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Cumulative species description curves since 1758 are given for all termites of the world and for each biogeographical region (Australian, Ethiopian, Nearctic, Neotropical, Oriental, Palearctic, and Papuan). A cumulative description curve is also given for world genera. Estimation by maximum likelihood using the Michaelis-Menten model suggests a maximum of 5366 ± 175 species (p < 2.2E-16) and 704 ± 77 genera (p < 4.387E-13). Model fitting was poor for most individual biogeographical regions, with the exception of the Ethiopian region (estimate = 1295 ± 57 species, p < 2.2E-16). World War I and World War II had marked negative impacts on termite description rates. Data from China was treated separately due to the atypical rate of description of new termites in that country during the last two decades of the 20th century.

The ranges and abundances of species that depend on freshwater habitats are declining worldwide. Efforts to counteract those trends are often hampered by a lack of information about species distribution and conservation status and are often strongly biased toward a few well-studied groups. We identified the 3,906 vascular plants, macroinvertebrates, and vertebrates native to California, USA, that depend on fresh water for at least one stage of their life history. We evaluated the conservation status for these taxa using existing government and non-governmental organization assessments (e.g., endangered species act, NatureServe), created a spatial database of locality observations or distribution information from ~400 data sources, and mapped patterns of richness, endemism, and vulnerability. Although nearly half of all taxa with conservation status (n = 1,939) are vulnerable to extinction, only 114 (6%) of those vulnerable taxa have a legal mandate for protection in the form of form.

Heterogenität von Umweltbedingungen gilt als einer der wichtigsten Faktoren für die Verteilung von Artenreichtum weltweit. Laut der Habitatheterogenität-Hypothese bieten räumlich heterogenere Gebiete eine höhere Vielfalt an Umweltparametern und weisen mehr Refugien und Möglichkeiten zur Isolation und Radiation auf. Dadurch begünstigen sie Koexistenz, Persistenz und Diversifikation von Arten. Die Erforschung potentieller positiver Effekte von Heterogenität auf Artenreichtum fasziniert Ökologen und Evolutionsbiologen seit Jahrzehnten. Dementsprechend existieren zahlreiche Studien über die Bez...

Heterogenität von Umweltbedingungen gilt als einer der wichtigsten Faktoren für die Verteilung von Artenreichtum weltweit. Laut der Habitatheterogenität-Hypothese bieten räumlich heterogenere Gebiete eine höhere Vielfalt an Umweltparametern und weisen mehr Refugien und Möglichkeiten zur Isolation und Radiation auf. Dadurch begünstigen sie Koexistenz, Persistenz und Diversifikation von Arten. Die Erforschung potentieller positiver Effekte von Heterogenität auf Artenreichtum fasziniert Ökologen und Evolutionsbiologen seit Jahrzehnten. Dementsprechend existieren zahlreiche Studien über die Bez...

Chapter 1. Introduction to the world of Carabus -- Chapter 2. Ohomopterus: a species radiation with diversification of key traits for mechanical reproductive isolation -- Chapter 3. Biology of Ohomopterus -- Chapter 4. Species assemblages -- Chapter 5. Natural hybridization and reproductive isolation -- Chapter 6. Evolutionary history of Ohomopterus -- Chapter 7. Evolution of a key trait for species diversity: body size -- Chapter 8. Evolution of a key trait for species diversity: genital morphology -- Chapter 9. Overview: How does species richness increase?

7 páginas, 3 figuras, 2 tablas ; If the size dependence of species richness varies across ecosystems, it should be reflected in the size distribution of total abundance. Using a database of phytoplankton abundance, species composition and cell size from coastal, shelf and open-ocean environments, we show that the biogeographical patterns of phytoplankton size distribution in the ocean are a result of systematic changes in the relationship between species richness and cell size. Our results indicate that, regardless of the environmental conditions, population abundance decreases consistently to the –3/4 power of cell size. By contrast, marine phytoplankton diversity peaks at small sizes in oligotrophic waters but is either a log-normal function or independent of cell size in eutrophic systems. It is argued that, operating on evolutionary time scales, size-dependent biophysical constraints for resource acquisition are reflected in the size distribution of species richness and consequently in the size structure of phytoplankton communities in the ocean. These findings indicate that the way in which biological diversity changes with body size is crucial to a better understanding of the structure and functioning of microbial plankton communities and how energy flows through pelagic ecosystems ; AMT data collection was supported by the UK Natural Environmental Research Council through the Atlantic Meridional Transect consortium (NER/O/S/2001/00680). P.C. was supported by a Fulbright Postdoctoral Research Fellowship from the Spanish Ministry of Education and Science and a Marie Curie Outgoing International Fellowship from the European Union ; Peer reviewed

