调查、采集、引种和对生长发育与物侯的观察, 本文对世界性八角属植物做了分类学修订。根据花蕾和花被片形态特征的变异, 将八角属分为2 组:八角组-含9 种1 亚种, 其花蕾卵球形, 花被片长圆形、椭圆形、披针形至狭舌状, 扁平;八角茴香组-含25 种2 亚种1 变种, 其花蕾球形, 花被片宽卵形至圆形, 下凹。将凹脉组作为八角组的新异名, 圆被亚属作为八角茴香组的新异名;指定了红茴香和柬埔寨八角的后选模式。本文还分析了八角属植物的分类学性状, 作出有分类检索表, 提供有各种植物的地理分布资料, 列举出查阅的主要标本, 并对各分类单元均作了分类学注释。  相似文献   

20.
A new Vietnamese species of the genus Camellia L. (Theaceae, Theoidae) is described and illustrated as C. luteocerata Orel. This species occurs in the rainforests of Lam Dong Province, Vietnam. Morphological characteristics that distinguish it from related Camellia species are presented and discussed. Morphological evidence supports a taxonomic placement in a new section, which is described here as Camellia sect. Dalatia Orel, within C. subgen. Protocamellia (sensu Chang).  相似文献   

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