25 research outputs found

    Palaeontology, the biogeohistory of Victoria

    Full text link
    The broad-scale distribution of fossils within Victoria is controlled by general global patterns in the biological evolution of life on Earth, the local development and environmental evolution of habitats, and the occurrence of geological processes conducive to the preservation of fossil floras and faunas. Early Palaeozoic fossils are mostly marine in origin because of the predominance of marine sedimentary rocks in Victoria and because life on land was not significant during most of this time interval. Middle Palaeozoic sequences have both terrestrial and marine fossil records. Within Victoria, marine rocks are only very minor components of strata deposited during the late Palaeozoic, so that few marine fossils are known from this time period. A similar situation existed during most of the Mesozoic except towards the end of this era when marine conditions began to prevail in the Bass Strait region. During long intervals in the Cainozoic, large areas of Victoria were flooded by shallow-marine seas, particularly in the southern basins of Bass Strait, as well as in the northwest of the State (Murray Basin). Cainozoic sediments contain an extraordinary range of animal and plant fossils. During the Quaternary, the landscape of Victoria became, and continues to be, dominated by continental environments including, at times, extensive freshwater lake systems. Fossil floras and faunas from sediments deposited in these lake systems and from other continental sediments, as well as from Quaternary sediments deposited in marginal marine environments, collectively record a history of rapid fluctuations in climate and sea level.<br /

    Late Silurian and Early Devonian biostratigraphy in the Hill End Trough and the Limekilms area, New South Wales

    No full text
    The first recorded graptolites from the Cheslcigh Formation of the Limekilns district are Monograptus prognatus, ?M. transgrediens, Pristiograptus sp. cf. P. shearsbyi and Linograptus posthumus, which unequivocally indicate a Prldolt (Late Silurian) age for the formation. The Silurian-Devonian boundary appears best placed at approximately the boundary between the Chesleigh Formation and the overlying Cookman Formation, despite the presence of the early Lochkovian graptolite Monograptus uniformis uniformis much higher stratigraphically in the Limekilns Formation. In the Hill End Trough succession, the Turondale Formation has yielded conodonts including Amydrotaxis praejohnsoni, which indicates the delta to pesavis conodont Zones of late Lochkovian (Early Devonian) age. Conodonts from the upper p ayt of the Cunningham Formation, at a locality in the Trough west of Mudgee, include Polygnathus nothoperbonus /P. inversus, indicating theperbonus zone of middle Emsian age. The base of the Cunningham Formation is diachronous, being late Lochkovian (delta Zone) - the same age as the Turondale Formation - on the west flank of the Trough as previously reported, and late Pragian in the east. The youngest faunas found in the unit are late Emsian

    Oldest coelacanth, from the Early Devonian of Australia

    No full text
    Coelacanths are well-known sarcopterygian (lobe-finned) fishes, which together with lungfishes are the closest extant relatives of land vertebrates (tetrapods). Coelacanths have both living representatives and a rich fossil record, but lack fossils older than the late Middle Devonian (385–390 Myr ago), conflicting with current phylogenies implying coelacanths diverged from other sarcopterygians in the earliest Devonian (410–415 Myr ago). Here, we report the discovery of a new coelacanth from the Early Devonian of Australia (407–409 Myr ago), which fills in the approximately 20 Myr ‘ghost range’ between previous coelacanth records and the predicted origin of the group. This taxon is based on a single lower jaw bone, the dentary, which is deep and short in form and possesses a dentary sensory pore, otherwise seen in Carboniferous and younger taxa

    Skrjabinodon heliocostai sp.n. (Nematoda, Pharyngodonidae) parasitizing Mabuya frenata (Cope) (Lacertilia, Scincidae) in Brazil and the reallocation of Skrjabinodon capacyupanquii (Freitas, Vicente & Ibanez) in the genus Thelandros Wedl

    No full text
    The present report is related to an oxyurid nematode recovered from a reptilian host, Mabuya frenata (Cope, 1862) and the proposal of Skrjabinodon helicostai sp.n., based mainly on findings referring to the lateral alae, position of excretory pore and vulvar apertures, cuticular spines of the tail and aspect of the eggs. The examination of types of Skrjabinodon capacyupanquii (Freitas, Vicente & Ibanez, 1968) from a Peruvian lizard, indicated the reallocation of this species in the genus Thelandros Wedl., 1862, as T. capacyupanquii comb.n., based on the diameter of the caudal appendage of males and position of the vulvar aperture. The new species described herein represents the first report of a species of the genus Skrjabinodon Inglis, 1968 in South America

    Production of L(+) lactic acid using Lactobacillus casei from whey

    No full text
    The aim of this work was to study the fermentation of whey for the production of L(+) lactic acid using Lactobacillus casei. The effect of different process parameters such as pH of the medium, temperature, inoculum size, age of inoculum, agitation and incubation time was monitored to enhance the lactose conversion in whey to L(+) lactic acid. Fermentations were performed without any pH control. The optimization of the fermentation conditions resulted in significant decrease in fermentation time, besides increase in lactose conversion to lactic acid. The optimized process conditions resulted in high lactose conversion (95.62%) to L(+) lactic acid production (33.73 g/L) after an incubation period of 36 h

    Devonian operculate corals (Calceolidae, Cnidaria) from the Massif Armoricain, France

    No full text
    The operculate coral Calceola gervillei Bayle, 1878 is described for the first time on the basis of the type material from the Cotentin region of Normandy (North Armorican Domain), from Early Devonian (likely upper Lochkovian to lower Pragian) strata, and is chosen as the type species of the monotypic new genus Gerviphyllum. The new genus is also present in the l\u27Armorique Formation (lower Pragian) of the Plougastel Peninsula (Central Armorican Domain) as Gerviphyllum sp. cf. G. gervillei. One locality in the upper Emsian (Polygnathus serotinus Conodont Zone) Le Fret Formation, on the northern coast of the Crozon Peninsula, has yielded operculate coral specimens described here as ?Chakeola sp., the first (tentative) record of the genus outside eastern Australia, south China and Vietnam. The operculate coral Calceola collini sp. nov. is described from six localities in the early Middle Devonian (Eifelian: Polygnathus costatus Conodont Zone) Saint-Fiacre Formation of the Plougastel and Crozon Peninsulas (Central Armorican Domain), despite the fact that knowledge of the internal characters, especially of the operculum, of the type species Calceola sandalina is very limited. From an extensive review of published references to Calceola from France, we conclude that only the record of Collin (1929) is valid
    corecore