In 2007 an unusual crayfish found in food markets in the capital of Madagascar was preliminarily identified as Procambarus 'Marmorkrebs': a new world taxa and the only decapod known to reproduce by parthenogenesis. We present information on the identity, distribution and ecology of this recent invader and attempt to evaluate the threat it poses to Madagascar's biodiversity and to livelihoods. The species appears to be currently limited to the area close to Antananarivo, but is being sold alive on major transport routes. We present molecular evidence of its taxonomic relationships and confirm that the Procambarus present in Madagascar is indeed the parthenogenic taxa. We investigate its reproductive ecology and find Procambarus 'Marmorkrebs' to have an extremely high fecundity; more than six times that of the native crayfish Astacoides. The limited evidence we have suggests that this species poses a serious threat to freshwater biodiversity and that it is likely to damage human livelihoods (through its impact on fishing and possibly rice agriculture). More research is urgently needed but in the meantime action is needed to reduce the rate of spread before it is too late.

While many studies have documented the effect that glacial cycles have had on northern hemisphere species, few have attempted to study the associated effect of aridification at low latitudes in the southern hemisphere. We investigated the past effects that cyclic aridification may have had on the population structure and history of a widespread endemic Australian bird species, the Australian magpie (Gymnorhina tibicen). One thousand one hundred and sixty-six samples from across its native range were analysed for mitochondrial control region sequence variation and variation at six microsatellite loci. Analysis of mitochondrial control region sequence data indicated monophyletic clades that were geographically congruent with an eastern and western region. The contemporary distribution of east and west clades is nonoverlapping but in close proximity. Populations were estimated to have diverged in the Pleistocene around 36,000 years ago. The putative Carpentarian and Nullarbor arid barriers appear to be associated with the divergence between east and west mainland populations. Nested clade analysis indicated a signature of range expansion in the eastern region suggesting movement possibly inland and northward subsequent to the last period of aridity. The island population of Tasmania was of very recent origin, possibly since sea levels rose 16,000 years ago. Given the east-west structure, there was no congruence between morphology and recent history of this species indicating a lack of support for morphological taxa. Overall mitochondrial DNA and microsatellite variation suggest that increasing aridity and Pleistocene refugia played a role in structuring populations of the Australian magpie; however, the dispersal ability and generalist habitat requirements may have facilitated the movement of magpies into an almost contiguous modern distribution across the continent. This study supports the idea that Pleistocene aridification played an important role in structuring intraspecific variation in low latitudinal southern hemisphere avian species.

Multilocus studies in phylogenetics and comparative phylogeography have the power to explore a broader spectrum of evolutionary questions than either discipline has alone. To examine the origins of sympatry in a group of closely related birds of mostly mesic eucalypt woodlands in Australia, we reconstructed the relationships among species of Entomyzon and Melithreptus honeyeaters (Aves: Passeriformes: Meliphagidae) using a mitochondrial marker, ND2, and six non-coding nuclear loci (total 4719 base pairs). By sampling across the geographical range of each species, we studied not only their phylogenetic relationships to each other but also the spatial distribution of their genetic diversity. We tested several biogeographic hypotheses concerning the role of Pleistocene environmental change in Australia. Phylogenetic gene trees support the current understanding of E. cyanotis as the sister to Melithreptus. Non-monophyly of M. lunatus in Australia's southern temperate woodlands highlights the need for a revision of systematics within Melithreptus. Phylogeographic analysis of the three northern species in Australia's monsoon tropics, M. gularis, M. albogularis and E. cyanotis, suggests that the roles of the Carpentarian and Torresian Barriers in shaping geographic structure in each of the species have been more complex and temporally dynamic than earlier morphology-based arguments of vicariance had suggested. We discuss their roles as ecological filters as well as barriers.

A model of range expansions during glacial maxima (GM) for cold-adapted species is generally accepted for the Northern Hemisphere. Given that GM in Australia largely resulted in the expansion of arid zones, rather than glaciation, it could be expected that arid-adapted species might have had expanded ranges at GM, as cold-adapted species did in the Northern Hemisphere. For Australian biota, however, it remains paradigmatic that arid-adapted species contracted to refugia at GM. Here we use multilocus data and ecological niche models (ENMs) to test alternative GM models for butcherbirds. ENMs, mtDNA and estimates of nuclear introgression and past population sizes support a model of GM expansion in the arid-tolerant Grey Butcherbird that resulted in secondary contact with its close relative--the savanna-inhabiting Silver-backed Butcherbird--whose contemporary distribution is widely separated. Together, these data reject the universal use of a GM contraction model for Australia's dry woodland and arid biota.

The last 20 years have seen a resurgence in systematic studies of parrots (Aves: Psittaciformes). Principally but not solelymolecular in nature, this body of work has addressed the circumscription of higher level groupings within the Psittaciformesand relationships among them. Stability has now emerged on many formerly contentious matters at these levels. Accordingly,we consider it appropriate to underpin further work on parrot biology with a freshly revised classification at the taxonomicranks spanned by family-group nomenclature, i.e., between superfamily and tribe. In light of the body of recent work, we advo-cate a framework of three superfamilies among parrots (Strigopoidea, Cacatuoidea and Psittacoidea) within which Linnaeantaxonomy can accommodate present phylogenetic understanding by employing groupings at the ranks of family, subfamily andtribe. Just as importantly, we have addressed numerous issues of nomenclature towards stabilising the family-group names ofparrots. We erect two new subfamily names, Coracopseinae Joseph, Toon, Schirtzinger, Wright & Schodde, subfam. nov. andPsittacellinae Joseph, Toon, Schirtzinger, Wright & Schodde, subfam. nov. We stress that rankings we have applied reflect thestate of understanding of parrot phylogeny and how it can be summarized in a Linnaean system; comparisons with rankings in other groups are likely not appropriate nor relevant.