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1.
The Old World species of the genus Pouzolzia have been revised and 24 species and 13 infraspecific taxa recognised. Worldwide, the genus now totals 36 species and 17 infraspecific taxa. Pouzolzia sect. Memorialis Bennett & Brown (including the genera Gonostegia Turcz. and Hyrtanandra Miq.) is maintained here as a section of Pouzolzia. The characters used to separate Pouzolzia from Boehmeria are found to work worldwide. In the Old World, the genus ranges, west to east, from Senegal to Japan and the Solomon Islands, and, north to south, from China, the Himalayas and Yemen to South Africa, Madagascar, Australia and the Lord Howe, Norfolk and Kermadec Is. Some species are common and occur almost throughout tropical Indomalesia or are widespread in Africa; others are rare and with a narrow range, for example restricted to one or a few oceanic islands. Each of the taxa occurring in the Old World is described and illustrated, habitats and geographical ranges are indicated, conservation status is discussed on the basis of our impression of old and new collecting activity, and distributions are mapped. The following new taxa are described: P. tsaratananensis Friis & Wilmot Dear from Madagascar, P. herpetophyton Friis & Wilmot‐Dear from the Comoro Is., and P. zeylanica subsp. calcicola Friis & Wilmot‐Dear and P. thailandica Friis & Wilmot‐Dear, both from southern Thailand. A new name, P. variifolia Friis & Wilmot‐Dear, is proposed for P. heterophylla (Blume) Wedd., nom. illeg. The following new combinations are published here: P. australis (Endl.) Friis & Wilmot‐Dear, P. sanguinea (Blume) Merr. var. formosana (Li) Friis & Wilmot‐Dear, P. sanguinea (Blume) Merrill var. cinerascens (Blume) Friis & Wilmot‐Dear, P. mixta Solms var. shirensis (Rendle) Friis & Wilmot‐Dear, P. hirta (Blume) Hasskarl var. parvifolia (Wight) Friis & Wilmot‐Dear, P. pentandra (Roxb.) Benn. & R. Br. subsp. wightii (Benn. & R. Br.) Friis & Wilmot‐Dear. and subsp. wightii (Benn. & R. Br.) Friis & Wilmot‐Dear var. gracilis (Miq.) Friis & Wilmot‐Dear. The following taxa are reduced to synonymy for the first time: Pouzolzia argenteonitida W.‐T. Wang, P. bracteosa Friis, P. calophylla W.‐T. Wang & C.‐J. Chen, P. guineensis Benth. var. seyrigii Leandri, P. guineensis Benth. var. madagascariensis Wedd., P. baronii Leandri, and P. auriculata Wight. 相似文献
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Eduardo G. Gonçalves 《Nordic Journal of Botany》2011,29(4):385-390
Two new species of Philodendron– Araceae (Philodendron bernardopazii E. G. Gonç. and Philodendron ricardoi E. G. Gonç.), so far known to be endemic to the Espirito Santo State, Brazil, are here described and illustrated for the first time. Philodendron bernardopazii has been traded as an ornamental plant for more than 30 years, as one of several species popularly called Philodendron“Santa Leopoldina”, because of the Brazilian county where it has been collected. This new species is so far known from two cultivated stocks, both supposedly collected at the same location (around the village of Santa Leopoldina) and if it still exists in nature, it is probably threatened. Philodendron ricardoi has only been observed on rocks around the village of Estrela do Norte where huge populations can be seen growing in rocky outcrops in open areas. 相似文献
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We describe and illustrate the new species Actinocephalus verae (Eriocaulaceae: Paepalanthoideae). This species is endemic to the rocky outcrops of the Espinhaço range in Minas Gerais, Brazil. We make comparisons with Actinocephalus ithyphyllus and Actinocephalus ochrocephalus, the morphologically most similar species. The new species’ morphological variation, habitat, geographic distribution, and conservation status are discussed. 相似文献
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Plant establishment and growth on rocky outcrops in the Itatiaia massif (2400 m a.s.l.), southeastern Brazil, are limited by lack of soil and by freezing temperatures in winter nights. Mat‐forming species of different sizes and shapes on bare rock provide substrate for other plants to establish. The habitat preference of two geophytes, Stevia camporum (Asteraceae) and Alstroemeria foliosa (Alstroemeriaceae), was compared with regard to their association with the type of mat species and distinct rock topographies. The habitat preference of the mat species in regard to topography was also assessed. We found 1706 ramets of S. camporum and 1317 of A. foliosa in 253 vegetation islands ranging in size from 0.005 to 18.097 m2. Mat species in these islands were Fernseea itatiaiae, Vriesea itatiaiae (both Bromeliaceae), Pleurostima gounelleana (Velloziaceae) and/or Campylopus pilifer (Dicranaceae) and other mosses. Mat species were segregated by topography. Geophytes were similarly distributed across types of topography but showed negative interspecific association. S. camporum occurred mostly on the moss‐dominated islands, whereas A. foliosa was more common in P. gounelleana islands. We found geophyte co‐occurrence in larger vegetation islands containing both P. gounelleana and mosses as mat species. Thus, the effect of topography on geophyte segregation was indirect, since topography affects mat species distribution, and the geophyte preference for distinct mat species as substrate resulted in their segregation. 相似文献
