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The ostracod genus Bennelongia De Deckker & McKenzie, 1981 occurs in Australia and New Zealand. We redescribe B. nimala from the Northern Territory and describe six new species from Western Australia belonging to the B. nimala (five species) and B. triangulata sp. nov. (one species) lineages: B. tirigie sp. nov., B. koendersae sp. nov., B. pinderi sp. nov., B. muggon sp. nov., B. shieli sp. nov. and B. triangulata sp. nov. For six of these seven species, we could construct molecular phylogenies and parsimonious networks based on COI sequences. We tested for specific status and for potential cryptic diversity of clades with Birky’s 4 theta rule. The analyses support the existence of these six species and the absence of cryptic species in these lineages. Bennelongia triangulata sp. nov. is a common species in the turbid claypans of the Murchison/Gascoyne region. Bennelongia nimala itself is thus far known only from the Northern Territory. Bennelongia tirigie sp. nov., B. pinderi sp. nov. and B. muggon sp. nov. occur in the Murchison/Gascoyne region, whereas B. koendersae sp. nov. and B. shieli sp. nov. are described from the Pilbara. With the six new species described here, the genus Bennelongia now comprises 31 nominal species.
Elevational gradients in high mountain ranges are particularly suitable to study and understand patterns and drivers of plant community diversity and composition, yet there are only few studies that explicitly addressed this topic for the European Alps. Here we analysed an elevational gradient in grasslands of the Gran Paradiso National Park (NW Italy) from c. 1,700 to 3,100 m a.s.l. We recorded vascular plant species composition in 13 100-m² plots, each with two series of nested subplots from 0.0001 to 10 m², as well as a set of environmental parameters (topography, soil). Beta-diversity was assessed via the z-values of power-law species-area relationships, both across all plot sizes and from one plot size to the next bigger one. Diversity-environment relationships were assessed with multi-model inference based on Akaike information criterion (AIC), while scale dependence in z-values across plot sizes was analysed with an ANOVA. Life forms and three major functional traits (specific leaf area = SLA, canopy height, seed mass) were derived from trait databases to calculate fractions of life forms and community-weighted means for the metric traits. Species richness on 100 m² ranged from 17 to 65, with a mean of 43.5. The z-values were within a typical range known for European grasslands (mean: 0.227), with non-significant scale dependence. The importance of environmental factors for richness changed across grain sizes, with inclination (positive effect), mean soil depth and soil skeleton content (both: negative effect) being most influential at grain sizes of 0.0001–1 m². By contrast, soil pH was most important (with a unimodal relationship) for 10 and 100 m². After account-ing for the other environmental factors, elevation showed a moderate unimodal relationship only for the two largest grain sizes. By contrast, functional composition showed strong and mostly significant rela-tionships with elevation: hemicryptophytes and geophytes became rarer and chamaephytes more fre-quent, while community-weighted means of SLA, canopy height and seed mass decreased. Our findings highlight the scale dependence of biodiversity patterns, thus pointing to the need of multi-scale sampling to reach comprehensive understanding. Further, we could provide one of the first documentations of biodiversity and functional composition along an elevational gradient in the Alps, some in agreement with expectations, others not. This suggests that more extensive studies with a similar design in this and other regions of the Alps could be a valuable contribution to the understanding of how environmental factors drive components of biodiversity as well a functional community assembly.
A new species of Ctilodes Murray, 1864 (Coleoptera: Nitidulidae) was recovered in material from Vietnam during a large study of Carpophilinae. A description and detailed diagnosis of Ctilodes clinei Powell and Duffy new species is presented here along with a key to identify all currently known species of Ctilodes.
Termites are important ecosystem engineers of the savanna biome, with the large mounds of fungus-cultivating termites being sources of habitat heterogeneity and structural complexity in African savanna landscapes. Studies from different localities throughout Africa have shown that termite mounds have a strong influence of diversity and composition of plant communities. However, most research has been conducted only at the local scale, and integrating knowledge across Africa is hampered by different methodology of studies and differing environmental context. Little is known about the variation in vegetation composition on termite mounds compared to the surrounding savanna at the regional scale and at the landscape scale, and the main determinants of plant communities on mounds are yet to be ascertained.
