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1.
Manfred Bssler 《Feddes Repertorium》1981,92(3):179-254
Lathyrus sect. Lathyrostylis includes 20 Eurasian species that are more or less xerophytic. They are mainly distributed in South Europe and Southwest Asia, especially in Turkey. The majority of the species inhabits dry meadows, scrubs, Pinus forests, macchies, rocky slopes and screes. The following diagnostic characters are valuable: All species are perennial. The pinnate leaves consist of (1–)2–3(–8) pairs of parallelveined, amphistomatic leaflets and the rachis ending in a simple tip. The style is linear to broadly spathulate but not twisted. Within the section neither subsections nor series can be distinguished. The study is mainly based on herbarium specimens. Only few species had been cultivated. A key to species and subspecies and new maps, mainly based on revised herbarium specimens, are given. Species and infraspecific taxa are described, and their variability, relationships, phytogeography and ecology are discussed. At last some supplements and corrections to the revision of Lathyrus sect. Orobus (Bässler 1973) are added. 相似文献
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Saleem Esmael Shahbaz Jihad Ibrahim Saleem Shamiran Salih Abdulrahman 《Nordic Journal of Botany》2015,33(1):50-56
Rhus coriaria var. zebaria from Duhok/Aqrae, Kurdistan, Iraq is described as a variety new to science. Field expeditions started in spring 2011, continued during 2012 and 2013 with the aim of collecting sumac specimens from different physiographic regions of Kurdistan, Iraq. A total of ten plants for each variety were sampled. An equal number of tagged herbarium specimens were prepared. The holotype was designated and deposited together with other herbarium specimens in the herbarium of the Faculty of Agriculture and Forestry, Univ. of Duhok. Morphological characters of the leaf, inflorescence, flowers, infructescence, and fruit were studied. The pH value of the pericarp in addition to the hilum length was measured. Results were compared with Rhus coriaria L. var. coriaria. The most distinctive feature of the new variety is the dull whitish brown color of the drupe pericarp of var. zebaria as compared to the reddish brown color of the drupe pericarp of var. coriaria. The whitish color of the drupes of var. zebaria, in combination with their larger size, represents diagnostic characters for distinguishing this variety. In contrast, most leaf characters are of little or no taxonomic value in this species. Only shape, apex and marginal teeths of the leaflets show minor differences for separating the two varieties. Female and male inflorescences and flowers characters show no significant differences. Both hilum length and pH value characters may be useful for taxonomic application if mean values are taken in consideration. 相似文献
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David J. Hearn 《Brittonia》2007,59(4):308-327
Four new species and one new combination ofAdenia are presented, along with a vegetative key and diagnostic characters of the Madagascan species. Additional notes are provided
about unusual specimens and field observations.Adenia kigogoensis from Tanzania is shown to be distinct fromA. stenodactyla (its putative closest relative) andA. digitata based on anther connation and other floral traits. The remaining new taxa are from Madagascar.Adenia litoralis has been observed from one coastal locality in northern Madagascar. It is distinctive in fruit size and leaf form.Adenia metamorpha is the only Madagascan taxon with a narrow cylindrical trunk and large napiform tuber; it is also known from only one locality
in Madagascar in the Ankarana Reserve.Adenia mcdadiana is a robust liana with highly reduced glands and leaves that appear to be neotenic compared to its closest putative relative,A. sphaerocarpa. Finally, the position ofA. stylosa has been clarified. This species was once treated asA. firingalavensis var.stylosa, and prior to that asA. epigea var.stylosa, but molecular and morphological data suggest it is separate from these species. 相似文献
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The variation and recognition of taxa within the Hemizygia bracteosa complex was examined using multivariate techniques. Morphological characters were sampled on 197 herbarium specimens. Phenetically
H. bracteosa and H. welwitschii overlap in many floral characters. However differences in leaf characters and habit maintain their morphological distinctness
from each other and they are therefore upheld as species. Hemizygia ornata, synonymized under H. welwitschii in recent treatments of the genus Hemizygia, differentiates from H. welwitschii on the basis of differences in leaf and floral characters and its reinstatement at specific level is here proposed. The concept
of H. linearis is revised on account of the type specimen separating from all other elements of the taxon used in the analyses. The latter
form a coherent group with H. petrensis and H. canescens thus negating any attempt to give any of them specific recognition. It is proposed that they should be synonymized under
the earliest name H. canescens. The specific boundary of H. petiolata is revised but its specific status maintained. 相似文献
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To examine diagnostic characters and test phylogenetic relationships between Salsola arbusculiformis and the closely similar S. laricifolia, characters were examined from previous reports and herbarium specimens, and sequences of nrDNA ITS and cpDNA psbB–psbH were compared for these species as well as other representative taxa of Salsoleae. Our results 1) confirm most of the morphological differences highlighted in previous studies, such as those of leaf size, bracts, bracteoles, style, fruiting perianth, and anther appendages; 2) show that S. arbusculiformis is a typical Irano–Turanian species, mainly distributed from Iran and Turkmenistan to westernmost China (Tacheng, Ili, and Bole regions, Xinjiang), while S. laricifolia is a central Asian floristic element mainly distributed from east Kazakhstan and Kyrgyzstan to northern China (north Xinjiang, inner Mongolia, Ningxia and Gansu provinces), and Mongolia; and 3) strongly support their sister relationship, with samples from five different populations clustering together for each of the two species. 相似文献