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Questions: Do small rocky outcrops favor forest plant colonization and establishment in grasslands? If so, what are the potential mechanisms involved in this process? Location: Araucaria forest and Campos grassland mosaic in southern Brazilian highlands (29°29′S, 50°12′W). Methods: We collected data on the density of forest woody species in plots located on rocky outcrops and in open fields subject to different management regimes. We evaluated the influence of outcrops on the density of forest plants ≤60‐cm tall, and the effects of other environmental variables and of site on plant density; we also used information on diaspore traits of the species to discuss the way in which plants disperse to the outcrops. Results: Rocky outcrops harbored a significantly higher density of forest plants than open fields, irrespective of site effect, and rock height was the best predictor for plant density on outcrops. Diaspores of all recorded species possess characteristics associated with dispersal by birds or mammals or by both. Conclusions: Small rocky outcrops markedly influence forest expansion by acting as perches for vertebrate dispersers and as nurse objects and safe sites for plants. Forest expansion starting in small outcrops possibly occurs as follows: perching of dispersers and increase of seed rain on rocks, promotion of better conditions of establishment for forest plants by nurse rocks, protection of plants sensitive to grazing and fire, and nucleation of forest vegetation. 相似文献
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A fundamental part of developing effective biodiversity conservation is to understand what factors affect the distribution and abundance of particular species. However, there is a paucity of data on ecological requirements and habitat relationships for many species, especially for groups such as reptiles. Furthermore, it is not clear whether habitat relationships for particular species in a given environment are transferable to other environments within their geographical range. This has implications for the type of ‘landscape model’ used to guide management decisions in different environments worldwide. To test the hypothesis that species‐specific habitat relationships are transferable to other environments, we present microhabitat models for five common lizard species from a poorly studied habitat – insular granite outcrops, and then compared these relationships with studies from other environments in south‐eastern Australia. We recorded twelve species from five families, representing 699 individuals, from 44 outcrops in the south‐west slopes of New South Wales. Five lizard species were abundant and accounted for 95% of all observations: Egernia striolata, Ctenotus robustus, Cryptoblepharus carnabyi, Morethia boulengeri and Carlia tetradactyla (Scincidae). Linear regression modelling revealed suites of different variables related to the abundance patterns of individual species, some of which were broadly congruent with those measured for each species in other environments. However, additional variables, particular to rocky environments, were found to relate to reptile abundance in this environment. This finding means that species' habitat relationships in one habitat may not be readily transferable to other environments, even those relatively close by. Based on these data, management decisions targeting reptile conservation in agricultural landscapes, which contain rocky outcrops, will be best guided by landscape models that not only recognize gradients in habitat suitability, but are also flexible enough to incorporate intraspecies habitat variability. 相似文献