This thesis aimes at better understanding the influence of termite mounds on vegetation compared to the surrounding savanna across spatial scales. Three research projects analyse vegetation data and soil data from paired mound and savanna plots in West Africa. The first project examines the influence of termite-induced heterogeneity on plant diversity and vegetation composition at a regional scale, following a bioclimatic gradient from the Sahel of Burkina Faso to the Sudanian vegetation zone in North Benin. The second Project analysed variation of vegetation on and off mounds at the landscape scale in Pendjari National Park, North Benin. The third is a monitoring study over the course of two years, exploring dynamics of juvenile woody plant communities on mounds and in the surrounding savanna at a local scale. The thesis thus provides the first comparative quantitative analysis across scales of mound and savanna vegetation and the drivers of the mound–savanna difference in vegetation.
Synthesizing across scales, its results confirm that termite mounds strongly contribute to savanna plant diversity, even though mounds are not generally more species rich than the surrounding savanna. Variation in mound vegetation is much higher along climatic and soil gradients than previously acknowledged. Mound vegetation differs from the surrounding savanna in the whole study area and in each sampled savanna type, with the strongest differences occurring at the most humid study sites. A large proportion of the differences between mound and savanna vegetation is explained by clay enrichment and related soil factors, such as cation concentrations. Plants on mounds thus benefit from favourable soil conditions, including higher fertility and higher water availability, which is also mirrored by the higher abundance and basal area of juvenile woody plants found on mounds. The variation in mound vegetation between study sites across scales results in part from local differences in soil composition and from climatic differences that influence the regional distribution of species. Different sets of characteristic mound species are identified in each project. Specific plant families and traits like succulency, lianescence, and adaptations to zoochory are found to be overrepresented in mound communities.
In addition to the findings in this thesis, remaining parts of the variation in mound vegetation between study sites could likely be explained by investigating further factors. Specifically, mound vegetation depends on habitat context, which includes available species pools, spatial distribution of mounds, biotic interactions with dispersers and herbivores, fire, and also anthropogenic influence. The high proportion of species with adaptations to zoochory found on mounds, for example, indicates that animal dispersers should be of particular importance for vegetation on termite mounds. Herbivory and fire regime, which are known to contribute to the diversity and community composition of the mound–savanna system, also show strong local variation, not least because of anthropogenic influence.
In conclusion, termite mounds play a crucial role in maintaining heterogeneity and plant diversity in the savanna across scales. Ecosystem services provided by termites, especially considering long-term effects on soil fertility and ecosystem resilience, are most likely undervalued. Mounds should be considered in management plans from local to regional, transnational scales as a matter of course, accompanied by further research on the role of termite mounds in savanna ecology on a longer temporal scale. The research presented here thus provides a basis for future studies on termite mound vegetation that should specifically consider the biotic and abiotic context of the mound–savanna system.
Dynamics of juvenile woody plant communities on termite mounds in a West African savanna landscape
(2014)
Termites are keystone species in savanna ecology, and their mounds are thought to be an important source of habitat heterogeneity and structural complexity of the savanna. Macrotermes termitaria have been shown to allow woody plant colonisation of landscapes otherwise dominated by C4 grasses. In this study, we assess how resource-rich Macrotermes mounds affect juvenile woody plant and non-woody plant species diversity, community composition, biomass and population dynamics. We repeatedly sampled paired termite mound and savanna plots in Pendjari National Park (Sudanian vegetation zone, North Benin, West Africa) over the course of two years. Despite considerable overlap in their species pools, plant communities of mound and savanna plots were clearly separated in ordinations. Species richness and diversity of juvenile woody plants was consistently higher on termite mounds, while no differences could be detected for non-woody plants. Evenness of juvenile woody plants was generally lower on mounds, whereas density and basal area were higher on mounds. In contrast, we did not detect any influence of the mound microhabitat on colonisation, mortality and turnover of woody juveniles. Therefore, we suggest that differences in the communities on and off mounds should be strongly influenced by directed diaspore dispersal through zoochory.
