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EARTH SCIENCE > BIOLOGICAL CLASSIFICATION > ANIMALS/INVERTEBRATES > ARTHROPODS

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  • Metadata record for data from AAS (ASAC) project 3010. Public Pycnogonids are primitive, bizarre arthropods. Found worldwide, Antarctic pycnogonids are the most diverse, abundant, and include some of the most spectacular forms. Near 250 species from the region are known, many in need for taxonomic revision, and more species new to science likely to be found. This project will document diversity of pycnogonids and target widely distributed species to obtain morphological, genetic and ecological information on distribution patterns and evolutionary history. This combined approach should provide a better insight of the roles of sea spiders in Antarctic biodiversity and the evolution and radiation of Antarctic marine benthic fauna. Project objectives: 1. To document the diversity of Australian Antarctic pycnogonids at species level and to target species with potential to investigate ecological interactions, zoogeographical patterns and genetic variability. 2. To examine connectivity patterns and genetic differentiation in populations of target species of pycnogonids across large spatial scales inferring diversification processes and possibly speciation rates. 3. To investigate the distribution patterns and possible mechanisms of dispersal of species with apparent wide distributions (e.g. circumpolar distribution, Antarctic -Pacific distribution and Antarctic-Arctic), based on molecular tools. 4. To explore how sea spiders fit evolutionary models testing the origin of deep sea fauna and proposing hypothesis for colonisation mechanisms and radiation processes, as many pycnogonid taxa from the deep sea are also represented on the continental shelf. 5. To resolve phylogenetic questions regarding the affinities among Antarctic species and lower latitude species to understand the evolutionary history of a highly diverse and cosmopolitan lineage (Callipallenidae-Nymphonidae). Details from previous years are available for download from the provided URL. Taken from the 2009-2010 Progress Report: Objective 1 - During this second year of the project more than 500 lots of unsorted samples of pycnogonids are being sorted and identified, many to species level. -In July 2009, 130 lots from the Ross Sea and Subantarctic areas deposited at NIWA in NZ, were sorted, identified and many of them barcoded. Some material has been requested on loan to continue taxonomic studies probably leading to description of new species. -In November 2009, more than 330 lots of CEAMARC samples of sea spiders were received on loan from the Natural History Museum in Paris, where they were deposited in 2008. This material is extremely relevant not only for its diversity but also numbers of individuals per sample. CEAMARC samples (including additional 136 samples from AAD) have provided a unique opportunity to obtain appropriate numbers of individuals of target species such Nymphon australe, with more than 1000 individuals collected. This material is currently being used in analyses about genetic differentiation and diversity at different spatial scales. -Current work in progress on the species level identification of the CEAMARC material would lead to a proper characterisation of the pycnogonid fauna from an extremely important area of the Australian Antarctic territory. We have identified Nymphon australe, Colossendeis megalonyx, Nymphon spp., Austropallene spp. and Pallenopsis spp, as the most frequent and abundant Australian Antarctic pycnogonids and it is expected to correlate abundance and occurrence patterns to other biotic and abiotic parameters that could explain the numbers and diversity of these taxa in the area. - I co-authored a pioneering paper with H. Griffiths (senior author) from BAS and others, on the diversity and biogeography of Antarctic pycnogonids, which was submitted last month to journal Ecography. - At least two new species to science are to be described based on CEAMARC material currently studied. Objective 2 -There is a publication in press (Arango et al.) in the journal Deep-Sea Research II presenting a genetic analysis of the most abundant Antarctic sea spider species Nymphon australe. The study includes 131 individuals of N. australe collected from Antarctic Peninsula, Weddell Sea and East Antarctica. -Additional material of N. australe from CEAMARC made available by MNHN in Paris is currently being analysed to expand the published study and focus on the possible explanations for such wide distribution of a species with apparent limited dispersal capabilities. - Just recently, I established research collaboration with Dr. F. Leese at Ruhr University Bochum, Germany, who is currently interested in the population genetics and genetic connectivity of Antarctic sea spiders. This collaborative effort should prove to be very successful in terms of geographic cover of samples, molecular markers used and analyses implemented. Objective 3 -The paper in press mentioned above addresses the question of circumpolarity of N. australe and finds it might be one of the few 'true' circumpolar species given that the dataset does not reflect cryptic speciation. Preliminary data for other species are showing contrasting results and might reflect 'unknown' species considered cryptic or perhaps just reflects necessity of fine detail taxonomy--. This work on Colossendeis megalonyx is partly in collaboration with Leese's team in Germany. -Material from New Zealand, Tasmania and NSW are currently used for analysis on phylogenetic affinities between Antarctic and non-Antarctic taxa, and also to compare patterns of genetic differentiation among different habitats and taxa. Achelia species distributed from Antarctica to tropical areas will be looked at in a future project depending on funding. Objective 4 -Objective 4 part of a proposal submitted to Australian Biological Resources Study (ABRS) to study deep phylogeny and divergence times of Pycnogonida to understand evolutionary links between Antarctic, deep-sea and Australian shallow waters species, in collaboration with J. Strugnell. During the first and second year of the project advances have been made in terms of literature review, discussion with specialists and most importantly acquisition of material for molecular work that will complement the dataset published in 2007 (Arango and Wheeler 2007). Objective 5 - Since September 2009 I have been actively working on constructing datasets for phylogenetic analyses of Nymphon, the most diverse and abundant taxon of sea spiders in the world, and their closest relatives, the callipallenids, with centre of diversity in Australasia. I am working on including morphological and molecular characters for as many representative species as possible. So far, 30 species are included, and at least 50 morphological are being scored. More species are desired, so I am permanently seeking donation of material, collaborations, etc. the genes COI and 16S are sequenced for at least 50% of the samples included so far, I am currently investigating other molecular markers that might be suitable to resolve a phylogeny at this level. - Given the availability of material from many different species of Colossendeidae, and the relevance and impact of this group --being the family of the giant sea spiders, I am currently collecting material (i.e. tissue samples, DNA sequences, morphological descriptions) to work on the phylogeny of this cosmopolitan family with more than 40 species in the Southern Ocean. At least 15 species have been sequenced so far. The same techniques and methodology as for the Nymphon phylogeny are being applied.