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Scott L. Wing 《American journal of botany》1992,79(11):1320-1324
The foliar vein nets of many seed plants and ferns display systematically informative characters. These venation characters traditionally have been observed by chemically clearing and staining leaves, a process that is slow, involves toxic chemicals, and yields delicate, glass-mounted specimens that require long-term maintenance to prevent or correct bubbling or crystallization of the mounting medium. A technique that uses X-rays and photographic film to produce images of leaf venation consistently shows veins that are 50–100 μm thick. Although the X-ray images are slightly less detailed than the best cleared and stained leaves, the images can be made much more quickly, are more easily stored and reproduced, and do not require permanent alteration of the original herbarium specimen. The technique should facilitate the use of vein characters in systematics, and the identification and systematic analysis of fossil leaves. 相似文献
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Abstract The genus Coleura contains two species: C. seychellensis restricted to the Seychelles Archipelago and C. afra broadly distributed on the African continent and the Arabian Peninsula. We recently captured and collected specimens of Coleura from Madagascar, an island from which it was previously unknown. Using museum specimens and the new material from Madagascar, we review morphological variation in members of this genus and present characters for species identification. On the basis of these comparisons, specimens from Madagascar are referable to C. afra. We present information on the natural history of the recently discovered Malagasy population. 相似文献
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Reconstructing the spread of invasive plants: taking into account biases associated with herbarium specimens 总被引:8,自引:0,他引:8
Fanny Delisle Claude Lavoie Martin Jean Daniel Lachance 《Journal of Biogeography》2003,30(7):1033-1042
Aim To reconstruct the spread of invasive wetland species using herbarium specimens and to develop a method that accounts for the biases associated with this type of historical record. Location Southern Québec. Methods The temporal and spatial distribution of herbarium specimens of vascular plants was examined. Six invasive species that are mainly found in wetlands were compared with five native, non‐expanding hydrophytes. The cumulative number of locations was plotted against time to construct invasion curves. For native species, this ‘invasion curve’ indicates the spatiotemporal distribution of the sampling for herbarium specimens of wetland plants. It also represents the history of the state of knowledge of the distribution of native species. Deviation from the native species invasion curve can be used to describe the spread of invasive species. For every year on record, the cumulative number of locations of each exotic species was divided by the cumulative number of locations of all native species, and the proportions obtained were plotted against time. Periods of invasiveness were then delineated. Results During the twentieth century, two periods of intensive herbarium specimen collection in Québec can be clearly distinguished, i.e. from 1930 to 1940 and from 1950 to 1985. Several periods of invasiveness were delineated for Butomus umbellatus L. (1922–35), Hydrocharis morsus‐ranae L. (1957–96), Lycopus europaeus L. (1963–2000), Lythrum salicaria L. (1890–1905, 1923–46), Phragmites australis (Cav.) Trin. ex Steudel (1963–84) and Rorippa amphibia (L.) Bess. (1929–34, 1943–52, 1971–79). Main conclusions Accounting for sampling biases associated with herbarium specimens is important in order to objectively delineate periods of invasiveness for exotic species. The spread of wetland vascular plant species can be reconstructed using herbarium specimens, even when the phenomenon is rapid, but the reconstruction is certainly more accurate when the invasion occurred during an active sampling period. The highly variable sampling effort for herbarium specimens in Québec and in other regions strongly cautions against using herbarium data without correction procedures. 相似文献
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Amaranthus pumilus is known from coastal Massachusetts to South Carolina and from ballast in Philadelphia, Pennsylvania. It is currently listed
by the United States Fish and Wildlife Service as a threatened species.Amaranthus pumilus was originally described by Rafinesque in 1808 from southern New Jersey, but he did not cite specimens. Here, the nameA. pumilus is lectotypified using the only known original element, a Rafinesque specimen at the herbarium of The Academy of Natural
Sciences, Philadelphia (PH). 相似文献
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通过对野生植物及馆藏标本的观察比较,确认伞花野丁香(Leptodermis umbellata Batalin)与文水野丁香(L.diffusa Batalin)为同种植物,故予以归并。 相似文献
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Maria Rosaria Barone Lumaga Mario Coiro Elisabeth Truernit Boglrka Erdei Paolo De Luca 《Botanical journal of the Linnean Society. Linnean Society of London》2015,179(2):236-254
