Morphometric analysis of orange roughy (Hoplostethus atlanticus) off the continental slope of southern Australia

Morphometric variation was used to examine the stock structure, in southern Australian waters, of the deepwater marine teleost Hoplostethus atlanticus , orange roughy. Seven samples were collected from non-spawning aggregations in 1989–1990. Three samples were also collected in the winter of 1992, two from the main spawning site off the eastern coast of Tasmania (St Helens), and the third from the other main fishing ground south of Tasmania. The 38 morphometric measurements taken from each of over 1300 fish were size-standardized by an allometric formula and analysed by univariate and multivariate statistics. The results indicate significant variation in the morphology of orange roughy caught from geographically distinct aggregations. They further suggest that the main spawning aggregation may consist of fish from different groups at different times of the spawning period. There appear to be at least seven morphologically distinguishable stocks of orange roughy in southern Australian waters, despite genetic data indicating appreciable levels of gene flow between them.     

Late Quaternary paleoceanography as recorded by benthonic foraminifera in Strait of Sicily sediment sequences

At specific times during the late Quaternary, a widespread low-salinity surface water layer was produced over the eastern Mediterranean which created stagnant conditions and associated deposition of sapropelic muds in the deep basins. The Strait of Sicily has been positioned above the anoxic deeper water masses and is therefore devoid of sapropel deposits. Sediment sequences in the region contain a valuable record of upper bathyal (200–1000 m) benthonic foraminiferal change during times of deep-basin stagnation.Quantitative examiniation of benthonic foraminiferal assemblages in Strait of Sicily Quaternary cores generally reveals changes coeval with sapropels S1, S2, S4, S5, and S6. The benthonic foraminiferal expression is seen as increases in frequency ofGlobobulimina affinis, Globobulimina pseudospinescens, Chilostomella mediterranensis, Bolivina dilatata, and otherBolivina species during intervals corresponding to the episodic abyssal stagnation events. Some cores also display a decrease inCassidulina carinata and an increase inArticulina tubulosa.Similar assemblage changes have been previously documented to be closely associated with the sapropel layers in the deep basins of the eastern Mediterranean (the actual sapropel layers usually do not contain benthonic foraminifera). However, in the Strait of Sicily area, the species exhibit less drastic changes than in the deep eastern basins because of the less severe anoxic conditions. In the deep eastern basins, benthonic foraminifera almost totally disappeared in sapropel layers; at the same time, there was a general reduction in foraminiferal numbers in the shallower Strait area.     

Distribution of arenaceous foraminifera in depth profiles of the Southern Ocean (kerguelen plateau area)

Recent to subrecent benthonic arenaceous foraminifera from two areas of the Southern Ocean have been investigated with regard to their depth distribution and agglutination patterns. Strong differences exist between the arenaceous faunas from (a) diatomaceous sediments west of the Kerguelen Plateau and (b) glacial marine sediments from the slope of the Antarctic continent. Major ecologic influences are seen in the effect of sedimentological factors (especially the clay content of the sediment), in the saturation level of calcium carbonate and in the nutrient condition of the biotope. Since these factors are a function of geographic position and related water masses, the main differences of deep-sea faunas are primarily induced by the overall situation of an oceanic area rather than by depth or oceanographic factors like temperature or salinity. Availability of colloidal iron compounds also seems to be a limiting factor for distinct arenaceous species.     

Diplobulbus brayi n. sp. (Digenea: Opecoelidae) from Odax acroptilus (Perciformes: Odacidae) off Western Australia

Diplobulbus brayi n. sp. is described from the small intestine of Odax acroptilus (Perciformes: Odacidae) from Point Peron in southern Western Australia. One of the five previously described species of Diplobulbus, D. vitellosus Bilqees, 1972 from Tetraodon lunaris (now Lagocephalus lunaris), is synonymised with Alloheterolebes indicus (Gupta, 1968) Hafeezullah, 1971, which is known from the same host in the Indian Ocean. D. brayi n. sp. can be distinguished from the remaining four species of Diplobulbus by the distinct interruption of the vitelline follicles at the ventral sucker, its more elongate form and its long post-testicular space. Diplobulbus is so far restricted to the Indo-Pacific region and appears to be stenoxenic to labroid fishes. This is the first record of a trematode from an odacid fish.     

