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Floral morphology, distribution, and flower visitors for 60 taxa of Nasa are investigated and compared to molecular trees inferred both from a combined marker analysis (ITS1 and trnL(UAA)) and from a single marker (ITS1). Flowers ...
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Floral morphology, distribution, and flower visitors for 60 taxa of Nasa are investigated and compared to molecular trees inferred both from a combined marker analysis (ITS1 and trnL(UAA)) and from a single marker (ITS1). Flowers conform to two different floral types: Firstly, "tilt-revolver flowers", with spreading to reflexed, white to yellow petals and small, brightly coloured floral scales contrasting with the petals and firmly enclosing the nectar (Saccatae and Carunculatae); secondly, "funnel-revolver flowers", with half-erect to erect, orange to red petals and floral scales not contrasting with the petals, or enclosed in the corolla, and nectar freely accessible by funnel-shaped floral scales (Alatae, Grandiflorae, and N. venezuelensis species group). Phylogenetic analysis shows that "tilt-revolver flowers" represent the plesiomorphic condition by outgroup comparison. The two groups with tilt-revolver flowers in Nasa are not monophyletic (Saccatae are paraphyletic, Carunculatae are polyphyletic). Most Saccatae fall into two monophyletic assemblages, the N. poissoniana species group and the N. triphylla species group. The remainder of Saccatae group either with Grandiflorae (N. insignis species group) or with Alatae (N. taxa species group). The clades retrieved in the molecular analysis contradict the traditional classification, but are congruent with vegetative morphology, details of the flower morphology, and biogeography. "Funnel-revolver flowers" represent the derived condition, but molecular data suggest a convergent development (at least twice independently), since the corresponding species do not constitute a monophyletic group. "Tilt-revolver flowers" are visited and pollinated by bees (especially Colletidae), whereas "funnel-revolver flowers" are mostly visited by hummingbirds. The transition from melittophily to ornithophily may have been the license for the colonization of, and the diversification in, both cloud forest and high Andean habitats.
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South Andean Loasas (Blumenbachia, Caiophora, Loasa, Scyphanthus) are a monophyletic group of taxa within Loasaceae subfam. Loasoideae, comprising some 100 species, 49 of which are investigated here. They retain a many-layered tes...
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South Andean Loasas (Blumenbachia, Caiophora, Loasa, Scyphanthus) are a monophyletic group of taxa within Loasaceae subfam. Loasoideae, comprising some 100 species, 49 of which are investigated here. They retain a many-layered testa in the mature seeds and usually have passive transfer testas with complex, spongiose wall outgrowths. Additional modifications concern the undulations of the testa epidermis, presence or absence of the outer periclinal wall, secondary sculpturing, the presence or absence of spines, warts and finally spongiose structures on the anticlinal walls of the testa epidermis and the inner periclinal wall. Seeds of the widespread "deeply pitted" type are plesiomorphic, while various subclades of South Andean Loasas have derivations underscoring their relationships and confirming the relationships found with molecular markers and other morphological characters. The genus Blumenbachia has either seeds with a many-layered testa forming longitudinal lamellae (sect. Angulatae), or balloon seeds with a loose outer testa layer and spongiose wall outgrowths on the inner periclinal walls (sect. Blumenbachia and sect. Gripidea) and is clearly monophyletic. Loasa s.str. (ser. Loasa, ser. Macrospermae, ser. Floribundae, ser. Deserticolae) is characterized by the presence of a subterminal hilum or hilar scar and one subgroup (ser. Loasa, ser. Macrospermae) by very large and heavy seeds with a collapsed testa. L. ser. Pinnatae, ser. Acaules, ser. Volubiles, Scyphanthus and Caiophora share more or less one seed types with minor modifications. Within Caiophora various derivations are observed, of which the gradual loss of the secondary sculpture of the inner periclinal wall is the most striking one. Anemochoria is the most widespread dispersal mechanism in South Andean Loasas and is achieved in at least five structurally different ways. (c) 2005 Elsevier GmbH. All rights reserved.
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An overview is provided over the perennial taxa in the Urtica dioica complex in Cyprus, Iran, Iraq, Lebanon, Syria and Turkey. The literature reports a variety of names for the taxa of this group in this region and the recognition...
