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1.
Timothy Plowman 《Brittonia》1986,38(3):189-200
Erythroxylum simonis, E. pauferrense, E. bezerrae, andE. tianguanum from northeastern Brazil are described and illustrated, and their taxonomic and phytogeographic relationships are discussed.  相似文献   

2.
A new alkaloid identified as 3β,6β-ditigloyloxynortropane as 3β,7β-ditigloyloxynortropane, 4-hydroxyhygrinic acid, methylecgonidine and tropacocaine have been isolated from the leaves of Erythroxylum argentinum. The new structure was established by means of spectroscopic techniques. Four other species E. deciduum, E. microphyllum, E. pelleterianum and E. cuneifolium collected in the state of Rio Grande do Sul were screened for methylecgonidine and tropacocaine by CG/MS. Two of these plants contain tropacocaine and two contain methylecgonidine. GC/MS analysis of all 5 species for cocaine proved fruitless. The chemotaxonomic significance of these results is discussed.  相似文献   

3.
A new species of Sinningia (Gesneriaceae) from northeastern Brazil   总被引:1,自引:0,他引:1  
Sinningia nordestina is described and illustrated. Morphological and molecular characters are discussed. It is a new species endemic to northeastern Brazil and is distinguished from other members of the genus by its vestigial tubers, ascending pedicels with pendent flowers, small corollas, and deviating flowering period.  相似文献   

4.
Erythroxylum coca is a distylous species with a strong self-incompatibility system linked with the floral dimorphism. The two sets of stamens in the flowers are usually unequal in length, but between individuals of both morphs there is considerable variation in the relative qengths of the two sets of stamens, which is unrelated to the incompatibility system. Pin flowers produce more pollen grains than thrum flowers, but thrum pollen is larger than pin pollen. Within each morph the two sets of stamens produce pollen grains of slightly different diameter. Erythroxylum novogranatewe is also distylous. Pin flowers of E. novogranatense var. novogranatense are partially self-compatible, while thrum flowers of E. novogranatense var. truxillense are self-incompatible. Reports of tristyly and of four different morphs in species of Erythroxylum are probably misinterpretations, resulting from limited sampling, of the continuous variation in the relative lengths of the two sets of stamens.  相似文献   

5.
A new tropane alkaloid, named the 7β-acetoxy-3β,6β-dibenzoyloxytropane (1), was isolated from a methanol extract of Erythroxylum rimosum O.E. Schulz leaves. Other known compounds were detected, including quercetin, kaempferol-3-O-α-l-arabinofuranoside, (+)-catechin, epicatechin, quercetin-3-O-α-arabinofuranoside, quercetin-3-O-α-arabinopyranoside, quercetin-3-O-β-arabinopyranoside, quercetin-3-β-glucopyranoside, kaempferol, quercetin-3-O-β-galactopyranoside, β-sitosterol, α-amyrin, β-amyrin, and the ester derivatives of these two amyrins. Compound 1 exhibited weak inhibition of acetylcholinesterase. Structural identification was performed using IR, ESIHRMS and one- and two-dimensional NMR data analyses and confirmed by comparison with literature data.  相似文献   

6.
Timothy Plowman 《Brittonia》1988,40(3):256-268
Erythroxylum foetidum Plowman,E. guanchezii Plowman, andE. macrophyllum Cav. var.savannarum Plowman are described and illustrated, and their taxonomic and phytogeographic relationships are discussed.  相似文献   

7.
Solanum jabrense is apparently rare, and is only known from few collections in the Pico do Jabre of the state of Paraíba, Brazil. It is illustrated and its affinities with the informalErythrotrichum group are discussed.  相似文献   

8.
Miconia caiuia occurs only in the highly endangered submontane moist forests in the states of Alagoas, Pernambuco, and northern Bahia, Brazil. It belongs to Miconia section Miconia subsection Secundiflorae. This new species can be distinguished from other species in this subsection by the lepidote-stellate trichomes on young branches, petioles, inflorescences and hypanthia, leaves with suprabasal nerves and wrinkled/auriculate bases, abaxial leaf surfaces with only sparse trichomes, a 5-locular ovary, and large mature fruits (10–13?×?12–15 mm) with up to 15 seeds, which are 2.5–3.5 mm long.  相似文献   

