Aim Species communities often exhibit nestedness, the species found in speciespoor sites representing subsets of richer ones. In the Netherlands, where intensification of land use has led to severe fragmentation of nature, we examined the degree of nestedness in the distribution of Orthoptera species. An assessment was made of how environmental conditions and species life-history traits are related to this pattern, and how variation in sampling intensity across sites may influence the observed degree of nestedness.Location The analysis includes a total of 178 semi-natural sites in the Pleistocene sand region of the Netherlands.Methods A matrix recording the presence or absence of all Orthoptera species in each site was compiled using atlas data. Additionally, separate matrices were constructed for the species of suborders Ensifera and Caelifera. The degree of nestedness was measured using the binmatnest calculator. binmatnest uses an algorithm to sort the matrices to maximal nestedness. We used Spearman's rank correlations to evaluate whether sites were sorted by area, isolation or habitat heterogeneity, and whether species were sorted by their dispersal ability, rate of development or degree of habitat specificity.Results We found the Orthoptera assemblages to be significantly nested. The rank correlation between site order and sampling intensity was high. The degree of nestedness was lower, but remained significant when under-and oversampled sites were excluded from the analysis. Site order was strongly correlated with both size of sample site and number of habitat types per site. Rank correlations showed that species were probably ordered by variation in habitat specificity, rather than by variation in dispersal capacity or rate of development of the species.Main conclusions Variation in sampling intensity among sites had a strong impact on the observed degree of nestedness. Nestedness in habitats may underlie the observed nestedness within the Orthoptera assemblages. Habitat heterogeneity is closely related to site area, which suggests that several large sites should be preserved, rather than many small sites. Furthermore, the results corroborate a focus of nature conservation policy on sites where rare species occur, as long as the full spectrum of habitat conditions and underlying ecological processes is secured.

We examined the species richness patterns of five different species groups (mosses, reptiles and amphibians, grasshoppers and crickets, dragonflies, and hoverflies) in the Netherlands (41,500 km 2 ) using sampling units of 5 9 5 km. We compared the spatial patterns of species richness of the five groups using Spearman's rank correlation and used a stepwise multiple regression generalized linear modelling (GLM) approach to assess their relation with a set of 36 environmental variables, selected because they can be related to the several hypotheses on biodiversity patterns. Species richness patterns of the five groups were to a certain extent congruent. Our data suggest that environmental heterogeneity (in particular habitat heterogeneity) is one of the major determinants of variation in species richness within these five groups. We found that for taxonomic groups comprising a low number of species, our regression model explained more of the variability in species richness than for taxonomic groups with a large number of species.

The cicadas (Hemiptera: Cicadidae) related to tribe Cicadini exhibit some of the most remarkable phenotypes in the family, with many genera possessing striking colour patterns and unusual morphological features. This largely Asian group of 13 tribes has proven challenging for cicada taxonomists, in part because of likely convergent evolution or losses of these phenotypes. We present the first focused molecular phylogeny of this clade, including ~60 described genera. The genetic dataset contains 839 ingroup-informative sites (out of 2575) from mitochondrial cytochromec oxidase subunitI, nuclear elongation factor-1α, and nuclear acetyltransferase. We use Bayesian and maximum likelihood trees to test recent changes in tribe- and subtribe-level classification, and we reconstruct ancestral character states for potentially convergent traits influencing tribe descriptions. We use fossil and molecular clock calibrations to estimate the temporal and geographic context of the radiation. The tribes Gaeanini, Leptopsaltriini, Platypleurini, Psithyristriini, and Tosenini appear polyphyletic and in need of revision, in part because of convergent evolution of opaque wings and multiple convergent gains or losses of abdominal tubercles. Kalabita Moulton, 1923 is transferred from Platypleurini to Leptopsaltriini. Vittagaeana gen. nov. is established for Vittagaeana paviei comb. nov. and Vittagaeana dives comb. nov., formerly in Tosena. Sinosenini syn. nov. is synonymised with Dundubiina. Ayuthiini trib. nov. is established with two new subtribes for Ayuthia Distant, 1919 and Distantalna Boulard, 2009, formerly in Tosenini. For the earliest split in the tree, one common ancestor appears to have been Indian + Asian in geographic distribution and the other Asian. We estimate that the radiation began in the middle Cenozoic Era, possibly as recently as the early Miocene. The recent and steady pattern of diversification suggests that refinement of tribe diagnoses will prove challenging. http://zoobank.org:urn:lsid:zoobank.org:pub:5A6C16F4-5269-453B-BA5C-B29C3394683A

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Biogeographical zonation based on single taxa poses major limitations on planning for nature conservation. This paper identifies biogeographical patterns of multiple taxa in the Netherlands, where no endemics are present at species level, on the basis of characteristic species. We used occurrence data on five species groups in order to identify spatially coherent, ecologically important regions. TWINSPAN was used to cluster grid squares according to similarity in species composition for each taxonomic group. Species that are characteristic of each of the clusters were identified using a preference index, and corresponding clusters among the taxonomic groups were identified with Kappa statistics. Regions containing characteristic species for several taxonomic groups were defined as 'hotspots'. Stepwise discriminant analysis was then used to characterize these hotspots according to differences in environmental conditions. The analysis yielded five regions that are clearly distinct in terms of species composition for individual taxonomic groups. Each region is characterized by a set of unique species that occur in the zonation of at least two of the taxonomic groups. Stepwise discriminant analysis revealed significant environmental differences among these regions. The concept of hotspots as operationalized in this study can make nature conservation planning more efficient. In combination, the hotspots 123Biodivers Conserv (2010) 19:2517-2536 DOI 10.1007 defined here comprise the majority of the species occurring in the Netherlands for the studied groups. Therefore, this regionalization should be taken into account when prioritizing nature conservation efforts.