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1.
John H. Wiersema 《Brittonia》1996,48(4):520-531
Although all past floras of northern North America have recognized only one species of diminutive water-lily, actually two distinct species occur in the region. The circumboreal Nymphaea tetragona Georgi is largely confined to the northwestern part of the continent, extending as far east as Manitoba and occurring in the contiguous United States only in northwest Washington. A second species, N. leibergii Morong, is restricted to, but widely distributed in, northern North America, though it is absent from the extreme northwest. The two species are distinguishable from each other by several floral and foliar characters and the two species form a section, Nymphaea subg. Nymphaea sects. Chamaenymphaea, stat: nov. This is distinguished from the two other sections of subg. Nymphaea in a key, and Nymphaea subg. Nymphaea sect. Xanthantha, stat. nov., is proposed. Sect. Chamaenymphaea is described for North America, synonymy and nomenclature for both species are discussed, and a key including N. odorata Aiton is presented. A lectotype is provided for N. leibergii and the typification of N. tetragona is examined.  相似文献   

2.
Barbara Ertter 《Brittonia》1980,32(1):70-102
The genusOxytheca of western North America and temperate South America consists of seven species which are keyed, described, discussed, illustrated, and mapped. They are divided among sect.Oxytheca, sect.Acanthoscyphus stat. & comb. nov., and sect.Neoxytheca sect. nov.Oxytheca dendroidea subsp.chilensis is given as a new combination, whileO. parishii var.cienegensis andO. parishii var.goodmaniana are described as new. The history and relationships of the genus are discussed. It is retained as distinct fromEriogonum and is thought to have arisen from the larger genus nearE. spergulinum, E. parishii, andE. apiculatum in subgenusGanysma. Cytological data indicatedn= 20.  相似文献   

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The new species Serjania matogrossensis from Mato Grosso, Brazil, belonging to Serjania sect. Platycoccus, is described and illustrated. Serjania decemstriata is reinstated in Serjania sect. Platycoccus, and S. grammatophora (previously of doubtful origin) is identified as being of Brazilian origin. Fruits and tendrils of Lophostigma plumosum are described for the first time.  相似文献   

6.
Three new species of Mimosa are described: M. (sect. Batocaulon) epitropica Barneby & León de la Luz from Mexico (Baja California Sur); and two from planaltine Brazil, M. (sect. Habbasia) bispiculata Barneby and M. (sect. Mimosa) demissa Barneby. The affinity of each is discussed, and all are illustrated.  相似文献   

7.
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   

8.
Noel H. Holmgren 《Brittonia》1978,30(4):416-425
Penstemon goodrichii of sect.Cristati andP. navajoa andP. moriahensis of sect.Glabri are described, illustrated and mapped. Their relationships to kindred species are discussed.  相似文献   

9.
Two new species ofDioscorea,D. gentryi (subgen.Helmia sect.Monadelpha) andD. andromedusae (subgen.Helmia sect.Centrostemon) from Peru, are described and illustrated.  相似文献   

10.
Three new species of Mimosa sect. Mimosa ser. Mimosa subser. Polycephalae (Leguminosae, Mimosoideae) are described and illustrated. Mimosa canastrensis, Mimosa chrysothrix, and Mimosa decumbens are all from the campos rupestres of Minas Gerais, Brazil. Discussions about the distributions, habitat, and phenology of the species are provided, in addition to comparisons with similar taxa.  相似文献   

11.
Tetsuo Koyama 《Brittonia》1974,26(2):133-138
Described as new areSmilax biumbellata of the affinity ofS. nervomarginata,S. siamensis of the affinity of 5.perfoliata, and two others inSmilax sect.Macranthae:S. inversa andS. pachysandroides.Smilax inversa (characterized by strongly deflexed leaves and inflorescences on zigzag stems) andS. pachysandroides (with subsessile leaves on low simple stems) show no close resemblance to any previously known species of the section.  相似文献   

12.
Haplopappus linearifolius has been referred by various authors to the monotypic genusStenotopsis, to the genusStenotus, and withH. parrasanus toHaplopappus sect.Stenotopsis. A re-evaluation of the taxonomic affinities ofH. linearifolius based on morphological, chemical, and phenological evidence supports the hypothesis that it andEricameria cooperi are closely related and that these two species stand apart from others inEricameria. Accordingly, a section withinEricameria is established to accommodate them, and two new combinations are made,Ericameria sect.Stenotopsis andE. linearifolia. Also, a new subspecies,E. cooperi subsp.bajacalifornica is proposed.  相似文献   

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14.
Astragalus (sect.Argophylli subsect.Pseudargophylli)holmgreniorum, from the Virgin valley along the Utah-Arizona border, and A. (sect.Reventi-Arrecti subsect. Orcuttiani)ackermanii, from S Nevada, are described, figured and discussed.  相似文献   

