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1.
Six new species of Melastomataceae from Ecuador are described: Miconia renneri from the montane forests in north-western Ecuador; Clidemia longipedunculata from the lowland rainforest in eastern Ecuador, and Miconia oellgaardii, Brachyotum johannes-julii, B. russatum , and B. incrassatum from the upper montane forests and plramos in southern Ecuador.  相似文献   

2.
Carabidae beetles (Coleoptera) were sampled by flight intercept traps (FITs) and hand sampling in the understory of a lowland rainforest in eastern Ecuador. Sampling occurred in June and July of 2011 and 2012 at 24 sites within temporarily flooded forest (FP) and non-flooded terra firme (TF) forest. A total of 674 Carabidae (excluding Cicindelinae) individuals, representing 18 tribes, 50 genera and 133 morphospecies, were collected. Significantly more individuals were collected by hand compared to FITs, particularly by hand in FP forests. After correction through sample-based rarefaction there are no significant differences in species richness between sampling methods and forest types. Ordination and dissimilarity analysis show FITs and hand sampling target different portions of the Carabidae community. Understanding sampling biases for various sampling methods and how it may be affected by forest type will result in more accurate and efficient surveys in tropical forests.  相似文献   

3.
Aim Andean forests are known to be a major diversity hotspot for vascular plants and vertebrates, but virtually nothing is known about the diversity of arthropods. We examined whether montane rain forests in southern Ecuador are also a diversity hotspot for arthropods, and chose geometrid moths as a model group. Location The study area in southern Ecuador (Province Zamora‐Chinchipe, 79° W, 04° S) covers c. 40 km2, with 39 collecting sites within an elevational range of 1040–2677 m a.s.l. Thirty‐five of the sites were situated in an area c. 2.5 km2. Additional qualitative sampling was carried out in the same area and up to an elevation of 3100 m. Methods Nocturnal moths were collected quantitatively and qualitatively using portable light towers consisting of two 15 W fluorescent tubes, and diurnal moths were collected qualitatively using an insect net. Insects were sampled in six fieldwork periods in the years 1999–2003. As diversity measures, Fisher's alpha of the log‐series distribution as well as eight estimators of total species richness were applied. Results A total of 1266 species were recorded, 63% of which were identified to named species, whereas the remainder are likely to include many undescribed species. Quantitative samples at light towers collected 35,238 specimens representing 1223 species. The extrapolated species number for these data is 1420 (incidence coverage estimator). Twenty‐one additional nocturnal species and 22 exclusively diurnal species were sampled qualitatively at elevations between 1040 and 3100 m. The pooled value of Fisher's alpha for all quantitative samples is 246 ± 3. Main conclusions The diversity of Geometridae documented here is much higher than anywhere else in the world, even without the inclusion of additional species from adjacent lowland rain forests. The number of recorded species in this small area corresponds to more than 6% of the known world fauna of geometrid moths. Our study emphasizes the importance of protecting the remaining montane Andean rain forests. For setting priorities in conservation, more studies on insect diversity are urgently required in other regions of the Andes, since montane forests are being destroyed at an alarming rate.  相似文献   

4.
We tested two methods to obtain more complete species inventories in surveys of lichen biodiversity. The first was to employ eight lichenologists (all experienced, some specialists) acting as individuals in parallel in a competitive survey. The second was to organize those lichenologists into two competing teams. We show that overall recorded biodiversity is distinctly higher than the part of lichen biodiversity recorded by each single lichenologist (45–66%) or team (79–83%). Use of these methods in a survey of epiphytic and epixylic lichens resulted in a list containing 112 species in 1 ha, 192 species in 12.5 ha and 212 species for 30 km2 of lowland floodplain old‐growth forest in southeastern Czech Republic. Eleven recorded species are new to the country; four are rediscovered after more than 50 years. In comparison, few previous surveys of mixed montane forests in the same region have yielded more than 200 species, even though it is certain that those forests have greater lichen diversity than our lowland forest.  相似文献   

5.
Over a period of five years parasitological surveys were carried out on the freshwater fish fauna in the eastern Caprivi which included the upper Zambesi River, a section of the Chobe and Kwando Rivers, and vast swampy areas. This area is well known for its wide variety of indigenous fish and has so far not been influenced in any way by introduced alien fish species. In these surveys 45 different fish species of 12 families were examined. This paper reports on the parasites of the generaTrichodina andHemitrichodina of the eastern Caprivi. A total of 15 species of parasites were recorded of which nine are new species described here-in. The list of host records of known species are expanded and an evaluation of host specificity based on information recorded in this survey as well as previously published data from southern Africa is provided.  相似文献   

