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Globally, priority areas for biodiversity are relatively well known, yet few detailed plans exist to direct conservation action within them, despite urgent need. Madagascar, like other globally recognized biodiversity hot spots, has complex spatial patterns of endemism that differ among taxonomic groups, creating challenges for the selection of within-country priorities. We show, in an analysis of wide taxonomic and geographic breadth and high spatial resolution, that multitaxonomic rather than single-taxon approaches are critical for identifying areas likely to promote the persistence of most species. Our conservation prioritization, facilitated by newly available techniques, identifies optimal expansion sites for the Madagascar government's current goal of tripling the land area under protection. Our findings further suggest that high-resolution multitaxonomic approaches to prioritization may be necessary to ensure protection for biodiversity in other global hot spots.

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The island of Madagascar harbors a highly endemic vertebrate fauna including a high diversity of lizards of the subfamily "Scincinae," with about 57 species in eight genera. Since limb reduction seems to have been a common phenomenon during the evolution of Malagasy "scincines," diagnosing evolutionary relationships based on morphology has been difficult. Phylogenetic analyses of multiple mitochondrial DNA sequences including the entire ND1, tRNA(LEU), tRNA(ILE), tRNA(GLN) genes, and fragments of the 12S and 16S rRNA and tRNA(MET) genes were conducted to test the monophyly of the largest genus Amphiglossus, and to evaluate the various formal and informal species groupings previously proposed for this species-rich group. A further objective was to determine the phylogenetic placements of the several greatly limb-reduced and limbless Malagasy "scincines" and ascertain whether any of these are derived from within the morphologically plesiomorphic Amphiglossus. As limb reduction in skinks is mostly associated with body elongation via an increase in the number of presacral vertebrae, we evaluate the pattern of evolution of the numbers of presacral vertebrae in the context of our phylogeny. We demonstrate that Amphiglossus as currently diagnosed is non-monophyletic, and the species fall into two major groups. One of these groups is a clade that contains the included species of the subgenus Amphiglossus (Madascincus) among other species and is a member of a larger clade containing Paracontias and Pseudoacontias. In the second group, the nominate subgenus Amphiglossus (Amphiglossus) forms several subclades within a larger clade that also contains Androngo crenni and Pygomeles braconnieri, and is sister to Voeltzkowia. All analyses provide strong support for the monophyly of Paracontias and Voeltzkowia. Based on the preferred phylogenetic hypothesis and weighted squared-change parsimony we show that the ancestor of the Malagasy clade was already elongated and had a moderately high number of presacral vertebrae (46-48), which is hypothesized to be the ancestral condition for the whole Malagasy "scincine" clade. We further demonstrate that both multiple increases and reductions of presacral vertebrae evolved in many clades of Malagasy "scincines" and that the use of presacral vertebrae as a major character to diagnose supraspecific units is dubious. Based on our results and published morphological evidence we consider Scelotes waterloti Angel, 1930 to be a junior synonym of Amphiglossus reticulatus (Kaudern, 1922).

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Historical biogeography is dominated by vicariance methods that search for a congruent pattern of fragmentation of ancestral distributions produced by shared Earth history. A focus of vicariant studies has been austral area relationships and the break-up of the supercontinent Gondwana. Chameleons are one of the few extant terrestrial vertebrates thought to have biogeographic patterns that are congruent with the Gondwanan break-up of Madagascar and Africa. Here we show, using molecular and morphological evidence for 52 chameleon taxa, support for a phylogeny and area cladogram that does not fit a simple vicariant history. Oceanic dispersal--not Gondwanan break-up--facilitated species radiation, and the most parsimonious biogeographic hypothesis supports a Madagascan origin for chameleons, with multiple 'out-of-Madagascar' dispersal events to Africa, the Seychelles, the Comoros archipelago, and possibly Reunion Island. Although dispersal is evident in other Indian Ocean terrestrial animal groups, our study finds substantial out-of-Madagascar species radiation, and further highlights the importance of oceanic dispersal as a potential precursor for speciation.

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Specimens of the endemic New Zealand frog Leiopelma hochstetteri from Tapu on North Island were found to have six, nine or ten supernumerary chromosomes in their karyotypes. In comparison with previously published data, these results further indicate probable geographic variation in supernumerary chromosome number between populations. Increased numbers of supernumeraries in these frogs is correlated with apparent decrease of centromeric heterochromatin in the five large metacentric chromosomes of the karyotype, as detected by C-banding. Meiosis was abnormal in a male with a high number of supernumeraries. In lampbrush preparations from a single female with one supernumerary univalent, the supernumerary often had a denser, beaded appearance in comparison with the regular bivalents. Evidence is consistent with the notion that these supernumerary chromosomes may have arisen from centromeric fragments.

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