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Abstract.  Like many other organisms, Simuliidae often show a high degree of endemism on oceanic islands, and the Gulf of Guinea, including its islands, is a region of general biogeographical interest in view of the uniqueness of its flora and fauna. This paper presents a comprehensive review of the Simuliidae in the region, and is the first faunistic record of blackflies from Bioko. Simuliidae (larvae, pupae and neonate adults) were collected from Bioko and from around Mount Cameroon and compared with previous findings from Mount Cameroon, Príncipe and São Tomé. Twenty-seven species are known from the region. Twenty-five species have been recorded around Mount Cameroon, eight species on Bioko, three species on São Tomé and one species on Príncipe. Two taxonomic 'forms' (one on Bioko alone, and one on both Bioko and around Mount Cameroon) and one species (found only on São Tomé) are endemic to the region. A study of the variation in the morphology of Simulium cervicornutum revealed two morphotypes, one from Bioko and around Mount Cameroon and the other from the rest of Africa. The speciation and biogeography of the Simuliidae in the Gulf of Guinea are discussed.  相似文献   

3.
The forests of southwest Príncipe are recognized as important for biodiversity conservation. Here, we study the distribution and density of fifteen of the island's endemic bird species (including three Globally Threatened and one Near-Threatened) within the National Park. The endemic subspecies of the Near-Threatened Gulf of Guinea thrush occurred at a density of 0.08 birds ha−1, which is far lower than its sister subspecies on the neighbouring island of São Tomé. We also present evidence that the effects of access routes around the protected area exert an influence on bird species within the National Park. The grey parrot, which still suffers from illegal hunting, was more likely to be encountered further away from roads, with 25% of variation in its occurrence explained by distance to the nearest road. In addition, the occurrence of all four threatened species was more likely further from access routes. Careful consideration must therefore be given to the potential impacts within the National Park of developments outside the currently protected area.  相似文献   

4.
A treatment of the Rubiaceae of Cabinda (Angola) is presented based on various herbarium collections. There are 67 genera and 169 species of Rubiaceae represented in the flora of Cabinda. Eight entities are unnamed and could represent new taxa. Identification keys are provided for species and infraspecific taxa. A new combination is made in Rothmannia and two are made in Psychotria. A new name is provided in Psychotria . Eighteen taxa are endemic to Cabinda, two of which are also endemic to Angola. The conservation status of the endemic taxa is unknown due to the lack of collections over the last 40 years. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 455–495.  相似文献   

5.
A treatment of the Rubiaceae of Angola is presented based on herbarium collections kept at BM, BR, COI, K, LISC, LISU, LUA, LUAI, P, and PRE. The basionyms, relevant synonyms, and types from Angola are cited. For each taxon, one collection is cited for each province. An exsiccata list with over 3300 collections examined and identified during this work is provided. There are 108 genera, 422 species, and 40 infraspecific taxa of Rubiaceae in Angola. Fourteen genera and 126 species and infraspecific taxa are restricted to Cabinda. The rate of endemism of the family is c. 19%, with 86 taxa endemic to Angola (16 of which are restricted to Cabinda). Two genera are endemic. A new subspecies and a new variety are described. There are 21 unnamed entities requiring further research. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 537–638.  相似文献   

6.
A new species, Oxalis ferae Llorens, Gil & Cardona (Oxalidaceae) from the Balearic islands (Spain) is described and illustrated. It is considered to be endemic to Mallorca. The morphological differences between the more closely related taxa of Oxalis section Corniculatae are discussed. IUCN threatened category and observations on the ecology of the populations are noted.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 489–493.  相似文献   

7.
In all 101 species and varieties of marine algae are mentioned for S. Tomé and Príncipe. These records arise from examination of the material in the herbarium of the Botanical Institute of the University of Coimbra, together with material collected in 1956 by Dr C. A. Thorold. From the latter material there are 17 new records for the island of S. Tomé.
No new species have been described, but Acantkophora ramulosa Kütz. is emended, and Bryopsis densa Pilger and Struvea multipartita Pilger are reduced to the synonymy of Bryopsis pennata var. secunda and Struvea anastomosans respectively.
Information on the climate and tides of the islands is given, and a series of 'seasonal coincidences' likely to influence coastal marine conditions is described for the Gulf of Guinea.  相似文献   

8.
During the preparation of a World Rubiaceae Checklist , numerous unplaced taxa were encountered, including illegitimate and invalid names, and species for which generic placement is uncertain. In this contribution, 35 new combinations and 20 new names are proposed, and the names of three taxa are validated.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 115–124.  相似文献   

