The Upper Cretaceous foraminiferal record of IODP Site U1512 (Great Australian Bight, Indian Ocean)

<p>Site U1512 was drilled during Expedition 369 of the International Ocean Discovery Program (IODP), which is located in the Great Australian Bight, southern Indian Ocean. It provides exceptional insights into the benthic foraminiferal biostratigraphy and paleoecology of a high southern latitude restricted marginal marine basin during the Late Cretaceous hot greenhouse climate and the rifting between Australia and Antarctica. The sedimentary sequence recovered at Site U1512 presents a rare record of a deep water agglutinated foraminifera (DWAF) community from the Southern High Latitudes. The Cretaceous record at Site U1512 covers the lower Turonian through Santonian (nannofossil zones UC8b to UC12/CC10b to CC16, <em>H. helvetica</em> to <em>Marginotruncana</em> spp. - <em>Planoheterohelix papula</em> - <em>Globotruncana linneana</em> planktonic foraminifera zones). Diverse benthic foraminiferal assemblages yield many new taxa that are yet to be described.</p><p>Agglutinated forms dominate the assemblage in most intervals. In lower to mid Turonian and Santonian strata, calcareous benthic as well as planktonic foraminifera are frequent. Abundant radiolaria are recovered from the mid Turonian, and they increase up-section and exceed 50% of the microfossil assemblage. We documented a diverse benthic foraminiferal assemblage consisting of 162 taxa (110 agglutinated and 52 calcareous). The most common taxa of the DWAF assemblage are tubular (i.e., <em>Kalamopsis grzybowskii,</em> <em>Bathysiphon</em> spp.) and planispiral forms (i.e., <em>Ammodiscus</em> spp., <em>Haplophragmoides</em> spp., <em>Buzasina</em> sp., <em>Labrospira</em> spp.).</p><p>The Turonian strata yield highly abundant <em>Bulbobaculites problematicus</em> and <em>Spiroplectammina navarroana</em>. The presence of the agglutinated foraminiferal marker taxa <em>Uvigerinammina jankoi</em> and <em>Bulbobaculites problematicus</em> provides a tie-point to the Tethyan DWAF biozonation of Geroch and Nowak (1984). The composition of foraminiferal assemblages and the increase in radiolaria abundance suggest unstable environmental conditions at Site U1512 during the early Turonian through Santonian. These characteristics refer to changes in bathymetry associated with changing ocean chemistry. Results of quantitative analyses of the benthic foraminiferal assemblages indicate a restricted paleoenvironmental regime, dictated by changes in paleobathymetry, unstable patterns in ocean circulation, and the discharge of a nearby river delta system.</p><p>References: Geroch, S., Nowak, K., 1984. Proposal of zonation for the Late Tithonian – late Eocene. based upon arenaceous Foraminifera from the Outer Carpathians, Poland, 225-239, In: Oertli, H.J. (Ed.), Benthos ´83; 2nd international 915 Symposium on Benthic Foraminifera, Pau (France) April 11-15, 1983, Elf Aquitaine, ESO REP and TOTAL CFP, Pau and Bordeaux.</p><p> </p>

Annelids of the eastern Australian abyss collected by the 2017 RV ‘Investigator’ voyage

In Australia, the deep-water (bathyal and abyssal) benthic invertebrate fauna is poorly known in comparison with that of shallow (subtidal and shelf) habitats. Benthic fauna from the deep eastern Australian margin was sampled systematically for the first time during 2017 RV ‘Investigator’ voyage ‘Sampling the Abyss’. Box core, Brenke sledge, and beam trawl samples were collected at one-degree intervals from Tasmania, 42°S, to southern Queensland, 24°S, from 900 to 4800 m depth. Annelids collected were identified by taxonomic experts on individual families around the world. A complete list of all identified species is presented, accompanied with brief morphological diagnoses, taxonomic remarks, and colour images. A total of more than 6000 annelid specimens consisting of 50 families (47 Polychaeta, one Echiura, two Sipuncula) and 214 species were recovered. Twenty-seven species were given valid names, 45 were assigned the qualifier cf., 87 the qualifier sp., and 55 species were considered new to science. Geographical ranges of 16 morphospecies extended along the eastern Australian margin to the Great Australian Bight, South Australia; however, these ranges need to be confirmed with genetic data. This work providing critical baseline biodiversity data on an important group of benthic invertebrates from a virtually unknown region of the world’s ocean will act as a springboard for future taxonomic and biogeographic studies in the area.

CHARACTERISING COASTAL SHELF WAVES ALONG THE NSW COAST

New South Wales (NSW) often experiences periods of coastal inundation and estuarine flooding. One of the causal mechanisms of these episodes are coastal shelf waves (CSW), generated by synoptic disturbances (Church et al., 2006). CSWs in Australia often result from wind stress, mostly along mid-latitudes (e.g., the Great Australian Bight) and propagate anticlockwise (Woodham et al., 2013). However, there are no tools available for identifying and characterising CSWs and as such there is very little information on the magnitude, frequency, duration, and spatiotemporal variability. This paper aims to: (1) develop a method to identify and track CSWs using the existing ocean tide gauge network, (2) identify patterns in the frequency, duration, and magnitude of CSW, and (3) assess the factors that affect the frequency, duration, and magnitude of CSWs along the NSW coast.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/oigzYIKFBmA

First record of the Deepsea pigfish Congiopodus coriaceus (Scorpaeniformes: Congiopodidae) in the Great Australian Bight with new data on morphology

The Deepsea pigfish Congiopodus coriaceus Paulin et Moreland, 1979 is recorded from the waters off the southern coast of Australia, Great Australian Bight for the first time, based on a juvenile specimen SL 64 mm collected in 1966. This is the westernmost known locality of the species, 3500 km from the type locality off New Zealand. The lack of published data after the original description of the species revealed the need to clarify a number of meristic and morphometric parameters. Based on x-ray images of 28 ZIN specimens of C. coriaceus from New Zealand, the range of individual variability in the number of vertebrae, the number of rays of the dorsal and anal fins is shown. The number of procurrent and principal rays in the caudal fin has been clarified. In some cases, the range of morphometric parameters published in the original description has been expanded, for example, the maximum body height and head length. The original description was supplemented with 16 new measurements. For the first time, data on the lengths of the ventral and caudal fins, the length and height of the caudal peduncle, and the interorbital distance were published. Because of contradictory published data on the number of gill rakers on the first branchial arch, their number was clarified; the diagnostic value of this parameter was confirmed.

New carnivorous sponges and allied species from the Great Australian Bight

This research presents three new species of carnivorous sponges from the family Cladorhizidae from the Great Australian Bight, South Australia. This research also shows a clear separation within the species currently known as Cladorhiza into those with an arbuscular or tree-like morphology from the Atlantic, to those of differing morphologies and propose three new genera, i.e. Bathytentacular gen. nov., Abyssosdiskos gen. nov. and Nullarbora gen. nov. and the resurrection of an old genus Axoniderma. nov. The three new species described in this paper are Nullarbora heptaxia sp. nov., Abyssocladia oxyasters sp. nov. and Lycopodina hystrix sp. nov. A new species in the family Guitarridae, Guitarra davidconryi sp. nov., a family closely related to the carnivorous sponges is also described in this paper. These new species are the first recorded carnivorous species from South Australia and increase the number of species recorded from around Australia to 25.