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1.
James L. Luteyn 《Brittonia》1996,48(4):605-610
The taxonomic history of Anthopterus as it relates to Themistoclesia is briefly reviewed. Anthopterus is redefined to include several species formerly placed in Themistoclesia. Two subgenera are established within Anthopterus. Anthopterus costaricensis Luteyn is described as new, and the new combination Anthopterus pterotus (A. C. Sm.) Luteyn is made. A key to the genus, a list of the species currently accepted, and brief notes on distribution and frequency are provided. Most species of Anthopterus are rare and their habitats are endangered.  相似文献   

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Conservation of biodiversity will necessitate choices among areas, taxa, and land-use patterns. Lack of data on distribution and pattern in biodiversity makes these difficult decisions even more problematic for those charged with the conservation and sustainable use of the diversity of life. Quantitative methods have promise in helping with this task in that they allow people to make their values explicit, and they also allow representation and comparison of many different types of data. In this article I examine patterns of species richness and range-size rarity, or endemism, in the Neotropics with a data set from the genusSolanum (Solanaceae). Distribution data for 180 species of forest-dwelling solanums were analyzed. Patterns of species richness, range-size rarity (endemism), and several area-selection methods were examined. Montane areas are relatively rich both in all species and in endemic species, with maximal peaks in the Andes. The peak of species richness coincides with the domain (i.e., continental) midpoint (9°30′ S latitude), suggesting that the pattern observed may be partly due to the geometry of species ranges. TheSolanum results are compared with those obtained for other taxonomic groups in the Neotropics, and problems with quantitative data sets in conservation are discussed. Collecting deficit, parochial taxonomy, and habitat destruction, both historical and current, are all factors that will affect the utility of such analyses. It is clear that if conservation is to work on the ground, we need to know more about what occurs in the montane Neotropics and that continued work at a basic taxonomic level is essential to our ultimate ability to conserve biological diversity.  相似文献   

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Many hypotheses have been proposed to explain the origin and maintenance of the Amazonian diversity with special place for the theory of isolation by rivers and a set of hypothesis related to contemporary environmental dissimilarity. We explore those hypotheses here using the biogeographic distributional patterns of dragonflies in interfluve areas of the Amazonian biome and also evaluate how differences among in dispersal capabilities between the Anisoptera and Zygoptera suborders may contribute to those patterns. We used distributional information of 392 odonate species in the Amazonian forest in a cladistic analysis of distributions and endemism and the estimated faunistic similarity among interfluves with the Sorensen index. The environmental similarity among interfluves was analysed by discriminant analysis based on eight environmental metrics. Different metrics for geographic distance (connectivity) among interfluves were evaluated and their relation to the other variables tested by the Mantel test. The number of endemic species was linearly correlated to the area of the interfluves. General endemism patterns showed consistent resemblance to those reported for vertebrates, especially the similarity among the Rond?nia and Inambari interfluves. Geographical distance has no predictive value for dragonflies distribution, but the environmental similarity is a good predictor of proportion of shared species. The low dispersal group (Zygoptera) presented more clear patterns of distribution and a lower proportion of shared species among different interfluves. The environmental similarity can be considered the determinant factor of the distribution of dragonflies, possibly due to environmental specificity evolved during a long history of some clades in this system. The low dispersal group (Zygoptera) retained more biogeographical information about possible historical factors that determine current distribution. Also, the transport of larvae by macrophyte banks, the lateral change of river courses, the reversal of the drainage basin, together with the capacity to disperse across rivers for some species may be explanations for the lack of effect of isolation by rivers, especially for Anisoptera.  相似文献   