9.
A morphological (non-molecular) cladistic analysis of the Velloziaceae is presented. The terminal taxa are 47 species of Velloziaceae plus four taxa as outgroups: Acanthochlamys bracteata (Acanthochlamydaceae), Encholirium scrutor (Bromeliaceae), Thoracocarpus bissectus (Cyclanthaceae) and Pandanus racemosus (Pandanaceae). The species of Velloziaceae sampled represent a significant proportion of the morphological diversity of the family, including all recognized genera and sections. The analysis revealed two major groups within Velloziaceae, supported mainly by stomata, vascular bundles in the pedicel, aquiferous tissues, filaments, anthers, pollen, stigma, seeds, ploidy and chemical characters. Comparison between this and the previous phylogenetic hypotheses for Velloziaceae, together with the two conflicting current classifications, suggests that there is incompatibility concerning the support of current genera and sections. The only three groups supported in all phylogenies are Barbacenioideae sensu Menezes (= Barbacenia sensu Smith & Ayensu), Xerophyta sect. Barbacenioides and Xerophyta sect. Xerophyta sensu Smith & Ayensu.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 157–173.  相似文献   

10.
Twenty-six chromosome counts were made of several genera of the tribe Cardueae from various European and Asian provenances: Acantholepis (one species studied), Amphoricarpus (1), Chardinia (1), Echinops (14 species, 15 populations), Siebera (1), Staehelina (3) and Xeranthemum (4). Eleven of the reports are made for the first time, ten confirm previous counts, while the remainder report disparities with earlier records. The existence of different basic chromosome numbers and ploidy levels suggests dysploidy and polyploidy as the main mechanisms of chromosomal evolution in the taxa considered.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 337−344.  相似文献   

11.
This study provides a checklist of the Caesalpinioideae (Leguminosae) present in Equatorial Guinea, comprising 52 genera and 124 taxa. Seven species are known from Annobón, 33 from Bioko and 109 from Río Muni. The best represented genus is Senna with eight species. In addition, bibliographic references for Caesalpinioideae (Leguminosae) from Equatorial Guinea have been gathered and checked. Fourteen species are included based on literature records, because their distribution ranges suggest they may occur in Equatorial Guinea, 11 introduced species could be naturalized, and 45 taxa are recorded for the first time from the country. This represents an increase of over 35% in the floristic knowledge of Caesalpinioideae from Equatorial Guinea. A statistical summary is presented at the end of the checklist.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 541–562.  相似文献   

12.
Twenty-two chromosome counts of 19 taxa (21 populations) in the tribe Anthemideae and one member (one population) of the tribe Inuleae of the family Asteraceae are reported. The Anthemideae studied belong to the subtribes Artemisiinae (14 Artemisia taxa, and one species each of the genera Dendranthema , Filifolium and Neopallasia ) and Tanacetinae (one species each of the genera Lepidolopha and Tanacetopsis ). From the Inuleae, we studied one Inula species. Five counts are new reports (including two at generic level), six are not consistent with previous counts and the remainder are confirmations of very limited (one to four records) previous data. Most of populations of Anthemideae studied have the basic chromosome number x  = 9, with ploidy levels ranging from 2 x to 10 x . Dysploidy is also present, with two x  = 8 diploid taxa. The species of Inuleae studied is a diploid with x  = 10, also indicating dysploidy, other members of the same genus Inula having basic numbers of x  = 9 or 8.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 77–85.  相似文献   

13.
The Malagasy representatives of the large African genus Tricalysia (tribe Coffeeae s.l.) are revised. Three Malagasy species were hitherto recognized in the genus, namely T. cryptocalyx , T. madagascariensis , and T. ovalifolia . In this study, two species, T. boiviniana and T. leucocarpa , are transferred from the genus Hypobathrum and seven new species and two new subspecies are described, raising the species number for Tricalysia to a total of 12. This marked increase in species number is a recurring pattern for many Malagasy genera in systematically poorly known families such as Rubiaceae. All the species are described in detail and illustrated, and a list of exsiccatae and a distribution map are provided. Furthermore, the characters of the Malagasy taxa are compared with those of the continental African species, and their infrageneric status is discussed. With the exception of T. ovalifolia , a member of subgenus Empogona , all Malagasy species belong to subgenus Tricalysia . Because of their unisexual flowers, these species cannot be accommodated within one of the four existing sections in subgenus Tricalysia . A new section, Androgyne , is therefore recognized.  © 2007 National Botanic Garden of Belgium. Journal compilation © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 83–126.  相似文献   

14.
During the preparation of the Vascular Flora of the Marquesas Islands and Flore de la Polynésie française , four new species of Ixora L. (Rubiaceae) have come to light and are described and illustrated herein: Ixora jourdanii Mouly & J.Florence, Ixora tahuataensis Mouly & J.Florence, Ixora uahukaensis Lorence & W.L.Wagner, and Ixora uapouensis Lorence & W.L.Wagner. In addition to these new taxa, the following three species of Ixora previously described from the Marquesas are recognized: Ixora marquesensis F.Br., Ixora ooumuensis J.Florence, and Ixora spathoidea F.Br. As the Marquesan environment is under serious threat from human impact, feral animals and weeds, the conservation status was estimated for each Ixora species. It is concluded that all Marquesan taxa are in need of inclusion in the IUCN Red List, their status ranging from endangered to critically endangered.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 581–597.  相似文献   