6.
Termites are ecosystem engineers that play an important role in the biotransformation and re‐distribution of nutrients in soil. The dry forests are endemic repositories, but at same time, they are most threatened by extensive livestock and crop farming, fires, and climate change. In Colombia, the best‐protected dry forests are located in the north. The termite fauna of dry forests are poorly known. The aim was to identify the termite species occurring in tropical dry forests of the Colombian Caribbean coast in relation to diet and precipitation, temperature, elevation, and soil properties. A total of 32 species in 1,103 occurrences were found. Termitidae accounted for 78% of the species richness with the Anoplotermes‐group, Microcerotermes, and Nasutitermes being the dominant genera. Differences in species composition and abundance were found across sites. These differences may be linked to anthropogenic disturbance and polygyny and polydomy. Strikingly, our highest elevation site (334 m) had the highest species richness much higher than the two lower elevation sites. This implies an inversion of the common elevation‐diversity gradient, also found for termites which can be explained by increasing precipitation with elevation in the dry forest. An analysis of termite species richness at the global scale confirms that termite species richness correlates positively with rainfall. Hence, rainfall seems to positively affect termite diversity. In line, the studied Colombian tropical dry forests had low diversity compared to rain forests. A decline of species‐rich soil‐feeding termites with increasing aridity may explain why the highest termite diversity occurs in humid tropical rain forests. Abstract in Spanish is available with online material.  相似文献   

7.
8.
The value of conifer-dominated plantation forestry for heathland carabids is examined, in Breckland, eastern England. Historically dominated by heathland habitats supporting scarce species of restricted distribution within the UK, approximately 47% of Breckland was afforested in the early 20th century. The carabid fauna of this forest, previously little known, was sampled by intensive pitfall trapping, and results compared to samples from heathland and arable. The results affirm that Breckland supports many range-restricted carabid beetles, including scarce species restricted to lowland heathland or sandy habitats. Approximately half of the heathland-associated species, and also half of the Nationally Scarce carabid species recorded in Breckland, were found within the forest landscape. Carabid species composition differed between closed-canopy forest, heathland and arable, while open forest habitats (clear-felled stands, young restocked stands, and track margins) contained a diverse fauna with elements from all habitats. The proportion of heathland-associated species was significantly greater in open forest habitats than in closed-canopy forest and was similar to that of heathland assemblages. Wing morphology did not differ between heathland species solely recorded from heathland and those also recorded in the forest. Nationally Scarce species from the forest had a wider UK distribution than those recorded only from heathland. Our study shows that, within conifer forest planted in lowland heathland areas, open habitats provided by trackway networks and clear-felling management can have significant value for the conservation of open-ground carabids, including species of conservation importance.  相似文献   

9.
Here we describe and illustrate a new parasitoid wasp species, Lathrolestes gauldi sp. n. from the lowland rainforest of eastern Ecuador and provide a key to the Neotropical species of the genus. This is the first record of the subfamily Ctenopelmatinae from Ecuador.  相似文献   

10.
The results of small mammal inventories at 11 sites ranging from sea level to 1000 m a.s.l. on the Masoala Peninsula in northeastern Madagascar are presented. The Rodentia and Lipotyphla (ex Insectivora) of this peninsula, that contain extensive areas of lowland rainforest and some montane habitat, were previously poorly known. Fifteen endemic (5 rodents and 10 tenrecs) and 2 introduced species [Rattus rattus (Linnaeus, 1758) andSuncus murinus(Linnaeus, 1766)] were recorded. Species diversity in the lowland forests was reduced as typically found in other lowland sites in the eastern humid forest, while that of the lower montane zone was notably low as compared with other nearby large forested areas to the interior of the peninsula. Several ideas are presented to explain this difference, including the peninsula effect.  相似文献   

11.
Landscape diversity patterns and endemism of Araceae in Ecuador   总被引:1,自引:0,他引:1  
Araceae is one of the largest herb families in tropical America, but its patterns of diversity and endemism are poorly known. We used predictive distribution modelling in GIS to study Araceae richness on a landscape scale in Ecuador. Modelling was based on georeferenced herbarium collections with humidity and mean annual temperature as climatic variables. Variation partitioning using multiple regression showed that humidity and altitude were main factors in explaining Araceae diversity patterns. Endemism was less well explained by present climatic factors. Unlike common diversity patterns of herbs or epiphytes, Araceae richness was highest in the eastern (Amazon) lowland rain forest with a secondary centre on the Andean foothills of northwestern Ecuador. The peak in endemism was on the western slopes of the Andes, corresponding to areas that have been severely affected by human activities and deforestation. Eastern lowland (Amazonian) forests were poor in endemic Araceae.  相似文献   