Dactylomyza gibsoni n. g., n. sp. (Digenea: Opecoelidae) from Schuettea woodwardi (Waite) (Monodactylidae) from off Western Australia

An opecoelid digenean, Dactylomyza gibsoni n. g., n. sp. is described and figured from Schuettea woodwardi (Waite), a monodactylid from off the coast of Western Australia. The new genus conforms to the concept of the opecoelid subfamily Opecoelinae. The resemblance of the new genus to three other opecoelid genera, Pseudopecoeloides Yamaguti, 1940, Opecoeloides Odhner, 1928 and Poracanthium Dollfus, 1948, is discussed. Dactylomyza n. g. is distinguished from these morphologically similar worms on the basis of its median genital pore, ventral sucker appendages, uroproct and the absence of an accessory sucker. Pseudopecoeloides equesi Manter, 1947 is transferred to the new genus as Dactylomyza equesi (Manter, 1947) n. comb.     

A new species of Darwinia (Myrtaceae) from Western Australia

A new species of Darwinia, D. divisa is described. The species is unique in the genus in having divided prominent calyx lobes and densely hairy floral tube. The species has not been re-collected since the type and only collection in 1965.     

A new genus of Syllidae (Polychaeta) from Western Australia

During a study carried out on the subfamily Exogoninae (Syllidae) from Australia, several specimens of a new genus and species were found in samples of dead coral substrate from Western Australia. They have long palps, fused except for a terminal notch, long median and two short lateral antennae, a single pair of short tentacular cirri, and short dorsal cirri, somewhat longer than the parapodial lobes. These characters resemble those of the genus Exogone Örsted, 1845. However, all these appendages are articulated. The chaetae are very similar to those of several species of Syllis Lamarck, 1818, having coarse spines on the margin of compound chaetal blades and truncated dorsal simple chaetae. Furthermore, the pharynx begins in chaetiger 3, posterior to the peristomium, as in many species of the genus Syllis; this condition does not occur in any described species of Exogone. The new genus is provisionally proposed to belong to the subfamily Syllinae, although it has some characters typical of the Exogoninae. Examination under the SEM shows another peculiar feature, the nuchal organs are distinctly laterally located. Within the Syllinae, only Paratyposyllis Hartmann-Schröder, 1962 has a single pair of tentacular cirri, but in that genus, the palps are only basally fused.     

Food habits of the sandpaper skate, Bathyraja kincaidii (Garman, 1908) off central California: seasonal variation in diet linked to oceanographic conditions

The stomachs of 130 sandpaper skates, Bathyraja kincaidii (Garman, 1908), were sampled from off central California to determine their diet composition. The overall diet was dominated by euphausiids, but shrimps, polychaetes and squids were also important secondary prey. A three-factor MANOVA demonstrated significant differences in the diet by sex, maturity status and oceanographic season using numeric and gravimetric measures of importance for the major prey categories. These three main factors explained more variation in diet than interactions between the factors, and season explained the most variance overall. A detailed analysis of the seasonal variation among the prey categories indicated that abundance changes in the most important prey, euphausiids, were coupled with seasonal changes in the importance of other prey. When upwelling occurred and productivity was great (Upwelling and Oceanic seasons), euphausiids were likely highly abundant in the study area and were the most important prey for B. kincaidii. As productivity declined (Davidson Current season), euphausiids appeared to decrease in abundance and B. kincaidii switched to secondary prey. At that time, gammarid amphipods and shrimps became the most important prey items and polychaetes, mysids and euphausiids were secondary.     

Microplankton response to environmental conditions in the Alboran Sea (Western Mediterranean): One year sediment trap record

The present work analyses the seasonal evolution of planktonic assemblages and particle fluxes through the water column in the Eastern Alboran Sea (Western Mediterranean) at 35º55.47'N/01º30.77'W. A Sediment trap was deployed below the influence of the Almeria-Oran Front (AOF), a semi-permanent geostrophic front, during July 1997 to June 1998. Overall, the temporal variability of coccolithophore, planktonic foraminifer, diatom, benthic and wind-carried biogenic particle fluxes is linked to the seasonal evolution of sea surface hydrological structures. Maximum planktonic fluxes were found during high-productivity periods and wind-induced upwelling, following a trimodal pattern, with maximum fluxes in July 1997, November–December 1997, and April–May 1998. These periods were characterized by vertical mixing and the full development of anticyclonic gyres in the Alboran Sea. The annual flux of coccolithophores was dominated by the “small Gephyrocapsa Group” and Emiliania huxleyi, whereas Turborotalita quinqueloba and Globigerina bulloides dominated the foraminiferal fluxes, and Chaetoceros Resting Spores (RS) were predominant in the diatom assemblage. Benthic specimens were also collected with the sediment trap, suggesting a variable influence of bottom water activity. Wind-driven particles (phytoliths and fresh-water diatoms) were collected along the year, but their fluxes followed the local wind regime.The high Sea Surface Temperature (SST) during fall due to weaker than usual westerly winds, and the pressure anomaly prevailing in the Alboran Sea during early winter, were reflected in the planktonic assemblages by the proliferation of warm, lower photic layer inhabitants and/or oligotrophic taxa of coccolithophores (Florisphaera profunda), planktonic foraminifers (Globigerinoides ruber and Globorotalia inflata) and diatoms (Leptocylindrus danicus). These unusual climatic conditions in the eastern Alboran Sea must have been caused by the 1997–1998 ENSO event.     