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An overview is provided over the perennial taxa in the Urtica dioica complex in Cyprus, Iran, Iraq, Lebanon, Syria and Turkey. The literature reports a variety of names for the taxa of this group in this region and the recognition and taxonomic status of taxa differ between the respective floristic treatments. On the basis of both living and herbarium material the tentative recognition of the following taxa for these countries is here proposed: U. dioica subsp. cypria (endemic to Cyprus), U. dioica subsp. dioica (syn. Urtica haussknechtii; Iran, Iraq, Lebanon, Syria, Cyprus and Turkey, Europe, E USA, W, N & Central Asia), U. dioica subsp. pubescens (Turkey, also SE Europe east of Italy and Hungary, Ukraine, Russia), U. dioica subsp. kurdistanica (syn. U. xiphodon, U. dioica var. xiphodon, U. dioica var. subincisa; Iran, Iraq, Syria, Turkey) and U. fragilis (Turkey, Lebanon). The subspecies of U. dioica show relatively weak morphological and ecological differentiation, comparable to that observed in Asian and North American subspecies of this group, but the recognition of subsp. cypria is recommended on the basis of weak, but highly consistent morphological characters, such as the distribution of stinging hairs and its exclusively monoecious character. U. fragilis can be considered as very distinct and likely only remotely related..
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As part of a chemotaxonomic screening for iridoids in Loasaceae samples from 74 species, mainly from subfamily Loasoideae, were assayed using HPLC and TLC. The presence of the iridoid dimer tricoloroside methyl ester and other oli...
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As part of a chemotaxonomic screening for iridoids in Loasaceae samples from 74 species, mainly from subfamily Loasoideae, were assayed using HPLC and TLC. The presence of the iridoid dimer tricoloroside methyl ester and other oligomeric iridoids consisting of loganin and secoxyloganin moleties turned out to be characteristic for members of ser. Macrospermae and ser. Floribundae of the genus Loasa. In species of the genus Caiophora 10- hydroxyoleoside dimethyl ester and a further not yet identified iridoid serve as chemotaxonomic markers. Other monomeric iridoids (loganin, loganic acid, secoxyloganin, secoxyloganin methyl ester, sweroside, 8-epi-kingiside) are widespread throughout the whole family without having systematic value at subfamily or generic level.
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The functional floral morphology of the three genera of Vivianiaceae (= Ledocarpaceae, Geraniales), Rhynchotheca, Viviania and Balbisia, is compared. Likely pollination mechanisms are inferred from morphology and field observation...
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The functional floral morphology of the three genera of Vivianiaceae (= Ledocarpaceae, Geraniales), Rhynchotheca, Viviania and Balbisia, is compared. Likely pollination mechanisms are inferred from morphology and field observations. The flowers of Viviania are nectariferous and apparently zoophilous with nectar as the (primary) pollinator reward. Balbisia has pollen flowers without nectaries, its showy corolla indicates that it is also zoophilous with pollen as sole pollinator reward; bees were observed as flower visitors. One taxon (B. gracilis) may be anemophilous. Rhynchotheca has flowers without petals, with large, pendulous anthers and lacks nectaries. It shows synchronous mass flowering in its natural populations and is evidently anemophilous. A comparison with other Geraniales shows that nectar flowers with small anthers are likely the ancestral condition in Vivianiaceae. This suggests that the pollen flowers with larger anthers of Balbisia and Rhynchotheca may represent an apomorphic condition. The documentation of pollen flowers and anemophily in Vivianiaceae expands the range of known floral and pollination syndromes in Geraniales.
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The pharmaceutically interesting Delta6-FA 18:3Delta6c, 9c, 12c (gamma-linolenic acid) and 18:4Delta6c, 9c, 12c, 15c (steariclonic acid) appear to have evolved independently several times during plant phylogenetic evolution. They ...
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The pharmaceutically interesting Delta6-FA 18:3Delta6c, 9c, 12c (gamma-linolenic acid) and 18:4Delta6c, 9c, 12c, 15c (steariclonic acid) appear to have evolved independently several times during plant phylogenetic evolution. They typically occur in "clusters" of a few closely related species or genera in about a dozen different plant families throughout the plant kingdom. A hitherto-unknown "cluster of occurrence" has now been discovered in the New World plant family Loasaceae. gamma-Linolenic and steariclonic acids Occur exclusively in representatives of the newly described genus Nasa at significance levels of between 3 and 10%, each. Nasa had recently been separated from the older, more broadly circumscribed genus Loasa. The two Delta6-FA were not found in the closely related genus Loasa sensu stricto, nor in a number of other representatives of Loasaceae.
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In continuation of our phytochemical studies on Loasa acerifolia Dombey, Loasaceae, a further novel dimeric iridoid glucoside named loasafolioside, 1, was isolated from the leaves. The structure of 1 is similar to the recently iso...
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In continuation of our phytochemical studies on Loasa acerifolia Dombey, Loasaceae, a further novel dimeric iridoid glucoside named loasafolioside, 1, was isolated from the leaves. The structure of 1 is similar to the recently isolated iridoid dimer, asaolaside, but owns an hemiacetalic group at position 3 of unit b. Compound 1 exists as an isomeric mixture like the iridoid dimer, laciniatoside I, which has an identical unit b. The structure of 1 was established by 1D and 2D NMR (H H COSY, HMQC, HMBC) and FABMS experiments.
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