Dixon R.R.M.,Murdoch University |
Mattio L.,University of Cape Town |
Mattio L.,Labex Corail Institute Of Recherche Pour Le Developpement |
Huisman J.M.,Murdoch University |
And 6 more authors.
Phycologia | Year: 2014
The Sargassum subgenera Bactrophycus and Arthrophycus were considered to be geographically restricted to the northern and southern hemispheres, respectively. Phylogenetic analyses of 19 Sargassum subgenus Bactrophycus species and eight Sargassum subgenus Arthrophycus species, based on a concatenated dataset of the loci ITS-2, cox3 and the rbcL-S spacer, showed that they formed a single clade, with Arthrophycus species nested within Bactrophycus section Halochloa.We merged the two subgenera as subgenus Bactrophycus and transferred ''Arthrophycus'' species to Sargassum section Halochloa. The genus now includes only the two subgenera, Sargassum and Bactrophycus, and both were found at temperate and subtropical latitudes; only subgenus Sargassum occurred at low latitudes near the equator, whereas subgenus Bactrophycus had an antitropical, disjunct distribution. © 2014 International Phycological Society.
Dixon R.R.M.,Murdoch University |
Huisman J.M.,Bentley Delivery Center |
Buchanan J.,Victoria University of Wellington |
Gurgel C.F.D.,University of Adelaide |
And 3 more authors.
Journal of Phycology | Year: 2012
Sargassum subgenus Phyllotricha currently includes seven species restricted to Australian and New Zealand coasts. A recent study of Cystoseira and other Sargassaceae genera based on mitochondrial 23S DNA and chloroplast-encoded psbA sequences resulted in the most widely distributed species of subgenus Phyllotricha, Sargassum decurrens, being transferred to the reinstated monospecific Sargassopsis Trevisan. The fate of the residual six Phyllotricha species, however, was not considered. The present study examines these Phyllotricha species, alongside other Sargassum subgenera, Sargassopsis, Sirophysalis trinodis (formerly Cystoseira trinodis) and the New Zealand endemic Carpophyllum Greville, using morphological evidence and the molecular phylogenetic markers cox3, ITS-2 and the rbcL-S spacer. Our results suggest both the genus Sargassum and Sargassum subgenus Phyllotricha are polyphyletic as currently circumscribed. Four S. subgen. Phyllotricha species, i.e. S. sonderi, S. decipiens, S. varians and S. verruculosum, form a monophyletic group sister to the genus Carpophyllum, and S. peronii is genetically identical to S. decurrens with regard to all three loci. We propose the resurrection of the genus Phyllotricha Areschoug, with type species Phyllotricha sonderi, and include the new combinations Phyllotricha decipiens, Phyllotricha varians and Phyllotricha verruculosum. Sargassum peronii, S. heteromorphum and S. kendrickii are transferred to Sargassopsis and Sargassum peronii is considered a synonym of Sargassopsis decurrens. © 2012 Phycological Society of America.
Poczai P.,University of Pannonia |
Cseh A.,Hungarian Academy of Sciences |
Taller J.,University of Pannonia |
Symon D.E.,Plant Biodiversity Center
Plant Systematics and Evolution | Year: 2011
The subgenus Archaesolanum is a group composed of eight species with a characteristic chromosome number based on n = x = 23 and an area restricted to the South Pacific. This subgenus is an isolated group of Solanum for which extensive information about phylogenetic relationships based on molecular genetic methods is lacking. This study represents an approach to analyze genetic relationships within this group. In this context, seven species were examined using random amplified polymorphic DNA (RAPD) markers. In further analysis, the amplification products of two chloroplast regions (trnS-trnG and rbcL) were studied with polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) method. Screening for the presence of unique mitochondrial rearrangements was also carried out using universal mitochondrial primers for the detection of fragment length polymorphisms. We identified two major groups within the subgenus; one was composed of the members of ser. Avicularia and Laciniata, while the other was formed by species belonging to ser. Similia. It is suggested that the taxonomic status of series within the Archaesolanum clade should be revised. The hybrid origin of S. laciniatum was also tested, and two hypotheses regarding its phylogeny are assumed. © 2010 Springer-Verlag.
Blair D.,James Cook University |
Mcmahon A.,James Cook University |
Mcdonald B.,James Cook University |
Mcdonald B.,Queensland University of Technology |
And 4 more authors.