15.
Mycopteris, a new genus of grammitid ferns, is described and combinations are made for the species that belong to it. Mycopteris is diagnosed by castaneous rhizome scales with turgid cells, usually pectinate laminae, blackish petioles and rachises, blackish pinna costae and veins, reddish setae, cretaceous hydathodes, glabrous sporangia, and the presence of Acrospermum ascomes. It is entirely neotropical, ranging from Mexico east into the West Indies and south to Bolivia. Mycopteris is one of two genera of grammitid ferns that are consistently associated with Acrospermum, an epibiotic ascomycete that produces black clavate fruiting bodies. Seventeen species of Mycopteris are recognized here, including one new species (M. longipilosa) and one elevated from the rank of variety to species (M. costaricensis). The following additional combinations are made here: M. alsopteris, M. amphidasyon, M. attenuatissima, M. cretata, M. grata, M. leucolepis, M. leucostica, M. longicaulis, M. pirrensis, M. praeceps, M. semihirsuta, M. steyermarkii, M. subtilis, M. taxifolia, and M. zeledoniana. Lectotypes are chosen for Ctenopteris leucosticta, Polypodium amphidasyon, and Polypodium pectinatum var. hispidum. For each accepted species, full synonymy and geographical range are provided. Taxonomic discussion is provided for species not widely recognized in previous treatments.  相似文献   

16.
Chamaecrista (sect.Apoucouita) aspidiifolia Irwin & Barneby from Bahia,Ch. (sect.Absus) glischrodes Irwin & Barneby from Minas Gerais andCh. (sect.Absus)didyma Irwin & Barneby from Brazilian Amazonia are described, figured, and discussed in terms of affinity. Several incidental new combinations inChamaecrista are proposed.  相似文献   

17.
Based on sequences from two single-copy nuclear genes (DMC1 and EF-G), four plastid genes (rbcL, rpoA, matK, and ndhF), and one mitochondrial gene (coxII), we investigate the origin of the H, St, W, and Y genomes in four allotetraploid species of Elymus and two allotetraploid species of Stenostachys. Despite significant incongruence between the two nuclear genes and between the nuclear and organelle data partitions, individual and combined analyses of the data partitions unequivocally show that the St and H genomes of the tetraploid American species of Elymus are derived from Pseudoroegneria and Hordeum, respectively, with Pseudoroegneria serving as the female parent, and that the H and W genomes of Stenostachys are derived from Hordeum and Australopyrum, respectively, with Hordeum serving as the female parent. The analyses equally clearly demonstrate that the St genome of the tetraploid Asiatic Elymus species is derived from Pseudoroegneria, with the latter serving as the female parent, but the relationship of the Y genome is less clear. Individual analyses of the nuclear genes provide conflicting results, but combined analysis of all data suggests a sister group relationship to Heteranthelium, albeit without any jackknife support.  相似文献   

18.
As presently known, the genusSiphonoglossa can be divided into two “subgenera,” one of which is here divided into two sections,Pentaloba andSiphonoglossa. Two new species are described from a locality in Durango, Mexico :S. durangensis in sect.Siphonoglossa andS. linearifolia in sect.Pentaloba. Three other species are transferred intoSiphonoglossa:S. canbyi from northeastern Mexico;S. buchii from Haiti and the Dominican Republic andS. incerta from southern Baja California, Mexico.  相似文献   

19.
Pedro Fiaschi 《Brittonia》2014,66(2):134-150
Three new species of Oxalis sect. Polymorphae are here described and illustrated: Oxalis artemioides, O. calcicola, and O. monochasiata. These species have narrow geographic distributions, each being known from just one location. Oxalis artemioides differs from other species of the section by the glabrous stem, narrow terminal leaflets (8–10.5 × 2 mm), and inflorescences with elongated dichasial branches bearing flowers only in the distal portion. Oxalis calcicola differs from other species by having the young stem with adpressed-retrorse trichomes, inflorescences shorter than adjacent leaves, short dichasial branches (0.5–3 mm long) with flowers densely grouped along the entire length, and glabrous pedicels. Oxalis monochasiata is remarkable because of its monochasial inflorescence and the two-ovulate carpels, both features unique within Oxalis sect. Polymorphae. The new species are compared to similar species of the section, and information on distribution and habitat, phenology, and conservation status according with IUCN criteria are provided. Geographic distribution maps, lists of examined materials and an identification key for species of this section are also presented.  相似文献   

20.
Two new monotypic genera,Didonica andUtleya, are described, withD. pendula from Panama andU. costaricensis from Costa Rica.Disterigma trimera (Panama),D. utleyorum (Costa Rica, Panama, Colombia, and Ecuador),Lateropora santafeensis (Panama),Lysiclesia panamensis (Panama),Macleania talamancensis (Costa Rica),Themistoclesia costaricensis (Costa Rica) andT. horquetensis (Panama),Vaccinium costaricense andV. orosiense (both from Costa Rica) and V.jefense (Panama) are all described as new. New combinations are provided for the PanamanianVaccinium floccosum (=Symphysia floccosa) and the West IndianVaccinium racemosum (=Symphysia racemosa). Keys are provided for the Central American species ofDisterigma andThemistoclesia, the species ofLateropora andLysiclesia, and the Costa Rican and Panamanian species ofVaccinium. Six new species are illustrated.  相似文献   

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