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Rocky outcrops usually have a peculiar vegetation which differs from that of the surrounding vegetation matrix. In Brazil, a savanna type (cerrado rupestre) is particularly characterized by rocky outcrops and is one of eleven vegetation types which occur throughout Cerrado biome. It has been scarcely studied in detail. Therefore, the aim of this study was to investigate the phytogeographical patterns of the woody species in ten areas of the rocky outcrop savanna in the Brazilian Central Plateau. The difference in spatial distribution of the species was assessed through indicator species and CCA ordination analyses. Ten indicator species showed significantly different distribution. The first axis of the ordination showed association with the edaphic gradient, based on maximum temperature, pH and physical properties of the soils (eigenvalue 0.63). The second axis showed an eigenvalue 0.46, associated with poor rainfall and land declivity. It appears that the woody flora of the rocky outcrop savanna areas of the Brazilian Central Plateau is relatively homogeneous, with low β diversity. Apparently, the size of the woody species populations is what distinguishes the ten investigated areas. Therefore, initiatives and actions for the Cerrado biome conservation must consider not only the size of the protected areas but also that of the populations to be protected, especially the woody species on rocky outcrops. 相似文献
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FERNANDO AUGUSTO OLIVEIRA SILVEIRA DANIEL NEGREIROS LUZIA MÁRCIA ARAÚJO GERALDO WILSON FERNANDES 《Plant Species Biology》2012,27(2):170-173
We tested the regeneration niche hypothesis by comparing the germination ecology of two sympatric Diplusodon species differing in their geographic range and microhabitat. Diplusodon orbicularis is an endemic shrub achieving high densities on sandy soils, whereas Diplusodon hirsutus has a wider geographic range and establishes on rocky outcrops. Seeds were set to germinate under constant temperatures of 15, 20, 25, 30 and 35°C under 12 h light/12 h dark conditions. Light induced germination in both species, but germination under darkness was also observed. Optimum conditions for germination were 25°C/light for both species. The lack of differences in soil temperatures between rocky outcrops and sandy soils provides evidence of no temperature‐dependent microhabitat selection. Unexpectedly, germinability of the more widespread species was lower than that of the endemic congener. Higher germinability of D. orbicularis may account for higher densities when compared with D. hirsutus. Our results provide limited support for the role of germination in contributing to ecological breadth and geographic range. 相似文献
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Sarah K. Pearson Gregory R. Johnston C. Michael Bull Aaron L. Fenner Michael G. Gardner 《Austral ecology》2020,45(4):435-443
By constraining gene flow, group living and natal philopatry can result in fine‐scale genetic structure. Although the genetic structure of some group‐living lizards has been characterised, studies are few compared with those for group‐living bird and mammal species. The Egerniinae group of lizards exhibits a high diversity of social structures, making it a useful group for comparative studies of genetic structure across a broader range of social taxa. A well‐studied member of Egerniinae is Egernia stokesii, a lizard that forms long‐term pair bonds and stable social groups and exhibits natal philopatry and limited dispersal. Evidence exists for consistent E. stokesii social structure across seven close but disconnected rocky outcrops within a 40 × 10 km area. We used summary statistics, analysis of molecular variance, Bayesian clustering, and discriminant analysis of principal components to assess if E. stokesii exhibit a consistent pattern of fine‐scale genetic structure across the same seven outcrops. Due to E. stokesii social structure and constrained dispersal, we predicted significant genetic structuring – based on microsatellite markers – among outcrops. We found significant fine‐scale genetic structuring and evidence for two genetic clusters. We discuss features of E. stokesii biology and ecology that may explain our findings. Some rocky outcrops, and some social groups, contained lizards from both genetic clusters. An examination of the composition of mixed cluster social groups did not detect any notable patterns. Therefore, further work is necessary to identify how the observed patterns may have arisen. Future investigations in E. stokesii and other group‐living lizard species are likely to contribute greatly to our understanding of the genetic consequences of group living. 相似文献
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Platycarpum vriesendorpiae sp. nov., a second new species of Tribe Henriquezieae (Rubiaceae) from nutrient‐poor soils in the Peruvian Amazon
