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The cryptic assassin bug subfamily Physoderinae is characterized by a distinctly uneven species and genus-level diversity across continents, but the lack of a phylogeny has so far precluded investigations into the biogeographic history of the group. Endemic Madagascan Physoderinae (11 of the 15 genera) exhibit broad morphological diversity, but the large (38 spp.) and seemingly uniform genus Physoderes is widely distributed across the Oriental and Australasian regions. The three remaining genera are small or even monotypic and restricted to the Neotropical (Cryptophysoderes, Leptophysoderes) and Afrotropical (Porcelloderes) regions. To investigate relationships among Physoderinae, with emphasis on the monophyly of the Madagascan fauna and the monophyly of Physoderes, we conducted a cladistic analysis based on 57 morphological characters and complete genus-level taxon sampling. We found that the Madagascan fauna is not monophyletic, indicating that the island was colonized more than once, although the great majority of Madagascan taxa are part of a single clade. Overall relationships are recovered as Afrotropical Porcelloderes + [(Neotropical Cryptophysoderes, Leptophysoderes) + (Madagascan, Oriental and Australasian taxa)]. Physoderes is shown to be polyphyletic and 3 new genera, Breviphysoderes gen. nov., Macrophysoderes gen. nov. and Nanophysoderes gen. nov., are erected to accommodate new species and several species previously classified as Physoderes. A taxonomic revision of Physoderes and allied genera is conducted. Diagnoses, updated distribution ranges, habitus and genitalic images, and identification keys are provided. A total of 17 synonymies are given, and 15 new species and 3 new genera are described, focusing on the diversity of Physoderinae in the Oriental and Australasian regions. The new species are Breviphysoderes fulvopicta gen. et sp. nov., B. tenebrosa gen. et sp. nov., Macrophysoderes cirripilosa gen. et sp. nov., M. elongata gen. et sp. nov., M. finisterre gen. et sp. nov., M. grandis gen. et sp. nov., Paraphysoderes popeye sp. nov., Physoderes anamalaiensis sp. nov., P. brevipennis sp. nov., P. minime sp. nov., P. muluensis sp. nov., P. mysorensis sp. nov., P. nigripennis sp. nov., P. ractepilosa sp. nov. and P. tricolor sp. nov.
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.
This paper analyzes banks' choice between lending to firms individually and sharing lending with other banks, when firms and banks are subject to moral hazard and monitoring is essential. Multiple-bank lending is optimal whenever the benefit of greater diversification in terms of higher monitoring dominates the costs of free-riding and duplication of efforts. The model predicts a greater use of multiple-bank lending when banks are small relative to investment projects, firms are less profitable, and poor financial integration, regulation and inefficient judicial systems increase monitoring costs. These results are consistent with empirical observations concerning small business lending and loan syndication. JEL Klassifikation: D82; G21; G32.
Der vorliegende Beitrag zeigt auf, wie hedonische Preisindizes für Immobilien auf der Basis von Transaktionen berechnet werden können. Der Heterogenität der Immobilien wird dabei durch ein ökonometrisches Modell Rechnung getragen, wobei in dieser Arbeit das Problem der Wahl einer geeigneten Funktionsform durch eine Transformation nach dem Ansatz von Box/Cox (1964) explizit berücksichtigt wird. Die Datenbasis deckt etwa 65% der Transaktionen des Wohnungsmarktes im Zeitraum 1990-1999 ab. Die Korrektur aufgrund unvollständiger Angaben führt zu einem Datensatz von 84 686 Transaktionen. Dieser Datensatz ist ein Vielfaches dessen, was bisher vergleichbaren Studien zugrunde lag und stellt damit eine international einmalige Datengrundlage dar.
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.
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.
This study develops a novel 2-step hedonic approach, which is used to construct a price index for German paintings. This approach enables the researcher to use every single auction record, instead of only those auction records that belong to a sub-sample of selected artists. This results in a substantially larger sample available for research and it lowers the selection bias that is inherent in the traditional hedonic and repeat sales methodologies. Using a unique sample of 61,135 auction records for German artworks created by 5,115 different artists over the period 1985 to 2007, we find that the geometric annual return on German art is just 3.8 percent, with a standard deviation of 17.87 percent. Although our results indicate that art underperforms the market portfolio and is not proportionally rewarded for downside risk, under some circumstances art should be included in an optimal portfolio for diversification purposes.
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.