  • Heard Island Bibliography compiled by Evlyn Barrett, (now deceased), contains 573 records. The bibliography has not been updated since 2002, and should not be considered a complete record of publications related to Heard Island.

  • A bibliography of references relating to the outcomes of the RiSCC project (Regional Sensitivity to Climate Change in Antarctic Terrestrial Ecosystems) from the Antarctic and subantarctic regions, dating from 1994 to 2006. The bibliography was compiled by Dana Bergstrom, and contains 162 references.

  • A bibliography of references relating to the research support of the RiSCC project (Regional Sensitivity to Climate Change in Antarctic Terrestrial Ecosystems) from the Antarctic and subantarctic regions, dating from 1875 to 2004. The bibliography was compiled by Dana Bergstrom, and contains 76 references.

  • Metadata record for data from ASAC Project 1229 See the link below for public details on this project. ---- Public Summary from Project ---- This project will develop a method to monitor human impacts in the shallow marine environment of Antarctica. Artificial substratum units, placed at polluted and unpolluted sites, will be recovered after a specific time interval and resident animal communities will be compared to identify the type and magnitude of impacts. Data are community abundance data from artificial substrate units comprised of three nylon mesh pot scourers. Taxa are identified to morphospecies. Substrates were deployed in nearshore waters of Casey Station. Standard deployment was 1 year at 14m depth. Four main sites were used - Brown Bay, Newcombe Bay, O'Brien Bay and Browning Peninsula. Brown Bay is a known contaminated site. Experiments were designed to investigate natural variation on spatial and temporal scales, habitat area and potential impacts of a contaminated site, Brown Bay.

  • Infaunal marine invertebrates were collected from inside and outside of patches of white bacterial mats from several sites in the Windmill Islands, Antarctica, around Casey station during the 2006-07 summer. Samples were collected from McGrady Cove inner and outer, the tide gauge near the Casey wharf, Stevenson's Cove and Brown Bay inner. Sediment cores of 10cm depth and 5cm diameter were collected by divers using a PVC corer from inside (4 cores) and outside (4 cores) each bacterial patch. The size of each patch varied from site to site. Cores were sieved at 500 microns and the extracted fauna preserved in 4 percent neutral buffered formalin. All fauna were counted and identified to species where possible or assigned to morphospecies based on previous infaunal sampling around Casey. An excel spreadsheet is available for download at the URL given below. The spreadsheet does not represent the complete dataset, and is only the bacterial mat infauna data. Regarding the infauna dataset: - in - in the mat or patch of bacteria and out is in the "normal" sediment surrounding the patch without evidence of any bacterial mat presence. - Patch numbers were allocated to ensure there was no confusion between patches in the same area. - Fauna names are our identification codes for each species. Some we have confirmed identifications for, some not. Species names, where we have them and as we get them, are listed against these codes in the Casey marine soft-sediment fauna identification guide. This work was completed as part of ASAC 2201 (ASAC_2201).