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The new species Platycarpum vriesendorpiae N. Dávila (Rubiaceae, Henriquezieae) is described from Peru, where it is restricted to white‐sand forests and peatlands in the Tapiche and Blanco River watersheds in southeastern Loreto Region. The new species is generally similar to P. acreanum Rogers of western Brazil in its phyllotaxy, leaf pubescence, and fruit shape and size. However, P. vriesendorpiae differs in its triangular stipules that are 2‐ or 3‐angled at the base and in its smaller corolla. 相似文献
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The true identity of Obama (Platyhelminthes: Geoplanidae) flatworm spreading across Europe
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Fernando Carbayo Marta Álvarez‐Presas Hugh D. Jones Marta Riutort 《Zoological Journal of the Linnean Society》2016,177(1):5-28
Since 2008 there have been many records in Europe (British Isles, Spain, France, Italy) of a large terrestrial planarian morphologically very similar to the Brazilian species Obama marmorata. Sequences of mitochondrial (Cox1) and nuclear (18S, 28S, ITS‐1 and EF) genes from European specimens and some from Brazil indicate that they belong to a species different from that of other specimens also collected in Brazil. Moreover, the phylogenetic results show that they are not sister‐species. Histological sections of both Brazilian and European specimens reveal subtle morphological differences between the two species. Obama marmorata is confined to Brazil, and the second, herein described new species, O bama nungara sp. nov. , is found in Brazil and Europe. These cryptic species may be syntopic in areas in Brazil. The new species occurs in human‐modified environments both in Brazil and in Europe. We also conclude that the specimens from Spain and Argentina identified previously as Obama marmorata belong to the new species. 相似文献
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Summary
Allamanda calcicola Souza-Silva & Rapini, an overlooked new species endemic to the limestone outcrops along the S?o Francisco River Basin, in
south-western Bahia and northern Minas Gerais, Brazil, is described and illustrated. It was confused with A. martii and A. schottii, two species from eastern Brazil, which (along with A. polyantha) form a different complex of closely related species. However, A. calcicola is more closely related to A. puberula, another species from the semi-arid region of Brazil. 相似文献
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Guilherme H. S. Freitas Lílian M. Costa Pedro H. V. B. P. Silva Anderson V. Chaves Leonardo C. Ribeiro Marcos Rodrigues 《Journal of Field Ornithology》2019,90(2):128-142
Birds in the genus Cinclodes are habitat specialists, with most restricted to the highlands of South America. The recently described Cipo Cinclodes (C. espinhacensis) is isolated in the southern Espinhaço Range of Brazil and is considered Endangered in Brazil and Near Threatened by the IUCN, but as a subspecies of Long‐tailed Cinclodes (C. pabsti). We examined the population and spatial ecology of Cipo Cinclodes at two geographic scales to improve our understanding of their basic biology and conservation status. We monitored 30 birds at Serra do Breu and found relatively large home ranges (mean = 9.3 ha), a density of paired adults of 0.09/ha, a male‐skewed adult sex ratio (males/total adults = 0.57) due to territories occupied by unpaired males, and long‐term site fidelity. Cipo Cinclodes used all habitat types available in our study area, including rocky outcrops, grasslands, and riparian areas, but habitat selection analyses revealed the importance of riparian areas for foraging and rocky outcrops for nesting. At the species distribution scale, we compiled known and novel recorded occurrence points and used them to calculate the extent of occurrence (EOO) and the area of occupancy (AOO). We used a Maxent species distribution model to generate a binary map to estimate upper limits for EOO (EOO around the model predicted area) and AOO (comprised by the model predicted area within the EOO). We obtained 41 locations, resulting in an EOO of 890.7 km2 (up to 1748.7 km2) and an AOO of 100 km2 (up to 327.5 km2). The global population is estimated to be between 880 and 2882 birds, which is concerning because small populations are at risk of extinction due to demographic stochasticity, genetic drift, and the interaction of these factors. As such, our results support the designation of Cipo Cinclodes as Endangered on the Brazilian red list. 相似文献
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Summary
Ceiba rubriflora Carv.-Sobr. & L. P. Queiroz, a new species of Malvaceae subfamily Bombacoideae from the State of Bahia, Brazil, is described and illustrated. It is considered to be endemic to calcareous outcrops in the
valley of the Rio S?o Francisco, in the western region of the state. Notes on distribution, ecology and phenology are given.