It is common knowledge that plants have been the world-wide most important source of medicines and that they still play this role in developing countries. However, up to now, complete lists of medicinal and aromatic plants (MAP) exist for comparatively few countries. A review of all lists know to the authors reveals the following results: A total of 20.7 % of the plant species analyzed by either publications or own research are or were used as MAP. However, regarding single countries, the differences are considerably high. Absolutely leading the list are China (36.2 %), Burkina Faso (35.2 %) and the Korean Republic (34.5 %). Also ahead of other countries or regions are the North of Benin (32.8 %) and the entire Pakistan (30.3 %). Still above average rank Great Britain (26.7 %) and Nepal (23.3 %), while the figures for Bul¬garia (21.0 %), Germany (20.2 %) and France (19.4 %) almost represent the average. Jordan (17.3 %), Vietnam (17.1 %), Sri Lanka (16.6 %), India (16.1 %) and Thailand (15.5 %) rank slightly beneath. Clearly below the average are the percentages of MAP for Hungary (12.2 %) and the USA (11.8 %). The average numbers of MAP in the Philippines (9.5 %) and Malaysia (7.7 %) fall far behind. Calculated on a worldwide scale, every fifth plant can be regarded as MAP. This number matches that from Bulgaria, France and Germany. In northern Benin, Burkina Faso, Korea, China and Pakistan, however, every third plant is or was used as MAP, whereas in Hungary and the USA only every eighth plant can be regarded as MAP. This number drops even further for the Philippines ore Malaysia where only every tenth or thirteenth plant can be attributed to medicinal or aromatic use. These differences might be due to various factors. A geographical component of the results is obvious: in most cases geographically close countries show similar percentages. A correlation between the total number of species and the fraction of those used as MAP cannot be confirmed. The countries with percentage of MAP > 30 % in common show that they belong either entirely (Burkina Faso, Benin) or at least in their rural areas to the poorest countries of the world so that it is (was) impossible for the majority of the people to buy "modern" MAP. In those countries the number of traditional healers outnumbers largely the number of modern doctors. Therefore, the tradition of folk medicine was maintained until today. Additionally, China, Korea and partially Pakistan have a very old and well documented tradition of folk medicine. Due to this documentation even in areas where today "modern MAP" are used, the knowledge was not lost. In neighboring countries or regions, which differ with respect to a more arid or a more humid climate, for the arid country (region) more MAPs are reported than for the humid one. The potential reasons for this phenomenon are discussed in the paper. For many countries the percentage given for MAP in literature is too low. But even these low values represent a striking argument for the importance of a world-wide conservation of biodiversity.
The continuous decline in biodiversity in some European landscapes has led recently to the (re-) implementation of low-intensity grazing systems as an alternative to more cost-intensive conservation practices. This approach aims at developing habitat complexes comprising various successional stages and increasing plant species diversity on local (a-diversity) and landscape scales (b-, y-diversity). The primary objectives of this review were to uncover ecological processes in which large domestic herbivores (cattle, equids, sheep, goats, pigs) have a key function in affecting plant diversity and to provide a framework for future research and conservation practices. The reviewed literature covers a wide range of ecosystem types in various temperate regions of Europe with a main focus on recent results from Central Europe. Low-intensity grazing enhances existing environmental gradients and generates manifold disturbance patterns on various spatial scales resulting in high habitat diversity. Livestock trampling has a so far underestimated impact on plant species composition and richness. Additionally, selective herbivore behavior facilitates the coexistence of plant species representing different functional types including a considerable number of threatened and grazing-sensitive species. Co-occurrence of progressive and regressive successional processes on low-intensive pastures results in a high b- and y-diversity, an effect that has been observed soon after the (re-)implementation of grazing. Persistence of speciespoor successional stages of dominant competitive graminoid and herb species can in many cases be inhibited by grazing. Large domestic herbivores serve as effective vectors for the dispersal of diaspores, thus improving the connectivity of isolated plant populations. There is a combined effect of diaspore dispersal and microsite creation which can increase the probability of diaspores to successfully germinate and establish. Overall, low-intensity grazing represents a highly flexible concept to maintain and restore plant diversity in cultivated landscapes; general management implications are given.
Results of an Odonata survey carried out in the peatlands of Central Kalimantan, Indonesia, in 2012
(2014)
The results of a survey of Odonata (dragonflies and damselflies) in the peat lands of Central Kalimantan, Indonesia, in 2012 are presented. Fifty four species of Odonata found in the area in June-July 2012 are listed, along with brief notes and the locations in which they were found. Of the species found, twelve had not been recorded in Central Kalimantan previously, and of these at least four are completely new to science. Six species, originally described from Central Kalimantan and not recorded any- where since 1953, were rediscovered. At least sixteen of the species found during the survey are considered to be of conservation concern. The discovery of at least four new species to science in a relatively short survey indicates a high probability of occurrence of many more species that are awaiting discovery, and that many un-discovered species may be lost or highly threatened because of the rapid demise of peat swamp forest habitats. A checklist of the Odonata known from Central Kalimantan is provided in an appendix.