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Chromosome numbers are reported for 36 accessions representing 31 species from nine genera of the tribe Vaccinieae, family Ericaceae. The plants are tropical and come from Southeast Asia and Central and South America. The taxonomy of the tribe is outlined in these regions. Genera are often poorly defined and taxa were chosen to reflect the range of variation of the Vaccinieae. Most Southeast Asian Vaccinium species were diploid (2 n = 24) as were those of Agapetes subgenus Agapetes (apart from the Himalayan A. flava ), Agapetes scortechinii and Costera endertii. All other accessions were found to be polyploid. The correlation between polyploidy, geographical distribution and the possession of an 'anatomical complex' of the leaf and stem in Vaccinieae of New Guinea and the neotropics is discussed.  相似文献   

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Chromosome numbers are reported for 36 accessions representing 31 species from nine genera of the tribe Vaccinieae, family Ericaceae. The plants are tropical and come from Southeast Asia and Central and South America. The taxonomy of the tribe is outlined in these regions. Genera are often poorly defined and taxa were chosen to reflect the range of variation of the Vaccinieae. Most Southeast Asian Vaccinium species were diploid (2n= 24) as were those of Agapetes subgenus Agapetes (apart from the Himalayan A. flava), Agapetes scortechinii and Costera endertii. All other accessions were found to be polyploid. The correlation between polyploidy, geographical distribution and the possession of an ‘anatomical complex’ of the leaf and stem in Vaccinieae of New Guinea and the neotropics is discussed.  相似文献   

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Vaccinium wilburii, a striking epiphyte with pink flowers and woody tuberous roots, is described, illustrated, and compared with similar species.  相似文献   

8.
James L. Luteyn 《Brittonia》1980,32(2):186-208
Recent field collecting in northwestern South America has resulted in the discovery of numerous new Ericaceae. Twelve new species ofCavendishia are herein described. Line drawings and SEM micrographs are included to illustrate certain taxonomically important features.  相似文献   

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The pollen morphology of two species of the Neotropical genus Ceratostema (Ericaceae) was examined by light, scanning and transmission electron microscopy. The Ceratostema species examined have 3-colporate pollen grains united in permanent tetrahedral tetrads that show a common condition encountered in the Ericaceae. But the septal exine was absent between two neighboring grains in each pollen tetrad of Ceratostema. The pollen tetrads without septa are the first report for the Ericaceae as well as other angiosperm families.  相似文献   

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We investigated the distribution patterns of yeast communities in freshwater lakes along a latitudinal gradient in order to evaluate yeast biogeography at intercontinental (501–8000 km), regional (0–500 km) and local (0–1 km) geographical scales. We identified 285 yeast isolates belonging to 64 species based on sequence analysis of the ITS-5.8S region and the D1/D2 domains of the large subunit of rRNA genes. Distance decay analysis showed a significant negative slope curve at the intercontinental scale. At the intercontinental and regional scales, the dissimilarity of the yeast communities was correlated with geographical distance, with community similarity decreasing with increasing distance. The physiological profiles of the yeast communities from tropical and Patagonian lakes were similar but were different from those of Antarctic lakes. This is the first report of latitudinal patterns of lake yeast diversity along a gradient extending from Antarctic to tropical environments.  相似文献   

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In a recent paper by D. R. Bellwood and C. P. Meyer ('Searching for heat in a marine biodiversity hotspot', Journal of Biogeography , 2009, 36 , 569–576), the authors had two evident objectives: (1) to disprove the theory that the geographical origins of reef organisms could be determined by locating concentrations of endemic species, and (2) to emphasize that the high diversity of the Coral Triangle was due to an accumulation of species from outside that area. With regard to the first point, no such theory had previously been proposed to my knowledge. Second, the accumulation theory was promoted without consideration of the facts supporting the centre of origin hypothesis, except to dismiss it by saying that it had its origin in pre-continental drift ideas. This short response outlines the properties and evidence for the operation of centres of origin in this region.  相似文献   

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Cavendishia osaënsis Luteyn & J. F. Morales, C. linearifolia Luteyn & J. F. Morales, C. herrerae Luteyn & J. F. Morales, and C. luteynii J. F. Morales are newly described based on recent collections from Costa Rica. Relationships within Cavendishia are discussed, and Cavendishia osaënsis and C. linearifolia are illustrated.  相似文献   