Marine Mammal Science | Year: 2014
We investigated phylogeography, demography, and population connectivity of the dugong (Dugong dugon) in Australian waters using mitochondrial control region DNA sequences from 177 Australian dugongs and 11 from elsewhere. The dugong is widespread in shallow Indo-West Pacific waters suitable for growth of its main food, seagrass. We hypothesized that the loss of habitat and creation of a land barrier (the Torres Strait landbridge) during low sea level stands associated with Pleistocene glacial cycles have left a persisting genetic signature in the dugong. The landbridge was most recently flooded about 7,000 yr ago. Individual dugongs are capable of traveling long distances, suggesting an alternative hypothesis that there might now be little genetic differentiation across the dugong's Australian range. We demonstrated that Australian dugongs fall into two distinct maternal lineages and exhibit a phylogeographic pattern reflecting Pleistocene sea-level fluctuations. Within each lineage, genetic structure exists, albeit at large spatial scales. We suggest that these lineages diverged following the last emergence of the Torres Strait landbridge (ca. 115 kya) and remained geographically separated until after 7 kya when passage through Torres Strait again became possible for marine animals. Evidence for population growth in the widespread lineage, especially after the last glacial maximum, was detected. © 2013 by the Society for Marine Mammalogy.
Mckenzie J.,La Trobe University |
Page B.,La Trobe University |
Page B.,Plant Biodiversity Center |
Goldsworthy S.D.,La Trobe University |
And 2 more authors.
Marine Mammal Science | Year: 2013
Abstract : We evaluated the behavioral response of 125 free-ranging New Zealand fur seals (75 females and 50 males) to darting and the effectiveness and safety of midazolam and tiletamine-zolazepam for remote chemical immobilization. Behavioral reactions to darting were minor and brief. Overall, severe reactions to darting such as long flight responses (7%) and escape to the sea (7%) were uncommon. Midazolam administered by dart failed to produce a satisfactory level of immobilization. Tiletamine-zolazepam was administered to 120 animals (35 females and 85 males), 104 of which were successfully immobilized and 16 escaped to the water following darting or attempted net capture. At least 10 of the 16 animals are known to have survived. Tiletamine-zolazepam caused moderate depression of swimming and diving behavior in the animals that escaped to the water. Data from dive loggers confirmed that seals that escaped remained near the sea surface for extended periods. Tiletamine-zolazepam administered by dart at a mean dosage of 1.87 ± 0.18 mg/kg for females and 1.49 ± 0.23 mg/kg for males provided effective and safe immobilization, reducing capture stress for both animals and personnel. Although there is still a risk of drugged animals escaping to the water and possibly drowning, this risk is much lower than previously reported for other pinnipeds. © 2012 by the Society for Marine Mammalogy.
Poczai P.,University of Helsinki |
Hyvonen J.,University of Helsinki |
Symon D.E.,Plant Biodiversity Center
Molecular Biology Reports | Year: 2011
Kangaroo apples, subgenus Archaesolanum, are a unique and still poorly known group within the genus Solanum. Here we aimed to reveal phylogeny, historical biogeography and age of diversification of Archaesolanum. We sampled all recognized species of the group and sequenced three chloroplast regions, the trnT-trnL spacer, trnL intron and trnL-trnF spacer to calibrate a molecular clock to estimate the age of the group. Distributional data were combined with the results of phylogenetic analysis to track the historical processes responsible for the current range of the group. Our analysis supported the monophyly of the kangaroo apples and the biogeographical disjunction between the two subclades within the group. Based on the divergence time estimates the most recent common ancestor of kangaroo apples is from the late Miocene age (∼9 MYA). Based on the age estimate the common ancestors of the kangaroo apples are presumed to have arrived in Australia by long-distance dispersal. The two distinct lineages within the group have separated during the aridification of the continent and further speciated in the brief resurgence of rainforests during the Pliocene. © 2011 Springer Science+Business Media B.V.
Baylis A.M.M.,Deakin University |
Page B.,South Australian Research And Development Institute |
Page B.,Plant Biodiversity Center |
Staniland I.,British Antarctic Survey |
And 2 more authors.
