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The erasipterid Sinoerasipteron xiaheyanensis Nel & Huang gen. et sp. nov. from the Moscovian Tupo Formation in Xiaheyan locality (China), is described and illustrated. It is the sixth species of the odonatopteran griffenflies from this locality. This new discovery confirms the high diversity of these flying predators in the insect assemblage.
Crenicichla is the largest and most widely distributed genus of Neotropical cichlids. The Crenicichla mandelburgeri species complex from the Middle Paraná departs from the ancestral and predominant ecomorphology of the large genus and shows parallel evolution of ecomorphs both within the complex and also to the unrelated C. missioneira species complex from the Uruguay River. Here, we formally describe a new species pair from the C. mandelburgeri species complex that has evolved a parallel morphological and ecological dichotomy to another species pair and also to species in the unrelated C. missioneira species complex. The new species pair is endemic to a single tributary (the Piray Guazú) of the Middle Paraná River where it is sympatric and partly syntopic. Mitochondrial DNA phylogeny shows the two new species as distantly related within the C. mandelburgeri species complex, each with a sister species in the Iguazú rather than in the neighbouring Paraná River tributaries. Nuclear DNA analyses demonstrate their sister-group relationship, which is however complicated by the reticulated origin of one of the new species. We present determination keys for all the currently formally described species of the C. mandelburgeri species complex including the new species described here.
The abiotic and biotic drivers of rapid diversification in Andean bellflowers (Campanulaceae)
(2016)
The tropical Andes of South America, the world's richest biodiversity hotspot, are home to many rapid radiations. While geological, climatic, and ecological processes collectively explain such radiations, their relative contributions are seldom examined within a single clade. We explore the contribution of these factors by applying a series of diversification models that incorporate mountain building, climate change, and trait evolution to the first dated phylogeny of Andean bellflowers (Campanulaceae: Lobelioideae). Our framework is novel for its direct incorporation of geological data on Andean uplift into a macroevolutionary model. We show that speciation and extinction are differentially influenced by abiotic factors: speciation rates rose concurrently with Andean elevation, while extinction rates decreased during global cooling. Pollination syndrome and fruit type, both biotic traits known to facilitate mutualisms, played an additional role in driving diversification. These abiotic and biotic factors resulted in one of the fastest radiations reported to date: the centropogonids, whose 550 species arose in the last 5 million yr. Our study represents a significant advance in our understanding of plant evolution in Andean cloud forests. It further highlights the power of combining phylogenetic and Earth science models to explore the interplay of geology, climate, and ecology in generating the world's biodiversity.
In this paper, we calculate a transaction–based price index for apartments in Paris (France). The heterogeneous character of real estate is taken into account using an hedonic model. The functional form is specified using a general Box–Cox function. The data basis covers 84 686 transactions of the housing market in 1990:01–1999:12, which is one of the largest samples ever used in comparable studies. Low correlations of the price index with stock and bond indices (first differences) indicate diversification benefits from the inclusion of real estate in a mixed asset portfolio. JEL C43, C51, O18, R20.