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For the first time since Drude (1897) an up-to-date key is given to all the genera of Ericaceae currently recognized in the Neotropics.  相似文献   

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Published phylogenies of two eucalypt clades, red bloodwoods Corymbia subgenus Corymbia and eudesmids Eucalyptus subgenus Eudesmia (Myrtaceae), were combined for an analysis of historical biogeographical area relationships within continental Australia. The method of paralogy‐free subtree analysis was used to eliminate geographical paralogy; the paralogy‐free subtrees were coded as characters for parsimony analysis to find the minimal and area cladogram, which proved to be informative of a continent‐wide pattern. The eucalypt fossil record and molecular dating studies allow an interpretation of the biogeographical history in terms of major vicariance events that date from the early Paleogene. The summary area cladogram shows the wet jarrah forest region of South‐West Western Australia, a region of high endemism, as the earliest to differentiate from all other areas, isolated by marine inundation across southern Australia and climatic cooling in the Late Eocene–Early Oligocene. From about this time, regionalization continued, with warmer conditions and monsoonal climate developing in central and northern Australia, and cooling in the south‐east. Northern and eastern humid and semi‐humid areas were related as a track, but with increased aridity in the interior of the continent, the monsoonal climate contracted northwards. The Australian Monsoon Tropics (AMT: Kimberley, Top End, Arnhem, Cape York and inland north‐east Queensland) differentiated from eastern areas (Queensland wet tropics to McPherson–Macleay). Our results also show all arid and semi‐arid regions as related, suggestive of a historically cohesive interior biota rather than repeated colonizations of the interior from the periphery of the continent. Climate largely differentiates hot arid areas in the north (Pilbara, Northern and Central deserts) from arid areas in the south (south‐west interzone, Wheatbelt, Goldfields and Great Victoria Desert). © The Willi Hennig Society 2010.  相似文献   

18.
The concepts of biogeographical regions and areas of endemism are briefly reviewed prior to a discussion of what constitutes a natural biogeographical unit. It is concluded that a natural biogeographical unit comprises a group of endemic species that share a geological history. These natural biogeographical units are termed Wallacean biogeographical units in honour of the biogeographer A.R. Wallace. Models of the geological development of Indonesia and the Philippines are outlined. Areas of endemism within Wallacea are identified by distributional data, and their relationship to each other and to the adjacent continental regions are evaluated using molecular phylogenies from the literature. The boundaries of these areas of endemism are in broad agreement with earlier works, but it is argued that the Tanimbar Islands are biologically part of south Maluku, rather than the Lesser Sundas, and that Timor (plus Savu, Roti, Wetar, Damar, and Babar) and the western Lesser Sundas form areas of endemism in their own right. Wallacean biogeographical units within Wallacea are identified by congruence between areas of endemism and geological history. It is concluded that although Wallacea as a whole is not a natural biogeographical region, neither is it completely artificial as it is formed from a complex of predominantly Australasian exotic fragments linked by geological processes within a complex collision zone. The Philippines are argued to be an integral part of Wallacea, as originally intended. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 193–212.  相似文献   

19.
James L. Luteyn 《Brittonia》1992,44(2):240-243
Plutarchia, a shrubby páramo genus, is here reported for the first time in Ecuador where two species are recognized: P. angulata A. C. Smith and the new P. ecuadorensis Luteyn. These two species are keyed, described, and the new species illustrated.  相似文献   

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Eight new Ericaceae (Vaccinieae) from Bolivia and Peru are described, illustrated, and discussed: Orthaea madidiensis, Themistoclesia geniculata, Themistoclesia idiocalyx, Themistoclesia siranensis, Themistoclesia tunquiniensis, Themistoclesia woytkowskii, Thibaudia acacioides, and Thibaudia yungensis.  相似文献   

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