15.
Hybridization phenomena can be considered in different ways. Hybridization studies can be used to elucidate some aspects of speciation and adaptation. However, hybridization may be a threat to endemic species. Here, we studied bidirectional introgression between two sympatric species of Cyprinidae: Chondrostoma toxostoma toxostoma and C. nasus nasus . Analysis of morphology, allozymes and mtDNA sequences revealed that the hybridization between these two cyprinids takes different forms in the same river. The mosaic hybrid zone (so called because of the absence of a simple cline) appeared to be partitioned due to the proportions of the two species along a spatial scale. The proportion of each hybrid group in this zone was unstable over a 5-year period. We propose various protection/conservation states for the C. t. toxostoma populations based on the level of introgressive hybridization and the genetic structure of both species in 'pure' populations.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 85 , 135–155.  相似文献   

16.
A re-evaluation of Minuartia graminifolia has been undertaken based on comparative morphological studies. M. graminifolia subsp. rosani (an endemic of the south-central Apennines and Sicily) and subsp. hungarica (an endemic of the Banat region of Romania) are accepted infraspecific taxa. M. graminifolia subsp. hungarica is lectotypified. M. graminifolia subsp. clandestina is confirmed for Italy; the taxon is neotypified. The type subspecies is considered an endemic to the east-central Alps. Keys to the species of Minuartia ser. Graminifoliae and to the subspecies of M. graminifolia are provided.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 419–432.  相似文献   

17.
The importance of the rainforests on the island of São Tomé for biodiversity is well known. However, the area only recently received full legal protection as a National Park and currently few resources are available to enforce that legislation. With rapid economic development forecast for the island, active conservation efforts are essential. Here we study the distribution and density of the island's endemic bird species, including nine that are Globally Threatened, within the National Park. Sites, covering the full range of primary forest types, were surveyed using distance sampling methods. No introduced species were observed. The highest number of species, including eight Globally Threatened species, were found in lowland rainforest, although many were infrequently encountered. Higher altitude sites were less diverse, but supported some of the common endemic species at extremely high densities. The least diverse assemblage, with generally lower species population densities, occurred at the most accessible mid-altitude forest site. Distance from settlements was a key explanatory variable for the presence of all Globally Threatened species, indicating that human habitation has negative effects on the suitability of nearby forest habitats. This suggests that, as infrastructure improvements proceed, populations of endangered species will come under growing pressure. Integrating the needs of biodiversity conservation and development represents a major challenge for many biodiverse countries and on São Tomé, as elsewhere, may best be achieved by preserving the still intact functioning forest ecosystem.  相似文献   

18.
Preliminary checklist of the orchids of Chile   总被引:1,自引:0,他引:1  
This article provides a preliminary checklist of the orchids occurring in Chile, based on historical and recently published literature. Data compilation was assisted by using databases available on the Web (IPNI, W3Tropicos and KR). The list comprises seven genera ( Aa , Bipinnula , Brachystele , Chloraea , Codonorchis , Gavilea and Habenaria ) and 50 taxa (49 species and one variety), 25 of which are believed to be endemic to Chile. It includes the publication of a new combination, Gavilea feuilleana comb. nov.   © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 449−451.  相似文献   

19.
Heliosperma oliverae Niketić & Stevanović is described from Mt. Prokletije in south-west Serbia and north-east Montenegro, together with an estimation of its ecological preferences and International Union for Conservation of Nature and Natural Resources (IUCN) threat status. A map and illustration are provided. It is compared with seven closely related Balkan endemic taxa: H. macranthum Panić, H. retzdorffianum K. Malý, H. tommasinii Vis., H. insulare Trinajstić, H. chromodontum (Boiss. & Reuter) Juratzka, H. intonsum (Greuter & Melzh.) Niketić & Stevanović, and H. nikolicii (Seliger & T. Wraber) Niketić & Stevanović. An amended key to species and a table showing differences from the related Balkan taxa are also provided.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 55–63.  相似文献   

20.
Isoetes velata A. Braun is an amphibious plant with Mediterranean and Ibero-Atlantic distribution, showing marked morphological variability. Within the same geographical area, closely related restricted-range taxa are also present, including I. velata ssp. asturicense (restricted to mountainous areas of the north-west Iberian Peninsula) and I. boryana (restricted to the southern French Atlantic coast). These related taxa have unclear taxonomy and are both threatened. We performed a morphometric study of specimens of the three taxa. Our results suggest that I. velata ssp. asturicense is better considered as a distinct species, I. asturicense Laínz (Laínz), distinguishable from the other two taxa by mean megaspore length ( N  ≥ 30) < 360 µm. In contrast, our results do not support consideration of I. boryana as a separate species, and we here propose that this taxon be considered as a variety, I. velata A. Braun var. boryana M.I. Romero & C. Real stat. nov.   © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 459–464.  相似文献   

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