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1.
Two new, closely related species of Struthanthus (Loranthaceae) are described, S. meridionalis from southern Bolivia and S. prancei from northern Brazil, each showing significant deviations from the generic norm in their inflorescence morphology. In both cases, a very high proportion of inflorescences bear bracteolate and/or ebracteolate monads as lateral units rather than the triads which characterize the rest of the genus. The place of inflorescence morphology in the development of generic concepts in small-flowered neotropical Loranthaceae is briefly reviewed, leaving the two new species in Struthanthus for the time being.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 469–474.  相似文献   

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Three new species of Galipea (Rutaceae, Galipeinae) are described and illustrated. Galipea carinata Pirani sp. nov. is known from the pluvial tropical forest in southern Espírito Santo State, eastern Brazil, and its main diagnostic features are the urceolate and conspicuously keeled calyx, the relatively short (14–16 mm) corolla tube, the long pedunculate, divaricate and loosely branched inflorescence, with few flowers crowded on tip of side branchlets, and the chartaceous leaflets, with lateral veins very prominent on both sides of the blade. Galipea revoluta Pirani sp. nov. is probably endemic to the coastal hygrophyllous Atlantic Forest in southern Bahia, eastern Brazil, and is very distinct by its mostly unifoliolate leaves, with a leathery, shiny lamina that is thickened and usually revolute at margin, by its calyx with large glands only at the base, and median nerve on each sepal. Galipea congestiflora Pirani sp. nov. is from forests on terra firme (non-inundated vegetation) of eastern Amazonia, most of them from the State of Pará, some others from eastern Maranhão and north of Tocantins. It is characterized mainly by 3-foliolate, chartaceous and dull leaves; a dense, corymbiform thyrsoid (partial inflorescences very short, crowded on top of the peduncle), which is smaller than the leaves; relatively large capsules (the largest in the genus) with an acute rim at the tip of each valve, and by the marmorate surface of the seeds. A brief discussion on the relationships of the new taxa to other species of Galipea is provided.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144, 365–373.  相似文献   

3.
Sophora tomentosa , the type species of the genus Sophora , is shown by phylogenetic analyses of rbc L and ITS sequence data to be sister to Sophora sect. Edwardsia . S. tomentosa and most of the species from sect. Edwardsia share hypogeal germination, exstipulate leaves, and terete filaments. These species have buoyant seeds, and are distributed by ocean currents throughout the pantropics ( S. tomentosa ) and around southern temperate oceanic islands (sect. Edwardsia ). S. tomentosa differs from the species of sect. Edwardsia by its frutescent growth habit, terminal elongate inflorescence and smooth-walled legume. S. macrocarpa is unusual in sect. Edwardsia as its leaves have stipules, the filaments are winged, and the legume is smooth-walled.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 439–446.  相似文献   

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In many plants, including orchids, differential fruit set along the inflorescence has been attributed to pollinator behaviour. For instance, the pollinator, moving up the inflorescence, becomes satiated with the resources and leaves before visiting the upper flowers. Consequently, the pollinators do not visit flowers as frequently higher up the inflorescence. Alternatively, flower size may vary along the inflorescence, making pollination ineffective as flowers decrease in size. I tested for the presence of differential pollination along the inflorescence in a pollinator-limited tropical epiphyte, Lepanthes rupestris Stimson, and determined the likely cause of the observed pattern. As this species has inflorescences with sequential flowering, pollinator behaviour, moving up the inflorescence as in synchronous multiflowering inflorescences, can be discounted as an explanation for differential fruit set. Fruit set is shown to be more frequent at the base of the inflorescence, but male reproductive success through pollinarium removal is basically independent of flower position. Moreover, cross-pollination by hand at variable flower positions along the inflorescence results in equal fruit set, suggesting that resources are not limiting and cannot explain the cause of differential fruit production along the inflorescence in natural populations. Furthermore, flower size is shown to diminish along the inflorescence, suggesting that the pollinator(s) may be ineffective at depositing the pollinarium in the smaller higher flowers. Consequently, pollinator behaviour and its interaction with flower size, and not resource limitation, is likely to be the main cause of differential fruit set along the inflorescence in L. rupestris .  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 405–410.  相似文献   

