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1.
Gustavia johnclarkii and G. hubbardiorum, two new species from the wet forests of northwestern and Amazonian Ecuador, are described and illustrated. In addition, the two subspecies of both G. speciosa and G. macarenensis are elevated to species, and the new combination Gustavia paucisperma is provided. A justification for these changes is presented.  相似文献   

2.
One new name is proposed and eleven new combinations are made inCampomanesia andPimenta. Lectotypes are selected forC. eugenioides var.desertorum, C. phaea, andP. racemosa var.hispaniolensis, var.ouza, and var.terebinthina.  相似文献   

3.
George M. Diggs 《Brittonia》1986,38(4):344-351
Comarostaphylis spinulosa subsp.glandulifera is described from the mountains of Oaxaca and Puebla, Mexico. Four new combinations inComarostaphylis are also made:C. arbutoides subsp.costaricensis, C. discolor subsp.rupestris, C. polifolia subsp.minor, andC. spinulosa.Arctostaphylos glabrata, A. rupestris, andA. spinulosa are lectotypified and the status ofC. polifolia is discussed.  相似文献   

4.
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   

5.
Phylogenetic studies have demonstrated that Schefflera, the largest genus of Araliaceae, is grossly polyphyletic, comprising five distinct clades within the family. In an effort to establish monophyletic genera among the elements that currently comprise Schefflera, the genus Plerandra is expanded to encompass all of the members of one of these clades. In this synoptical revision, a new infrageneric classification is presented (along with a key) in which six subgenera are recognized. Four of these subgenera are newly described (Plerandra subgenera Canacoschefflera, Costatae, Gabriellarum, and Veilloniorum) and a fifth represents a new combination (Plerandra subg. Dizygotheca). A total of 33 species (one with two subspecies) are accepted, one of which is newly described (P. veilloniorum), and 22 new combinations are made (P. actinostigma, P. baillonii, P. cabalionii, P. costata, P. crassipes, P. elegantissima, P. elongata, P. emiliana, P. gabriellae, P. leptophylla, P. nono, P. osyana, P. osyana subsp. toto, P. pachyphylla, P. pancheri, P. plerandroides, P. polydactylis, P. reginae, P. seemanniana, P. tannae, P. vanuatua, P. veitchii). Neotypes are provided for six accepted names and one heterotypic synonym, and lectotypes are designated for 13 accepted names and 16 heterotypic synonyms. For each accepted species, full synonymy is provided along with geographic range and notes.  相似文献   

6.
We describe four new species of Cordia (Cordiaceae) from Brazil: Cordia fusca, C. glabrifolia, C. restingae, and C. tarodae. These are illustrated, and data on habitat, phenology, and distribution are provided.  相似文献   

7.
A new species of Acanthaceae (Ruellia saülensis) is described and illustrated from French Guiana, and three new combinations (Justicia potarensis, J. flaviflora, andJ. tobagensis) and one new name (Justicia coppenamensis) are proposed. The new species is compared to its closest relative (Ruellia rubra), and a justification of the transfers is provided.  相似文献   

8.
A new series,Passiflora ser.Carneae, and three new species are described inPassiflora subg.Astrophea:P. ascidia from Guyana and Venezuelan Guayana;P. balbis from Guyana, Venzuelan Guayana, and Amazonian Brazil; andP. saulensis from central French Guiana. A key to the 19 Guiana species ofPassiflora subg.Astrophea is provided.  相似文献   

9.

Key message

This study provides a mechanistic basis of the tolerance to light and water stress in two tropical tree species of the Malvaceae used for the reforestation in the tropics. G. ulmifolia is more sensitive to high irradiance than C. speciosa . Thus, C. speciosa is more appropriate for the reforestation of degraded areas with potential excess light or water deficit.

Abstract

Reforestation programs in tropics are necessary to mitigate the impacts of climate change, the preservation of biodiversity and for recovery of degraded areas. However, little is known about the abiotic stress tolerance of the major tropical tree species used in reforestation. This study was aimed at evaluating antioxidant defenses and photoprotective pigments against excess light and water deficit in Guazuma ulmifolia Lam. and Ceiba speciosa (A.St.-Hil) Ravenna. Plantlets of 6-month-old were exposed to progressive water deficit by withholding water under high and low irradiance growth conditions and then re-irrigated. G. ulmifolia leaves under high irradiance showed increased photo-oxidative damage, as indicated by a decreased Fv/Fm ratio and 5?12-fold increases in MDA levels, which correlated with a 14-fold increase in SOD activity, a 90 % decrease in POD activity and a 3?4-fold increases in hydrogen peroxide levels. Water deficit combined with high irradiance caused stronger chronic photoinhibition, indicating a synergistic effect that cannot be counterbalanced by antioxidant or photo-protective mechanisms. In contrast, to avoid photo-oxidative damage, C. speciosa enhanced SOD activity, maintained POD and CAT activities, and increased xanthophyll cycle pool size and DPS and β-carotene accumulation. These results indicate that G. ulmifolia is more sensitive to high irradiance than C. speciosa at early stages of development. Thus, C. speciosa is more appropriate for the reforestation of degraded areas with potential excess light or water deficit. In conclusion, this study provides a mechanistic basis of the tolerance abiotic stress in two tropical trees, thereby contributing for management strategies in reforestation projects.  相似文献   