Relationships with related species are discussed and an addition to the key to species of Ceiba Mill. published by Gibbs & Semir (2003) are provided. 相似文献
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The southern vizcacha (Lagidium viscacia) and the exotic European hare (Lepus europaeus) are two medium-sized herbivores that inhabit rocky outcrops in Patagonian steppe. These species overlap in diet and spatial use at medium distances from rocky outcrops in summer. We evaluated the spatial use through feces distribution in winter and determined seasonal foraging intensity in relation to the distances from rocky outcrops in order to elucidate how these herbivores use food and spatial resources in food scarcity periods. The vizcacha utilized the habitat close to rocky outcrops (<40 m) independent of season, while the hare exploited the space more widely, especially distances >40 m. However, in winter, at medium distances from rocky outcrops, there was partial spatial overlap because hares' activities were closer to rocky outcrops. Foraging intensity increased significantly in areas used by the vizcacha closer to rocky outcrops when food availability decreased, and the grasses Stipa speciosa, Poa sp., and Festuca pallescens were strongly foraged. In contrast, foraging intensity showed no changes in further distances to rocky outcrops and more use by the hare. The spatial and feeding behavior of the vizcacha, restricted to vicinity of rocky outcrops, showed high vulnerability to food availability changes. In resource scarcity situations, the spatial opportunistic behavior of the hare and the overlap in diet with the vizcacha constitutes a threat to this native herbivore. It is necessary to monitor populations of hare, since high densities could lead to food competition, impacting the small colonies of the southern vizcacha. 相似文献
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B. Büdel U. Becker S. Porembski W. Barthlott 《Plant biology (Stuttgart, Germany)》1997,110(6):458-465
This study focuses on the saxicolous lichens and cyanobacteria of the open, exposed rock surface of inselbergs. Twenty-three species of cyanobacteria and 17 cyanobacterial lichen species (“cyanolichens”) from several inselbergs and other rocky outcrops of three major climatic regions, savanna, transition zone and rain forest, are reported from the Ivory Coast. Inselbergs are isolated and frequently mountains consisting of Precambrian granites or gneisses that abruptly rise from the surrounding plains. Cyanobacteria were found to be the dominating organisms on all rock surfaces. The lichens found mainly belong to the family Peltulaceae and a few were present from the family Lichinaceae. Nine species of the cyanolichens and most of the cyanobacteria are new for the Ivory Coast. A gradient in total species number (cyanolichens and cyanobacteria) occurs from the savanna to the rain forest, with a decrease in species number towards the rain forest. Saxicolous cyanobacterial lichens reached a higher species number in the savanna type ecosystem (11) than on inselbergs in the rain forest (7). The cyanolichens and cyanobacteria found are characteristic for larger, light-exposed rock surfaces and species like P. congregate, P. lingulata, P. tortuosa and P. umbilicata preferentially occur on the granite or sandstone of inselbergs. 相似文献
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Ecological niche breadth and microhabitat guild structure in temperate Australian reptiles: Implications for natural resource management in endangered grassy woodland ecosystems
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Damian R. Michael Geoffrey M. Kay Mason Crane Daniel Florance Christopher MacGregor Sachiko Okada Lachlan McBurney David Blair David B. Lindenmayer 《Austral ecology》2015,40(6):651-660
Ecological theory predicts that species with narrow niche requirements (habitat specialists) are more vulnerable to anthropocentric disturbances than those with broad niche requirements (habitat generalists). Hence, understanding a species ecological niche and guild membership would serve as a valuable management tool for providing a priori assessments of a species extinction risk. It also would help to forecast a species capacity to respond to land use change, as what might be expected to occur under financial incentive schemes to improve threatened ecological vegetation communities. However, basic natural history information is lacking for many terrestrial species, particularly reptiles in temperate regions of the world. To overcome this limitation, we collated 3527 reptile observations from 52 species across an endangered woodland ecoregion in south‐eastern Australia and examined ecological niche breadth and microhabitat guild structure. We found 30% of species had low ecological niche values and were classified as habitat specialists associated with large eucalypt trees, woody debris, surface rock or rocky outcrops. Cluster analysis separated species into six broad guilds based on microhabitat similarity. Approximately 80% of species belonged to guilds associated with old growth vegetation attributes or non‐renewable litho‐resources such as surface rock or rocky outcrops. Our results suggest that agri‐environment schemes that focus purely on grazing management are unlikely to provide immediate benefits to broad suites of reptiles associated with old growth vegetation and litho‐resources. Our classification scheme will be useful for identifying reptile species that are potentially vulnerable to anthropocentric disturbances and may require alternative strategies for improving habitat suitability and reptile conservation outcomes in grassy woodland ecosystems. 相似文献
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Abstract. Question: Are tree saplings in wooded pastures spatially associated with specific nurse structures or plants that facilitate tree sapling survival? Location: Wooded pastures in the Jura Mountains, Switzerland. Methods: In two sites, 73 km apart, we sampled 294 plots of 4 m2, systematically distributed on 1 ha. We recorded number and height of all established Picea abies saplings (> 1 a of age and up to 40 cm in height), and visually estimated cover of rocks, shrubs, tree stumps, overhanging tree branches and unpalatable plant species. Results: Despite differences in site characteristics, we found overall positive effects of cover of unpalatable plants, rocky outcrops and tree stumps on the density of Picea saplings. Plots with tree stumps and higher cover of rocky outcrops and unpalatable plants were more likely to contain Picea saplings. Conclusions: Unpalatable plants, rocky outcrops and tree stumps seem to form safe sites for Picea saplings in this grazed system, improving their establishment and survival. Our findings support the idea that associational resistance drives the dynamics of wooded pastures, but experimental evidence for this hypothesis is still required. 相似文献