6.
Tragopogon cazorlanum (Asteraceae: Lactuceae) is proposed as a new Spanish species with distribution restricted to the Baetic mountains (south-eastern Spain). Its morphological, palynological, chromosomal, biogeographical and ecological features are discussed, as well as its main relationships and differences with reference to other Spanish species of the genus.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 505–511.  相似文献   

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Inflorescences of the Central American understorey palm Calyptrogyne ghiesbreghtiana offer bats fruit-like flower tissue as reward for visitation. Bats visited the inflorescences in two different modes: frugivores (Phyllostomidae: Stenodermatinae, Carolliinae) foraged on the inflorescence while perched, whereas bats that were primarily nectarivores (Phyllostomidae: Glossophaginae) also consumed flower tissue, but did so while hovering. Fruit set was significantly lower in inflorescences that had received only hovering visits, indicating that perching behaviour offers better possibilities for pollen transfer. The pollination system of C. ghiesbreghtiana is probably adapted to perching frugivorous bats with nectar-specialist Glossophagines as non-optimal participants. Seen in an evolutionary perspective the C. ghiesbreghtiana– glossophagine bat interactions may demonstrate recruitment of new pollinators from non-destructive visitors.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 80 , 281–288.  相似文献   

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The reproductive success of Arum italicum in south-western France showed a positive relationship with plant vigour at both the plant (number of inflorescences) and inflorescence (number of seeds) levels. However, the infructescence and berry numbers were not related to the number of inflorescences, and two-fold more seeds were produced by individuals flowering several times than by those flowering just once. Moreover, the reproductive success of this species appeared to be limited by the high abortion rate (50%), strong predation pressure on the inflorescences (34%), and low seed set rate of nonpredated inflorescences (36%), suggesting pollination limitation. Nevertheless, a positive relationship was found between the mean number of Psychoda trapped per inflorescence and the number of maturing infructescences, particularly for the most abundant species, Psychoda crassipenis . Therefore, pollinator availability appeared to be an important limiting factor for fructification in the studied population, by contrast with other studies in which the fruit set appeared to be related more strongly to the density of inflorescences. Such different results may have been caused by the relatively low abundance of Psychoda in the present study.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 43–49.  相似文献   

11.
Khaosokia caricoides , D.A. Simpson, Chayam. & J. Parn., a newly discovered genus and species of Cyperaceae is described and illustrated. The genus is characterized by a narrowly paniculate dioecious inflorescence with 2–4 nodes, each of the nodes having a leaf-like inflorescence bract that exceeds the inflorescence. Spikelets in both sexes are linear-cylindric and each flower has seven perianth bristles. The nutlet was immature in the specimens examined. The photosynthetic pathway is C3. Khaosokia is endemic to limestone cliffs in peninsular Thailand; its conservation status is assessed as Vulnerable (VU B1a + 2a). It has affinities to tribes Cariceae, Dulichieae and some members of Scirpeae, but the exact nature of these relationships has yet to be determined. A revised key to the genera of Cyperaceae in Thailand is presented.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 357–364.  相似文献   