The study of the Portuguese marine ichthyofauna has a long historical tradition, rooted back in the 18th Century. Here we present an annotated checklist of the marine fishes from Portuguese waters, including the area encompassed by the proposed extension of the Portuguese continental shelf and the Economic Exclusive Zone (EEZ). The list is based on historical literature records and taxon occurrence data obtained from natural history collections, together with new revisions and occurrences. It comprises a total of 1191 species, distributed among 3 superclasses, 4 classes, 42 orders, 212 families and 617 genera. If considering only the EEZ and present territorial waters, this list represents an increase of 230 species (27.8%) and of 238 species (29.0%), when compared to the information available in FishBase (2012) and in the last checklist of marine and estuarine fishes of Portugal (1993), respectively. The order Perciformes shows the highest diversity, with 54 families, 162 genera and 299 species. Stomiidae (80 species), Myctophidae (71 species) and Macrouridae (37 species) are the richest families. From the listed species, 734 are present off mainland Portugal, 857 off the Azores and 766 off Madeira. Within the limits of the examined area, three species are reported for the first time in mainland Portugal and twenty-nine records are identified as doubtful. A total of 133 species have been recorded from the extended Portuguese continental shelf (2 off mainland Portugal, 117 off the Azores and 14 off Madeira), two of which are common to the Azores and Madeira extensions. Biogeographically, the Atlantic group is the most important (548 species – 46.01%), followed by the Lusitanian group (256 species – 21.49%), the African group (71 species – 5.96%), the Boreal group (34 species – 2.85%), the Mediterranean group (31 species – 2.60%), the Macaronesian group (21 species – 1.76%), the Atlantic/African group (19 species – 1.60%) and the Mediterranean/African and the Arctic groups, each with only 1 species (0.08%). Regarding the preferences for vertical habitat, the demersal fishes are the most important group (305 species – 25.61%), followed by the mesopelagic group (228 species – 19.14%), the bathypelagic group (164 species – 13.77%), the benthopelagic group (147 species – 12.34%), the bathydemersal group (115 species – 9.66%), the reef-associated group (88 species – 7.39%), the pelagic group (74 species – 6.21%), the epipelagic group (58 species – 4.87%) and 1 species (0.08%) of the benthic group. The oceanic habitat is the best represented group comprising 446 species (37.45%), followed by the shelf group (199 species – 16.71%), the slope group (164 species – 13.77%), the inner shelf group (89 species – 7.47%), the coastal group (70 species – 5.88%), the outer shelf group (29 species – 2.43%) and the oceanic/shelf group (7 species – 0.59%).
The ostracod genus Bennelongia De Deckker & McKenzie, 1981 is endemic to Australia and New Zealand. Extensive sampling in Western Australia (WA) revealed a high specific and largely undescribed diversity. Here, we describe seven new species belonging to the B. barangaroo lineage: B. timmsi sp. nov., B. gnamma sp. nov., B. hirsuta sp. nov., B. ivanae sp. nov., B. mcraeae sp. nov., B. scanloni sp. nov. and B. calei sp. nov., and confirm the presence of an additional species, B. dedeckkeri, in WA. For five of these eight species, we could construct molecular phylogenies and parsimonious networks based on COI sequences. We also tested for cryptic diversity and specific status of clusters with a statistical method based on the evolutionary genetic species concept, namely Birky’s 4 theta rule. The analyses support the existence of these five species and a further three cryptic species in the WA B. barangaroo lineage. The molecular evidence was particularly relevant because most species described herein have very similar morphologies and can be distinguished from each other only by the shape, size and position of the antero-ventral lapel on the right valve, and, in sexual populations, by the small differences in shape of the hemipenes and the prehensile palps in males. Four species of the WA B. barangaroo lineage occur in small temporary rock pools (gnammas) on rocky outcrops. The other four species are mainly found in soft bottomed seasonal water bodies. One of the latter species, B. scanloni sp. nov., occurs in both claypans and deeper rock pools (pit gnammas). All species, except for B. dedeckkeri, originally described from Queensland, have quite clearly delimited distributions in WA. With the seven new species described here, the genus Bennelongia now comprises 25 nominal species but several more await formal description.