9.
A list is provided of all 358 taxa ofErythroxylum described from the Neotropics through the year 2000, including type specimen citations, probable synonymy, geographic distribution, and designation of 41 new lectotypes and one new neotype. The list includes 187 accepted species, eight accepted varieties, 27 infraspecific names of uncertain status, and 136 synonyms. A searchable specimen database and type image archive may be accessed at www.fieldmuseum.org/research_collections/database.htm. T. Plowman, deceased 7 January 1989.  相似文献   

10.
Timothy Plowman 《Brittonia》1982,34(4):442-457
Erythroxylum steyermarkii Plowman,E. undulatum Plowman andE. williamsii Standley ex Plowman, all known only from Venezuela, are described and illustrated, and their taxonomic and phytogeographic relationships are discussed.  相似文献   

11.
Six tropane alkaloids were isolated from the Sri Lankan endemic plant Erythroxylum zeylanicum O.E. Schulz (Erythroxylaceae) and structurally elucidated by NMR and MS measurements. Three of them, erythrozeylanines A [1R,3R,5S,6R-6-acetoxy-3-(3',4',5'-trimethoxybenzoyloxy)tropane], B [cis-3 beta-(cinnamoyloxy)tropane], and C [cis-6 beta-acetoxy-3 alpha-(cinnamoyloxy)tropane] are new, whereas the others have already been found in other Erythroxylum species. For the first time, the absolute configuration of a tropane alkaloid (erythrozeylanine A) has been determined by quantum chemical CD calculations.  相似文献   

12.
In this paper we present new synonyms and typifications in Erythroxylum sect. Rhabdophyllum: four taxa are synonymized, three of which at the specific level and one at the infraspecific one, and fourteen lectotypifications are made.  相似文献   

13.
A new species, Aristolochia setulosa, is described from northeastern Brazil. Comments are given on geography and phenology, the species is illustrated, and a key to morphologically similar species is presented.  相似文献   

14.
Urban D  Parizotto DR 《ZooKeys》2011,(132):65-73
A new species of Michanthidium Urban (Hymenoptera, Megachilinae)is described and figured from Sergipe and Bahia States, northeastern Brazil. An identification key, illustrations, and a distribution map for the three species of the genus are presented. The male genitalia of Michanthidium almeidaisp. n. and Michanthidium albitarse are illustrated and compared for the first time.  相似文献   

15.
16.
This study explores whether ecological factors, such as pollinators and pollen flow, or variation in pollen and ovule development account for the observed differences (approximately twofold) in the reproductive output of pin and thrum individuals of Erythroxylum havanense. The importance of ecological factors was assessed by means of comparison of the identity of pollinators and the rates of flower visitation, and by performing controlled hand pollinations and measurements of fruit set. In addition, we described the pollen and ovule development of thrum and pin individuals. Our results indicate that pollinators of E. havanense do not distinguish between floral morphs. The differences in fruit set between pin and thrum plants held even after hand pollination and, therefore, the observed differences in reproductive output between floral morphs of E. havanense cannot be explained in terms of asymmetrical pollen flow. There were no differences in the pattern of gynoecium development between the pin and thrum morphs, however androecium development showed marked differences between the morphs, and there was a resemblance between the developmental pathways leading to male sterility of the thrum morph of E. havanense with that of species with cytoplasmic male sterility (CMS).  相似文献   

17.
A new species ofPaspalum,P. nummularium, is described and illustrated.  相似文献   

18.
Abildgaardia disticha from Estado da Bahia in Brazil is described as new. This species is unique in the tribe Abildgaardieae in having orthodistichous spikelets, and in several respects is intermediate between the subgenera Abildgaardia and Bulbostylis.  相似文献   

19.
Campomanesia espiritosantensis Landrum is described from the coastal forests of Espírito Santo, Brazil. Its relationship to other species in the genus is discussed.  相似文献   

20.
Rosana Romero 《Brittonia》2000,52(2):142-144
A new species of the genusMicrolicia,M. flava, from the highland “campo rupestre” vegetation of Serra da Canastra National Park, São Roque de Minas, Minas Gerais, Brazil, is described and illustrated.  相似文献   

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