  • Our aim was to compare water and sediment as sources of environmental DNA (eDNA) to better characterise Antarctic benthic communities and further develop practical approaches for DNA-based biodiversity assessment in remote environments. We used a cytochrome c oxidase subunit I (COI) metabarcoding approach to characterise metazoan communities in 26 nearshore sites across 12 locations (including Ellis Fjord, Warriner Channel, Hawker Channel, Abatus Bay, Powell Point, Shirokaya Bay, and Weddell Arm) in the Vestfold Hills (East Antarctica) based on DNA extracted from either sediment cores or filtered seawater. We detected a total of 99 metazoan species from 12 phyla (including nematodes, cnidaria, echinoderms, chordates, arthropods, annelids, rotifers and molluscs) across 26 sites, with similar numbers of species detected in sediment and water eDNA samples. Please cite: Clarke LJ et al. (2021). Environmental DNA metabarcoding for monitoring metazoan biodiversity in Antarctic nearshore ecosystems. PeerJ, DOI: 10.7717/peerj.12458 This work was completed as part of the Davis Aerodrome Project (DAP).

  • Sediment Recruitment Experiment 4 (SRE4) was a large, long term (5 year) field experiment run at Casey Station (from 2001 to 2006) testing the effects of 4 different hydrocarbons on marine sediment ecosystems. Four different types of hydrocarbons were individually mixed with defaunated marine sediments and deployed in trays on the seabed at O'Brien Bay-1. Trays were collected after deployment periods of 5 weeks, 56 weeks, 62 weeks, 2 years and 5 years. In addition there was a bioturbation treatment using the burrowing urchin Abatus (at 56 weeks only). Samples were collected from 4 replicate trays of each treatment at each sampling time. Analyses were done of sediment hydrocarbon chemistry, microbial communities, meiofaunal communities, macrofaunal communities and diatom communities. The hydrocarbon treatments were: a synthetic Mobil lubricating oil; the same Mobil lubricating oil after 125? hours use in a vehicle engine; a Fuchs synthetic lubricating oil marketed as highly biodegradable; and Special Antarctic Blend diesel fuel (SAB). A control uncontaminated sediment treatment was used for comparison.

  • Sediment Recruitment Experiment 4 (SRE4) was a large, long term (5 year) field experiment run at Casey Station (from 2001 to 2006) testing the effects of 4 different hydrocarbons on marine sediment ecosystems. Four different types of hydrocarbons were individually mixed with defaunated marine sediments and deployed in trays on the seabed at O'Brien Bay-1. Trays were collected after deployment periods of 5 weeks, 56 weeks, 62 weeks, 2 years and 5 years. In addition there was a bioturbation treatment using the burrowing urchin Abatus (at 56 weeks only). Samples were collected from 4 replicate trays of each treatment at each sampling time. Analyses were done of sediment hydrocarbon chemistry, microbial communities, meiofaunal communities, macrofaunal communities and diatom communities. The hydrocarbon treatments were: a synthetic Mobil lubricating oil; the same Mobil lubricating oil after 125? hours use in a vehicle engine; a Fuchs synthetic lubricating oil marketed as highly biodegradable; and Special Antarctic Blend diesel fuel (SAB). A control uncontaminated sediment treatment was used for comparison.

  • Sediment Recruitment Experiment 4 (SRE4) was a large, long term (5 year) field experiment run at Casey Station (from 2001 to 2006) testing the effects of 4 different hydrocarbons on marine sediment ecosystems. Four different types of hydrocarbons were individually mixed with defaunated marine sediments and deployed in trays on the seabed at O'Brien Bay-1. Trays were collected after deployment periods of 5 weeks, 56 weeks, 62 weeks, 2 years and 5 years. In addition there was a bioturbation treatment using the burrowing urchin Abatus (at 56 weeks only). Samples were collected from 4 replicate trays of each treatment at each sampling time. Analyses were done of sediment hydrocarbon chemistry, microbial communities, meiofaunal communities, macrofaunal communities and diatom communities. The hydrocarbon treatments were: a synthetic Mobil lubricating oil; the same Mobil lubricating oil after 125? hours use in a vehicle engine; a Fuchs synthetic lubricating oil marketed as highly biodegradable; and Special Antarctic Blend diesel fuel (SAB). A control uncontaminated sediment treatment was used for comparison.