The genus Dioon occupies an important phylogenetic position as sister to the other Zamiaceae. However, its epidermal morphology is still poorly known. We employed scanning and transmission electron microscopy, confocal microscopy and light microscopy to examine the epidermal and cuticular morphology of 12 of the 14 currently recognized species of Dioon, examining cultivated plants and herbarium specimens. Epidermal characters separate Dioon quite clearly from the other genera of the cycads. Within the genus, the major subgroups can be distinguished by their epidermal morphology. Some characters, such as the degree of stomatal protection, reflect ecological specializations in species within the subgroups. Several epidermal characters of the crown group Dioon seem to be absent in the Cenozoic fossils usually associated with the genus, which have been used as calibrations in many recent molecular dating analyses. The presence of similar characters in a Mesozoic fossil adapted to volcanic stress offers a new key in the interpretation of Dioon evolution. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 236–254. 相似文献
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A classical morphological study ofHyacinthoides sect.Somera in the northwestern Iberian Peninsula revealed the new speciesH. paivae. It differs from the closely related speciesH. italica, H. hispanica, andH. mauritanica by vegetative and generative characters, such as leaf length, raceme shape, tepal length and width. It typically occurs in woodlands in the A Coruña province of NW Spain. 相似文献
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The first definitive Middle Jurassic atoposaurid (Crocodylomorpha,Neosuchia), and a discussion on the genus Theriosuchus
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Mark T. Young Jonathan P. Tennant Stephen L. Brusatte Thomas J. Challands Nicholas C. Fraser Neil D. L. Clark Dugald A. Ross 《Zoological Journal of the Linnean Society》2016,176(2):443-462
Atoposaurids were a clade of semiaquatic crocodyliforms known from the Late Jurassic to the latest Cretaceous. Tentative remains from Europe, Morocco, and Madagascar may extend their range into the Middle Jurassic. Here we report the first unambiguous Middle Jurassic (late Bajocian–Bathonian) atoposaurid: an anterior dentary from the Isle of Skye, Scotland, UK. A comprehensive review of atoposaurid specimens demonstrates that this dentary can be referred to Theriosuchus based on several derived characters, and differs from the five previously recognized species within this genus. Despite several diagnostic features, we conservatively refer it to Theriosuchus sp., pending the discovery of more complete material. As the oldest known definitively diagnostic atoposaurid, this discovery indicates that the oldest members of this group were small‐bodied, had heterodont dentition, and were most likely widespread components of European faunas. Our review of mandibular and dental features in atoposaurids not only allows us to present a revised diagnosis of Theriosuchus, but also reveals a great amount of variability within this genus, and indicates that there are currently five valid species that can be differentiated by unique combinations of dental characteristics. This variability can be included in future broad‐scale cladistics analyses of atoposaurids and closely related crocodyliforms, which promise to help untangle the complicated taxonomy and evolutionary history of Atoposauridae. © 2015 The Authors. Zoological Journal of the Linnean Society published by John Wiley & Sons Ltd on behalf of The Linnean Society of London 相似文献
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Hygrohypnum subeugyrium was first reported for Britain in 1976, but it has been ignored in subsequent British floras and identification guides. Morphologically it is a distinct species. New localities were discovered during a meeting of the British Bryological Society in Scotland in 2017. A subsequent revision of herbarium material has shown that H. subeugyrium is widely distributed in Scotland and occurs southwards to a few localities in England and Wales. Its extra-European distribution is extended to include the Himalayan region (Sikkim and Yunnan). It is described and illustrated, and its diagnostic characters are discussed. 相似文献
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Primarily, 50 characters taken from herbarium specimens, cultivated plants, and whole populations ofPrimula veris L. were critically evaluated. Only 24 characters were found to be suitable for taxonomic use. The geographical and multivariate analysis of about 1000 herbarium specimens from the whole area lead to a reduction of the number of subspecies. Only a less restricted subsp.veris (incl. subsp.canescens, subsp.inflata and probably including subsp.macrocalyx) and subsp.columnae (incl. subsp.suaveolens) can be distinguished considering the variability of characters within an individuum, under different culture conditions, and during the growth period. The status of the taxon macrocalyx cannot be cleared presently. 相似文献
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Eric A. Fischer 《Ethology : formerly Zeitschrift fur Tierpsychologie》1984,66(2):143-151
The simultaneously hermaphroditic fish, Hypoplectrus nigricans, engages in a form of reciprocal spawning called “egg trading”, where one partner gives up eggs for fertilization in exchange for the opportunity to fertilize those of the partner. Since egg trading appears to be important in the evolutionary maintenance of hermaphroditism in H. nigricans, an attempt was made to determine if another species, Serranus tortugarum, behaved in a similar fashion. S. tortugarum do trade eggs, and the phenomenon seems to be widespread in simultaneously hermaphroditic serranids. However, the cues for spawning are much subtler than in H. nigricans and other simultaneously hermaphroditic serranids. This trait appears to be an evolutionary response to the occurrence of heavy sperm competition in the form of streaking. 相似文献