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A new Australian genus of Orthotylinae, Myrtlemiris Cheng, Mututantri & Cassis gen.n. , is described, with nine included species described as new to science (M. agnew sp.n. , M. astartephila sp.n. , M. meanarra sp.n. , M. newmanensis sp.n. , M. rubrocuneatus sp.n. , M. russulatus sp.n. , M. silveirae sp.n. , M. tesselatus sp.n. , M. yalgoo sp.n. ). A phylogenetic analysis based on 39 morphological characters is presented for all Myrtlemiris species and 6 outgroup taxa. This analysis establishes Myrtlemiris as monophyletic, defined by a broad apophysis on the left paramere. A key to species is provided and diagnostic characters are illustrated. Myrtlemiris is endemic to southwest Western Australia. Host plants for Myrtlemiris species are near restricted to the myrtaceous tribe Chamelaucieae.  相似文献   
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Biodiversity investment priorities are a major concern for funding agencies and parties to the Convention on Biodiversity. We present a cost-effectiveness index designed to rank global biodiversity investments addressing weaknesses identified in several existing procedures. First, we explicitly address the issue of cost. Biodiversity conservation can be expensive -- ensuring that money is efficiently spent is important if conserving maximum biodiversity is an objective. Second, a high degree of threat to biodiversity is commonly accepted as constituting the principal reason for intervention and a basis for prioritization. The possibility that a high degree of threat might constitute a reason for non-intervention is rarely considered. The index presented in this study seeks to address these shortcomings by incorporating biodiversity ‘cost’, as measured by investment, and biodiversity ‘benefit’, as measured by a representative biodiversity indicator, species, richness. These elements form the basis of the cost -- benefit ratio needed for cost-effectiveness analysis. Investment in biodiversity is affected by issues of vulnerability (threat) and viability (success). A successful investment intervention will, however, depend on the probability or likelihood of success and the degree of threat prevalent in a particular country. These are integrated into the index as probabilities which will influence the amount of biodiversity ‘saved’ by an intervention. We apply the index using data for the Asia – Pacific region, to provide a cost-effective priority investment index (CEPII) ranking by country. Acute data limitations at the global level particularly in applying complementarity, necessitate caution in the interpretation of the index which, like other methods, requires some subjective choice of success and threat surrogates. The index continues the task of combining scientific and socioeconomic criteria relevant to global priorities. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
3.
Velasco recently criticized our formal definition of the species concept, arguing for its inappropriateness both in fundamental and practical aspects [Velasco JD (2008) Biological Journal of the Linnean Society , 93 , 865–869]. Here, we clarify some misunderstandings that are at the basis of Velasco's paper. First, we show why and how the definition of the species concept can be grounded in the theory of evolution and what that implies. Then, we explain why Velasco's formal criticisms are unjustified. Finally, we point out the practical and methodological consequences of a rigorous conceptual framework for species study, and we show that today's development of species delimitation methods fully agrees with our proposal.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 217–222.  相似文献   
4.
The tree, the network, and the species   总被引:2,自引:0,他引:2  
To enrich the Hennigian internodal conception of species, a new formalization of the definition of the species concept is proposed. This rigorous definition allows for considerable unification of the various, and sometimes conflicting, techniques of species delimitation used in practice. First, the domain of such a definition is set out, namely, the set of all organisms on Earth, past, present, and future. Next, the focus is on the genealogical relationship among organisms, which provides the key to analysing the giant or global genealogical network (GGN) connecting all these organisms. This leads to the construction of an algorithm revealing the topological structure of the GGN, from families to lineages, ending up with a definition of species as equivalence classes of organisms corresponding to branches of the 'tree of life'. Such a theoretical definition of the species concept must be accompanied by various recognition criteria to be operational. These criteria are, for example, the ill-named 'biological species concepts', 'phylogenetic species concepts', etc., usually, but wrongly, presented as definitions of the species concept. Besides clarifying this disputed point, the definition in the present study displays the huge diversity of the scales (time-scale and population size) involved in actual species, thus explaining away the classical problems raised by previous attempts at defining the species concept (uniparental reproduction, temporal depth of species, and hybridization).  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 509–521.  相似文献   
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