Bathymetric distribution of fossil foraminifera within marine sediment cores from the eastern part of Lützow-Holm Bay, East Antarctica, and its paleoceanographic implications

Faunal analysis of fossil foraminifera from marine gravity and piston cores collected by the Japanese Antarctic Research Expeditions (1981 and 1992) is used to estimate the impact of the latest Quaternary paleoceanography on coastal environments of the eastern part of Lützow-Holm Bay, East Antarctica.Accelerator Mass Spectrometry (AMS) carbon-14 ages produced from sedimentary organic carbon were less than 16 ka (non-corrected). Detailed correlation among submarine cores and Holocene elevated marine deposits exposed on the eastern shore of the embayment is difficult due to the indefinite reservoir correction value for marine organic matter and to upward-increasing abnormal ages for some cores.A local carbonate dissolution level can be delineated around the present depth of 300–400 m or shallower in the eastern part of Lützow-Holm Bay during the Holocene, based on distributional trends of arenaceous, calcareous benthic, and planktonic foraminifera recognized within a depth less than 600 m. Downcore recovery of calcareous foraminifera containing Bulimina aculeata from two cores obtained in a drowned glacial trough deeper than 600 m situated far beyond the dissolution depth of CaCO₃ indicates the incursion of warm, high-nutrient, and CaCO₃-saturated Circumpolar Deep Water (CDW) from the offshore area along the trough toward the southeastern coast of Lützow-Holm Bay during the Holocene. The intrusion of CDW impacted on the marine environments of the southeastern coast, thereby contributing to peripheral retreat of the ice sheet as well as increasing calcareous benthic foraminiferal productivity along the southeastern coast of Lützow-Holm Bay.     

Coxiella burnetii in Western Barred Bandicoots (Perameles bougainville) from Bernier and Dorre Islands in Western Australia

The aim of this work is to investigate the presence of Coxiella burnetii in Perameles bougainville and their ticks on two islands off Western Australia. Haemaphysalis humerosa, Haemaphysalis ratti, and Haemaphysalis lagostrophi were collected from P. bougainville on Bernier and Dorre Islands from 2005 to 2007; only Amblyomma limbatum was collected from humans over the same interval. One of 13 tick samples and 1 of 12 P. bougainville fecal samples were positive for C. burnetii DNA using quantitative polymerase chain reaction. DNA fragments had >99% similarity to published C. burnetii sequences. Three of 35 P. bougainville sera tested positive for anti-C. burnetii antibodies using enzyme-linked immunosorbent assay. C. burnetii was found in P. bougainville feces and a H. humerosa tick on Dorre Island and Bernier Island, respectively. This is the first reported use of enzyme-linked immunosorbent assay for screening of P. bougainville sera. The risk of zoonotic Q fever infection for human visitors to these islands is considered relatively low, however, appropriate precautions should be taken when handling western barred bandicoots, their feces and their ticks on Bernier and Dorre Islands.     

Planktonic foraminifera from the eastern Indian Ocean: distribution and ecology in relation to the Western Pacific Warm Pool (WPWP)

Faunal assemblages, principal component (PCA), canonical correspondence (CCA), and factor analysis are applied to planktonic foraminifera from 57 core-top samples from the eastern Indian Ocean. The foraminiferal lysocline occurs at 2400 m north of 15°S where carbonate dissolution is induced by the Java upwelling system, and occurs deeper south of 15°S where carbonate dissolution is characteristic of the oligotrophic regions in the Indian Ocean. Dissolution effects, the February standing stock at the time of collection of the plankton-tow material, and different production rates explain the different foraminiferal assemblages found between plankton-tow and core-top samples. Core-top samples are differentiated by PCA into four groups — Upwelling, Western Pacific Warm Pool (WPWP), Transitional, and Southern — that are related to environmental variables (temperature, salinity and nutrients); all environmental variables follow a strong latitudinal component as indicated by the CCA analysis. Similarly, three assemblages are recognized by factor analysis: Factor 1 (dominated by Globigerinoides sacculifer, G. ruber, Globigerinita glutinata and Globorotalia cultrata), factor 2 (dominated by Globigerina bulloides and Globorotalia inflata) and factor 3 (dominated by Neogloboquadrina dutertrei) explain more than 92% of the variance, and are related to sea-surface temperature, thermocline depth and nutrient levels. The seasonal influence of the Java upwelling system supplies nutrients, phyto- and zooplankton to the oligotrophic eastern Indian Ocean (factor 1). South of 24°S, a deep chlorophyll maximum, a deep euphotic zone, a deep thermocline, SSTs below 22°C, and brief upwelling pulses seem to explain factors 2 and 3. The ratio of G. sacculifer and N. dutertrei, two mutually excluding species, appears to indicate the southern boundary of the WPWP. This ratio is applied to core Fr10/95-11 to demonstrate past shifts of the southern boundary of the WPWP.     