12.
Aim  African forests are divided by an arid corridor which runs from the Horn of Africa to the Namib Desert. Several forest species occur in the forests of eastern Africa as well as in the Guineo-Congolian forest block. We evaluate the possibility that such species may have crossed the arid corridor along a route through the Kenyan Highlands and down the eastern drainages during climatologically favourable periods in the past.
Locations  Eastern Africa, Ivory Coast.
Methods  We used the termite species Schedorhinotermes lamanianus (Sjöstedt). This species occurs in lowland forests and woodland throughout Africa south of the Sahara. We sampled termites from 12 populations. We evaluated the differentiation between populations using amplified fragment length polymorphisms as well as morphometrical measurements.
Results  Genetic and morphometrical analysis demonstrated substantial differentiation between populations west and east of the arid corridor in Kenya. To the east of this corridor we found an increase of morphological distance with geographical distance. Schedorhinotermes lamanianus occurs not only along the coast but also at isolated locations (e.g. ground-water forests in foothills) within the arid hinterland.
Main conclusions  We interpret these populations as remnants of a wider distribution during wet climatic periods. At these times, populations of S. lamanianus were apparently able to establish along extensive gallery forests protruding into the arid belt of the Kenyan hinterland. There have been no connections between populations of this species east and west of the arid corridor across the Kenyan Highlands.  相似文献   

13.
Two species of Gesneriaceae are described:Alloplectus purpureus from the lower montane forests of northwestern Ecuador and adjacent Colombia andColumnea nematoloba from the lowland rain forests of western Colombia. The first with its fimbriate calyx lobes is probably nearest toAlloplectus sprucei, occurring in the same region but mostly at lower elevations. The second is in a group with two recently described species from western Ecuador and Colombia,Columnea fililoba andC. incredibilis, all having filiform corolla lobes.  相似文献   

14.
The BOU Indonesia Expedition, with BirdLife International, carried out surveys on the Moluccan Islands of Buru and Halmahera in 1994-96 as part of a process of protected area identification. Data on resident forest birds were collected during ten-minute sampling periods at points along altitudinal gradients, in primary and modified forests and in rainforests on different geology. While all species ever reported from Halmahera have been recorded down to near sea level, many of the forest birds of Buru, including a number of restricted-range and endemic species, are largely confined to montane forest, and only common above 800–900 m altitude. The existence of a distinct montane bird community on Buru, but not on Halmahera, is attributed to the relatively large, continuous area of forest at high altitude on this island. Forest on Halmahera at such altitudes is limited and fragmented. While most species survive in modified forests, some were significantly rarer in this habitat and may depend on adjacent areas of primary forest. Mangroves supported impoverished forest bird communities, typically of more adaptable species. On Halmahera, rainforest on ultrabasic rock appears to be impoverished when compared with rainforest on other rock formations, in particular supporting very low numbers of two species of threatened parrot. Implications for conservation concern lowland forests on Halmahera. Despite the surveys, a number of species of conservation concern that occur on Halmahera and Buru still remain largely unknown.  相似文献   

15.
Distributions, endemism and diversity among East African linyphiids are analysed and discussed in relation to other forest organisms and the environmental history of eastern African. A total of 231 species are reported from eastern Africa, of which 14 are confined to the Afroalpine region and 114 species to moist forests. Only 12 of the latter are widely distributed. The rest are only known from one or two localities. Information on habitats and distributions of all species is tabulated. Few species are shared between East African mountains and there are no detectable gradients of species diversity between mountains. There is, however, a gradient of decreasing species diversity from high latitudes to the Equator. Vicariance patterns are demonstrated for Elgonia, Ophrynia and Callitrichia in the Eastern Arc Mountains, Tanzania—areas that also hold the highest degree of endemism (> 80% on individual mountains) among linyphiids. The many endemic species on nearby mountains suggest that intermontane dispersal (ballooning) is rare or non-existent. There is no evidence for a distinction between highland and lowland linyphiid faunas, but altitudinal segregation of single species is demonstrated. The question of the reality of highland and lowland faunas cannot be solved by studying the altitudinal distribution of single species. Phylogenetic relationships must be taken into consideration to determine where sister-groups/species are located (lowland or highland).  相似文献   

16.
The Volga, the largest river in Europe, has experienced multiple stressors from human activities. Recently we showed that its upper course (about 500 km, from its source to Tver) still has large sections with low impact and a natural type-specific potamal flora and fauna. Our present research in the East European lowlands aim to define reference conditions for mid-sized to large lowland rivers in order to build a basis for future management and conservation. Three monitoring sites were selected based on the results from intensive sampling in 2005. In subsequent field campaigns between 2006 and 2010 regular surveys were carried out each year in summer and additional ones in spring. A taxon-rich macroinvertebrate fauna, including several rare potamal relict species, was recorded and the data was used to provide an overview of annual and interannual variation in community indices and metrics. The conditions described for the headwaters of the Volga River system can be used as a reference state for medium-sized and large lowland rivers in regions where reference sites of these types are lacking.  相似文献   