12.
The palaeotropical tribe Hymenodictyeae Razafim. & B. Bremer, belonging to the otherwise predominantly Neotropical subfamily Cinchonoideae  s.s. (coffee family or Rubiaceae), is revised here. The tribe as presently circumscribed contains two genera, Hymenodictyon Wall. and Paracorynanthe Capuron ex J.-F. Leroy, and is distinct from the other Cinchonoideae tribes with capsular fruits in having stipules bearing large, deciduous colleters on the margins, valvate corolla aestivation, and lenticellate capsular fruits that contain elongate, bilaterally flattened, and accrescent placentae. We recognize 22 Hymenodictyon species, including four new species ( H. antakaranensis sp. nov. , H. epiphyticum sp. nov. , H. madagascaricum sp. nov. , and H. tsingy sp. nov. ), and the two described species of Paracorynanthe . Hymenodictyon is distinguished from its sister genus, Paracorynanthe , by simple or compound spicate, racemose or thyrsoid inflorescences and corolla lobes without any appendages, rather than compound umbelliform inflorescences and corolla lobes prolonged by ciliate appendages. A full taxonomic treatment, keys, and distribution maps of all recognized Hymenodictyon and Paracorynanthe species are provided. Five lectotypes and one neotype are designated. Finally, six Hymenodictyon species are illustrated for the first time.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 331–386.  相似文献   

13.
Twenty-seven chromosome counts are reported in 23 species of the genus Centaurea , mostly eastern endemic species of the Jacea group, which has become the core of the re-defined genus Centaurea . Twenty reports are new, one is a correction of a previous count, one is a confirmation of limited previous data and one represents a new basic number in the Centaureinae. The prevalence of the basic chromosome number x  = 9 among the Eastern sections of the Jacea group is confirmed, together with the close correlation between karyological data and classification of the genus. Two alternative hypotheses on the aberrant chromosome number (for the Centaureinae) found in C. behen are proposed. One of them, if verified, would confirm that a cycle of polyploidy and descending dysploidy is a key mechanism in the speciation of the group.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 345–352.  相似文献   

14.
A new species of Orchidaceae, Epidendrum caparaoense W.Forst. & V.C.Souza, is described and illustrated. This species is known only from the type locality, Caparaó National Park, in Minas Gerais State, where it grows on low tree trunks in gallery forests, at approximately 1300 m. The taxon is distinct from the other species of the genus by its laterally compressed stems, a long tubular spathaceous bract at the base of the inflorescence, a labellum with the free portion three-lobed and the clinandrium with an entire margin. It is considered similar to E. geniculatum and E. hololeucum .  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 155 , 157–159.  相似文献   

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A new genus Simplicaris (Copepoda, Harpacticoida, Parastenocarididae) is established to accommodate two species collected from deep groundwater in Italy, S. lethaea sp. nov. and S. veneris (Cottarelli & Maiolini, 1980) comb. nov. Parastenocaris hippuris Hertzog, 1938 and P. aedes Hertzog, 1938 are ranked as incertae sedis within the genus. Members display complete absence of leg 5 in both sexes and an unusual elongation of the first exopodal segments of legs 1–4, in which exp-1 is distinctly longer than exp-2 or -3, or as long as exp-2 and -3 combined. As the systematic status of the family Parastenocarididae and of the type genus Parastenocaris is still in flux, a list of phylogenetically informative characters is proposed, along with a discussion of their various states in representative members of the family. The genus Parastenocaris sensu stricto is redefined to comprise only the brevipes -group. The remaining members of the genus are considered Parastenocaris sensu lato pending a thorough revision of the family.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 417−436.  相似文献   

19.
Chromosome number and morphology in 14 taxa belonging to 19 populations of Tripleurospermum Sch. Bip. were studied using karyological and numerical taxonomical techniques. Data on chromosome measurements were analysed using cluster analysis. Chromosome numbers of these taxa are 2 n  = 2 x  = 18, 4 x  = 36 and 5 x  = 42–48. Seven records are new, two are not consistent with previous counts, and the remainder confirm the very limited previous data (one to three records). A new ploidy level (pentaploidy) is reported for the first time for the genus. Some correlations between ploidy levels and morphological characters are noted and several systematic and evolutionary aspects of the genus are discussed in the light of karyological data.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 146 , 427–438.  相似文献   

20.
Nigella turcica a new species endemic to north-eastern Turkey is described and illustrated. Morphological differences between the species and the closely related species, N. sativa , are discussed and the IUCN threatened category is proposed. A distribution map of the new species and its related taxon is given.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 251–255.  相似文献   

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