Marine Mammal Science | Year: 2015
The need to manage otariid populations has necessitated the development of a wide range of capture methods. Chemical restraint by remote drug delivery (i.e., darting) is a highly selective method that can be used to facilitate otariid capture in a range of scenarios, when other methods may be impracticable. However, the risks associated with darting otariids are not widely known and guidelines necessary to promote and refine best practice do not exist. We review the risks associated with darting and in light of our findings, develop darting guidelines to help practitioners assess and minimize risks during capture, anesthesia and recovery. Published studies reveal that mortalities associated with darting predominantly result from complications during anesthetic maintenance (e.g., prolonged respiratory depression, apnea, or hyperthermia), rather than from complications during capture or recovery. In addition to monitoring vital signs and proper intervention, the risk of irreversible complications during anesthesia can be reduced by administering drug doses that are sufficient to enable the capture and masking of animals, after which anesthetic depth can be regulated using gas anesthesia. © 2014 Society for Marine Mammalogy.
Chinnock R.J.,Plant Biodiversity Center |
Stajsic V.,National Herbarium of Victoria |
Brodie C.J.,Plant Biodiversity Center
Plant Protection Quarterly | Year: 2012
A newly discovered alien species of Mesembryanthemum, M. guerichianum Pax, is reported for Australia for the first time. It occurs in South Australia, New South Wales and Victoria. It has been overlooked in the past presumably having been mistaken for the widespread M. crystallinum L. which it is closely related to. A detailed account of the species based on Australian populations is given including a description, distribution, ecology, and a brief discussion is provided on current views on the generic limits of Mesembryanthemum. A key to the species of Mesembryanthemum in Australia is provided, and the species is compared with M. crystallinum. © Polymeria Publishing.
Nayar S.,South Australian Research And Development Institute |
Collings G.J.,South Australian Research And Development Institute |
Miller D.J.,Coast and Marine Conservation Branch |
Bryars S.,Plant Biodiversity Center |
Cheshire A.C.,Science to Manage Uncertainty Pty Ltd.
Marine Pollution Bulletin | Year: 2010
Ecologically relevant estimates of seasonal variability in nitrogen uptake and allocation in two species of temperate seagrasses were obtained using in situ isotope-labelling approach. Significantly higher uptake rates of ammonium by leaves, roots and epiphytes of Amphibolis than Posidonia were observed. Overall, root uptake rates were lower than other components. Effect of season was not significant for leaves, roots or epiphytes of the two species. However, plankton uptake varied seasonally with higher rates in winter (0.98mgNg-1DWh-1). In contrast, nitrate uptake rates for various components were significantly affected by seasons. Uptake rates by plankton were highest ranging from 0.003mgNg-1DWh-1 (summer, Amphibolis) to 0.69mgNg-1DWh-1 (winter, Posidonia). Uptake of nitrate by roots was negligible. Biotic uptake rates for nitrate were an order of magnitude slower than ammonium, demonstrating an affinity for ammonium over nitrate as a preferred inorganic nitrogen source. Adelaide coastal waters have lost over 5000ha of seagrasses, much of this attributed to nutrient inputs from wastewater, industrial and stormwater. Managing these inputs into future requires better understanding of the fate of nutrients, particularly biological uptake. This study attempts to quantify uptake rates of nitrogen by seagrasses. © 2010 Elsevier Ltd.
Odgers N.P.,University of Sydney |
Holmes K.W.,Baron Hay Court |
Holmes K.W.,University of Western Australia |
Holmes K.W.,CSIRO |
And 2 more authors.
Soil Research | Year: 2015
It is increasingly necessary to apply quantitative techniques to legacy soil polygon maps given that legacy soil maps may be the only source of soil information over large areas. Spatial disaggregation provides a means of extracting information from legacy soil maps and enables us to downscale the original information to produce new soil class maps at finer levels of detail. This is a useful outcome in its own right; however, the disaggregated soil-class coverage can also be used to make digital maps of soil properties with associated estimates of uncertainty. In this work, we take the spatially disaggregated soil-class coverage for all of Western Australia and the agricultural region of South Australia and demonstrate its application in mapping clay content at six depth intervals in the soil profile. Estimates of uncertainty are provided in the form of the 90% prediction interval. The work can be considered an example of harmonisation to a common output specification. The validation results highlighted areas in the landscape and taxonomic spaces where more knowledge of soil properties is necessary. © CSIRO 2015.