10.
The following new taxa are recognized inArceuthobium: subgeneraArceuthobium andVaginata; sectionsVaginata, Campylopoda, andMinuta; seriesCampylopoda,Rubra, andStricta; speciesA. apachecum,A. californicum,A. guatemalense,A. hondurense, andA. pini; new formae spécialesA. abietinum f. sp.concoloris,A. abietinum f. sp.magnificae. New combinations:A. abietinum (Engelm.) Hawksworth & Wiens, andA. microcarpum (Engelm.) Hawksworth & Wiens.  相似文献   

11.
Paul A. Fryxell 《Brittonia》1971,23(3):231-237
Dendrosida, here described as new, comprises three taxa:D. batesii Fryxell,D. sharpiana (Miranda) Fryxell ssp.sharpiana, andD. sharpiana ssp.occidentalis Fryxell. The genus is interpreted as a primitive representative of the tribe Malveae, and its relationship to other genera of theAbutilon alliance is discussed. An analysis of mericarp morphology in relation to seed dissemination mechanisms indicates that theAbutilon alliance may be divided into an Abutiloid and a Sidoid group.Dendrosida is included in the latter.  相似文献   

12.
William R. Buck 《Brittonia》1983,35(4):327-330
Three new tropical American species ofSematophyllum are described with relatively broad leaves and short upper leaf cells:S. cubense, S. cataractae, andS. oedophysidium. The Central AmericaS. apaloblastum andS. barnesii are new combinations.Sematophyllum galipense, S. amnigenum, andS. cochleatum are briefly discussed.  相似文献   

13.
Two new monotypic genera are proposed:Karnataka, based uponSchultzia? benthamii C. B. Clarke (=K. benthamii) from southern Peninsular India andKedarnatha, based onK. sanctuarii, recently obtained from the Himalaya. Neither genus appears to be closely related to other apioid genera of our area.  相似文献   

14.
Steven R. Hill 《Brittonia》1980,32(4):464-483
The genusMalvastrum A. Gray is interpreted to include 22 taxa in 14 species. Seven taxa are here described as new, namely:M. americanum var.stellatum,M. tomentosum subsp.pautense,M. bicuspidatum subsp.campanulatum,M. bicuspidatum subsp.oaxacanum, M. bicuspidatum subsp.tumidum var.tumidum, M. bicuspidatum subsp.tumidum var.glabrum, andM. coromandelianum subsp.fryxellii. In addition, two new combinations are proposed, namely:M. tomentosum andM. coromandelianum subsp.capitato-spicatum.  相似文献   

15.
16.
Sucrea, a new genus of herbaceous bambusoid grasses is based on the newly described species,S. monophylla. Also belonging to this genus is another new species,S. maculata, and the taxon originally namedOlyra sampaiana. The new genus is contrasted in a key with others of its tribe Olyreae, and a key is given to its three species.  相似文献   

17.
The Neotropical genus Coussarea is species-rich and widely distributed but not well known. Seven new species are described here, documented mainly by recent botanical exploration: C. acrensis is found in western Brazil, C. boliviensis and C. mexiae in the mountains of northwestern Bolivia, and C. camposiana, C. maranonensis, C. pseudopilosula, and C. vasqueziana in Peru. The new combination C. insolita is based on Rudgea insolita from Colombia.  相似文献   

18.
Stuessya, a new genus from the Pacific slopes of southcentral Mexico is described. It is comprised of three species:S. apiculata, previously assigned to the genusViguiera;S. perennans, the generotype; andS. michoacana. The latter two taxa are previously undescribed. The genus is characterized by its urceolate, sclerified (at maturity) involucre. Chromosome counts of2n = 34 are reported forS. perennans. Relationships are problematical, but are reckoned to be somewhere betweenAldama andViguiera.  相似文献   

19.
Four new species of Ixora (Rubiaceae, Ixoreae) from Brazil are described and illustrated and their relationships to morphologically similar species as well as their conservation status are discussed. The new species, Ixora cabraliensis, Ixora emygdioi, Ixora grazielae, and Ixora pilosostyla are endemic to the Atlantic Forest of southern Bahia and Espirito Santo.  相似文献   

20.
During the systematic screening of active compounds from marine-derived fungi, the extract of a strain of Aspergillus versicolor MF359 isolated from a marine sponge of Hymeniacidon perleve was identified for detailed chemical investigation. Three new secondary metabolites, named hemiacetal sterigmatocystin (1), acyl-hemiacetal sterigmatocystin (2), and 5-methoxydihydrosterigmatocystin (3), together with a known compound, aversin (4), were characterized. 1 represents a first structure of sterigmatocystin hemiacetal from nature. The antibacterial activities of these identified compounds were evaluated against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeruginosa. Compound 3 showed activity against S. aureus and B. subtilis with MIC values of 12.5 and 3.125 μg/mL, respectively.  相似文献   

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