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CURATOR

PhD student, University of Queensland

PINBOARD SUMMARY

Identify and describe new species of Australian tarantulas, focusing on conservation and management.

Australian Tarantulas are being revised and at least 17 new species and 2 new genera are being described. Four genera, Phlogius, Selenotholus, Selenotypus and Coremiocnemis, and currently 7 species are known. Massive confusion exists in the pet trade about names which the revision will address. However, an impasse has been reached about the species and even genus boundaries, neither diverse qualitative characters (hair length and density) nor statistically sampled quantitative characters (leg thickness and length) have been completely useful. Raven (2005) briefly reviewed the status and named one species. We know from breeding experiments that the eastern tarantula, Phlogius crassipes, ranging from Cape York to Rockhampton, may be a cryptic species complex. Morphological and molecular data will test this hypothesis. Clearly defining species boundaries is critical for the conservation management of this threatened group of spiders. The Theraphosidae (tarantulas) include the largest spiders in Australia and they are the next step in the pet market. They are now Listed species and their capture, keep and even movement across state borders is now regulated. These animals lack good morphological characters and species variability is a major problem. Sexual characters are almost invariable across its range. Modern tools, such as DNA, are needed to help to resolve the dilemmas. Sound knowledge of tarantula species is critical to ensure the species' survival. Correct identification of tarantulas is critical to the process of any scientific study on the group; this project will be a major step on that path.

4 ITEMS PINNED

Forest wildlife management and conservation.

Abstract: Forests are critical for the world's biodiversity, the regulation of the Earth's climate, and the provision of goods and services for humans. This review focuses on four broad topics: (1) key processes threatening forest biodiversity; (2) broad strategies for mitigating threatening processes; (3) climate change and forest biodiversity; and, (4) plantations and biodiversity. How key issues within these broad topics are addressed will have profound effects on forest biodiversity and the Earth's climate. A significant global problem for biodiversity conservation is the conversion of natural forests to other land uses, both in developing and developed nations; ways must be urgently identified to halt forest conversion. When forests are logged for timber or pulpwood and then regenerated, impacts on biodiversity are harder to quantify than when forests are converted to other land uses. Hence, the effectiveness of efforts to mitigate such impacts (where they occur) is frequently not well known. Climate change may result in substantial changes to forest ecosystems, and its effects may interact in additive or cumulative ways with other human disturbances in forests, although work on such combinations of impacts is in its infancy. The establishment of plantations of trees is frequently proposed to sequester large amounts of carbon and/or produce biofuels to mitigate the climate-change effects. However, there is potential for perverse outcomes, such as biodiversity loss where plantation establishment is narrowly focused and other environmental values are ignored.

Pub.: 13 May '09, Pinned: 27 Jul '17

How to describe a cryptic species? Practical challenges of molecular taxonomy.

Abstract: Molecular methods of species delineation are rapidly developing and widely considered as fast and efficient means to discover species and face the 'taxonomic impediment' in times of biodiversity crisis. So far, however, this form of DNA taxonomy frequently remains incomplete, lacking the final step of formal species description, thus enhancing rather than reducing impediments in taxonomy. DNA sequence information contributes valuable diagnostic characters and -at least for cryptic species - could even serve as the backbone of a taxonomic description. To this end solutions for a number of practical problems must be found, including a way in which molecular data can be presented to fulfill the formal requirements every description must meet. Multi-gene barcoding and a combined molecular species delineation approach recently revealed a radiation of at least 12 more or less cryptic species in the marine meiofaunal slug genus Pontohedyle (Acochlidia, Heterobranchia). All identified candidate species are well delimited by a consensus across different methods based on mitochondrial and nuclear markers.The detailed microanatomical redescription of Pontohedyle verrucosa provided in the present paper does not reveal reliable characters for diagnosing even the two major clades identified within the genus on molecular data. We thus characterize three previously valid Pontohedyle species based on four genetic markers (mitochondrial cytochrome c oxidase subunit I, 16S rRNA, nuclear 28S and 18S rRNA) and formally describe nine cryptic new species (P. kepii sp. nov., P. joni sp. nov., P. neridae sp. nov., P. liliae sp. nov., P. wiggi sp. nov., P. wenzli sp. nov., P. peteryalli sp. nov., P. martynovi sp. nov., P. yurihookeri sp. nov.) applying molecular taxonomy, based on diagnostic nucleotides in DNA sequences of the four markers. Due to the minute size of the animals, entire specimens were used for extraction, consequently the holotype is a voucher of extracted DNA ('DNA-type'). We used the Character Attribute Organization System (CAOS) to determine diagnostic nucleotides, explore the dependence on input data and data processing, and aim for maximum traceability in our diagnoses for future research. Challenges, pitfalls and necessary considerations for applied DNA taxonomy are critically evaluated.To describe cryptic species traditional lines of evidence in taxonomy need to be modified. DNA sequence information, for example, could even serve as the backbone of a taxonomic description. The present contribution demonstrates that few adaptations are needed to integrate into traditional taxonomy novel diagnoses based on molecular data. The taxonomic community is encouraged to join the discussion and develop a quality standard for molecular taxonomy, ideally in the form of an automated final step in molecular species delineation procedures.

Pub.: 01 Oct '13, Pinned: 27 Jul '17