The ranges and abundances of species that depend on freshwater habitats are declining worldwide. Efforts to counteract those trends are often hampered by a lack of information about species distribution and conservation status and are often strongly biased toward a few well-studied groups. We identified the 3,906 vascular plants, macroinvertebrates, and vertebrates native to California, USA, that depend on fresh water for at least one stage of their life history. We evaluated the conservation status for these taxa using existing government and non-governmental organization assessments (e.g., endangered species act, NatureServe), created a spatial database of locality observations or distribution information from ~400 data sources, and mapped patterns of richness, endemism, and vulnerability. Although nearly half of all taxa with conservation status (n = 1,939) are vulnerable to extinction, only 114 (6%) of those vulnerable taxa have a legal mandate for protection in the form of formal inclusion on a state or federal endangered species list. Endemic taxa are at greater risk than non-endemics, with 90% of the 927 endemic taxa vulnerable to extinction. Records with spatial data were available for a total of 2,276 species (61%). The patterns of species richness differ depending on the taxonomic group analyzed, but are similar across taxonomic level. No particular taxonomic group represents an umbrella for all species, but hotspots of high richness for listed species cover 40% of the hotspots for all other species and 58% of the hotspots for vulnerable freshwater species. By mapping freshwater species hotspots we show locations that represent the top priority for conservation action in the state. This study identifies opportunities to fill gaps in the evaluation of conservation status for freshwater taxa in California, to address the lack of occurrence information for nearly 40% of freshwater taxa and nearly 40% of watersheds in the state, and to implement adequate protections for freshwater taxa where they are currently lacking.

The ranges and abundances of species that depend on freshwater habitats are declining worldwide. Efforts to counteract those trends are often hampered by a lack of information about species distribution and conservation status and are often strongly biased toward a few well-studied groups. We identified the 3,906 vascular plants, macroinvertebrates, and vertebrates native to California, USA, that depend on fresh water for at least one stage of their life history. We evaluated the conservation status for these taxa using existing government and non-governmental organization assessments (e.g., endangered species act, NatureServe), created a spatial database of locality observations or distribution information from ~400 data sources, and mapped patterns of richness, endemism, and vulnerability. Although nearly half of all taxa with conservation status (n = 1,939) are vulnerable to extinction, only 114 (6%) of those vulnerable taxa have a legal mandate for protection in the form of formal inclusion on a state or federal endangered species list. Endemic taxa are at greater risk than non-endemics, with 90% of the 927 endemic taxa vulnerable to extinction. Records with spatial data were available for a total of 2,276 species (61%). The patterns of species richness differ depending on the taxonomic group analyzed, but are similar across taxonomic level. No particular taxonomic group represents an umbrella for all species, but hotspots of high richness for listed species cover 40% of the hotspots for all other species and 58% of the hotspots for vulnerable freshwater species. By mapping freshwater species hotspots we show locations that represent the top priority for conservation action in the state. This study identifies opportunities to fill gaps in the evaluation of conservation status for freshwater taxa in California, to address the lack of occurrence information for nearly 40% of freshwater taxa and nearly 40% of watersheds in the state, and to implement adequate protections for freshwater taxa where they are ...

The beetle Osmoderma eremita has received much attention in the last few years, as it is among those species with the highest priority in the European Union's Habitat Directive. In this paper the species is evaluated as a potential indicator and umbrella species for the endangered beetle fauna in tree hollows. To be useful as an indicator of a species rich fauna it should be easy to inventory and be strongly correlated with the presence of other species. An umbrella species is a species which is so demanding that the protection of this species will automatically save many others. The species richness of saproxylic beetles and occupancy of O. eremita were surveyed in tree hollows in an area in southeastern Sweden by assessing presence/absence of living and dead adults (including fragments) and larvae. The species richness was higher when O. eremita was present, both at tree and stand level. Several threatened species were associated with the presence of O. eremita, whereas others did not correlate with occurrence of O. eremita. As O. eremita is easy to find and identify, it is useful as an indicator of stands with a rich beetle fauna in tree hollows. O. eremita is possible to use as an umbrella species, because if measures are taken to conserve O. eremita, many other species in the same habitat are also conserved. However, there are some beetles in tree hollows which seem to be more sensitive to habitat fragmentation than O. eremita, and may go extinct if only O. eremita is taken into consideration.