17.
The Indonesian province of East Kalimantan is home to some of the largest remaining contiguous tracts of lowland Dipterocarp forest on the island of Borneo. Nest surveys recently conducted in these forests indicated the presence of a substantial population of Eastern Bornean orangutans (Pongo pygmaeus morio) in the Berau and East Kutai regencies in the northern half of the province. The Sangkulirang Peninsula contains extensive limestone karst forests in close proximity to the lowland Dipterocarp forests inhabited by orangutans in these regencies. Orangutans have been sighted in these limestone karst forests, but the importance of this forest type for orangutans has been unclear. Therefore, we conducted 49 km of nest surveys in limestone karst forest to obtain the first quantitative estimates of orangutan densities in this habitat, and walked 28 km of surveys in nearby lowland Dipterocarp forests for comparison. We also gathered basic ecological data along our transects in an attempt to identify correlates of orangutan abundance across these habitat types. Undisturbed limestone karst forests showed the lowest orangutan densities (147 nests/km(2), 0.82 indiv/km(2)), disturbed limestone forests had intermediate densities (301 nests/km(2), 1.40 indiv/km(2)), and undisturbed lowland Dipterocarp forests contained the highest density (987 nests/km(2), 5.25 indiv/km(2)), significantly more than the undisturbed limestone karst forests. This difference was not correlated with variation in liana abundance, fig stem density, or stump density (an index of forest disturbance). Therefore, other factors, such as the relatively low tree species diversity of limestone karst forests, may explain why orangutans appear to avoid these areas. We conclude that limestone karst forests are of low relevance for safeguarding the future of orangutans in East Kalimantan.  相似文献   

18.
Abstract. Following the recognition of a discrete East African lowland amphibian fauna (Poynton, 1990), this paper investigates the possible recognition of an Afromontane amphibian fauna in southern Africa. Species turnover in a transect from the Mozambique/KwaZulu-Natal border area through Swaziland to the Eastern Transvaal highveld is described, and compared with previously described transects through Mozambique to Zimbabwe, and KwaZulu-Natal to the central Free State. Turnover in the Swaziland transect shows two peaks. Marked turnover at the edge of the interior plateau is taken to indicate an eastern border of an Afromontane fauna; the other peak, at the western edge of the coastal lowland, is taken to mark the border of an East African lowland fauna. A transition zone with a transitional assemblage occurs on the plateau slopes between the two borders. The Zimbabwean transect shows a similar pattern. The KwaZulu-Natal to Free State transect shows a broad transition from upland to lowland assemblages, which parallels the extensive intermingling of upland and lowland floristic elements in that area. A north-south turnover across the three transects shows northern species becoming progressively excluded from highland areas as they extend southwards, while southern species become limited to the highlands as they extend northwards. The cohesive north-south turnover pattern is consistent with the idea of a single Afromontane biogeographical unit, which can be related to a tropical East African lowland unit through a complex pattern of species turnover.  相似文献   

19.
Distribution patterns of plant species endemic to Ecuador and adjacent parts of southern Colombia and northern Peru are analysed on the basis of information in the Flora of Ecuador. A total of 827 restricted-range species were found, many of which are known from extremely small areas, often only one or a few localities. A total of 27% of the species treated in the Flora of Ecuador are endemic to that country. The overall proportion of endemic and restricted-range species is greater in the Andes than in the lowland areas on either side of these mountains; particularly the southern Andes appears to be very rich in endemic species. Spatial analysis of distribution data results in the recognition of 15 floristic elements and 18 geographical endemism regions in Ecuador, the characteristics of which are discussed. Comparison with distribution patterns of restricted-range bird species show a general correspondence, with the main difference that birds tend to be more widely distributed than plants along the Andes. Comparison of the results with the location of national parks and other protected areas shows that the endemic floras in the northern and eastern parts of the country are much better protected than those of the southern and western parts.  相似文献   

20.
Details are presented of the composition of the diet of eastern lowland gorillas, derived mainly from a study of their fresh trails and fecal analysis, during the course of an entire year in the tropical lowland forests of the Itebero region, Zaire. Gorillas ate 194 plant foods from 121 species and 45 families. They consumed 48 species of fruits; and 89% of fecal samples contained fruit seeds, but fruits were a relatively small part (25%) of the total number of food items. The composition of their diet changed seasonally. When consumption of fruit decreased in the long rainy and the long dry seasons, the gorillas ate, in addition to Zingiberaceae and Marantaceae, many kinds of leaf and bark, which may be an important buffer against the shortage of fruits. Gorillas also fed regularly on ants (Ponerinae), and the frequency of consumption showed small seasonal variations. From a comparison of diet composition, eastern lowland gorillas appeared to be intermediate between the other two subspecies. The choice of food showed differences in preference of fruits and insects between subspecies and may reflect high similarities within subspecies in lowland and montane forests.  相似文献   

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