Two new opecoelids (Digenea) in the flatfish Pseudorhombus jenynsi (Bleeker) from Shark Bay,Western Australia

The first marine fish digeneans recorded from Shark Bay, Western Australia are described from the flatfish Pseudorhombus jenynsi. Macvicaria dampieri n. sp. differs from the other members of the genus in its undivided, straight, saccular seminal vesicle, and the definition of the genus is extended to include this feature. The following new combinations are made: Macvicaria branchiostegi (Yamaguti, 1937) [originally Plagioporus] and M. cynoglossi (Madhavi, 1975) [originally P.]. Cainocreadium alanwilliamsi n. sp. is distinguished by the variable anterior extent of its excretory vesicle, which reaches to a level ranging between the posterior margin of the ventral sucker and just into the forebody, and by its relatively short forebody.     

Paralepidapedon ostorhinchi (Korotaeva, 1974) n. comb. (Digenea: Lepocreadiidae) in Oplegnathus woodwardi (Waite) (Teleostei: Perciformes: Oplegnathidae) from off Rottnest Island,Western Australia

The digenean originally designated Lepidapedon (Lepidapedon) ostorhinchi is redescribed from its type-host, Oplegnathus woodwardi [= Ostorhinchus conwaii], from the waters off Western Australia. The discovery of a uroproct indicates that the generic designation is wrong and the worm should be Paralepidapedon ostorhinchi (Korotaeva, 1974) n. comb. It is distinct from its nearest relative, P. hoplognathi (Yamaguti, 1938), in having: a prominent post-oral ring; a distinct oesophagus; short anterior diverticula on the caeca; a long external seminal vesicle, ensheathed in a membrane bound gland-cell mass; and less anteriorly extensive vitellarium.     

A new species of Bentleya. Bennett (Pittosporaceae) from southern Western Australia

CRISP, M. D. & TAYLOR, J. M., 1990. A new species of Bentleya E. Bennett (Pittosporaceae) from southern Western Australia. Hitherto Bentleya has been a monotypic genus known from a restricted area in south-west Western Australia. This paper describes a second species which was discovered recently in the same region. The new species differs from B. spinescens in its remarkable habit but shares with it several floral characters which are unique within the family.     

Surface water conditions in the Northern Benguela Region (SE Atlantic) during the last 450 ky reconstructed from assemblages of planktonic foraminifera

Planktonic foraminiferal records from Site 1083 (ODP Leg 175) were used to investigate changes in surface water conditions in the Northern Benguela Region over the past 450 ky. The assemblages of planktonic foraminifera are dominated by four species: sinistral coiling Neogloboquadrina pachyderma, dextral coiling N. pachyderma, Globigerina bulloides and Globorotalia inflata. Besides, tropical species deliver a small contribution to the assemblage.The most prominent temporal variations, displayed by N. pachyderma (s+d), represent changes in the coastal upwelling and the presence of cold, nutrient rich waters over the core site. Neogloboquadrina pachyderma (s+d) shows cyclic variability in the eccentricity and, to a less extent, precession frequencies. The changes indicate increased upwelling intensity in glacial maxima and precession maxima, and correlate well with the wind-strength record of Stuut et al. (2002). During glacial maxima, steep temperature gradients over the Southern Hemisphere caused strong SE trade winds and strong upwelling. Precession maxima cause a weak monsoonal circulation, more zonal SE trade winds, strong coastal upwelling, and nutrient-rich surface waters over ODP Site 1083.Advection of Angola Current (AC) surface water into the Walvis Basin, indicated by the tropical species, occurs when the Angola Benguela Front (ABF) is positioned southward. Occasionally, this happened during glacial maxima, as can be explained with the reconstructed and predicted meridional movements of the ABF. The amount of AC water was never sufficient to suppress the marine biological production at the core site.The contribution of Benguela Current (BC) water, reflected by Globorotalia inflata, is greatly determined by the upwelling. In periods of strong upwelling, the BC influence is suppressed.In several glacial substages, the temperature of the upwelling South Atlantic Central Water (SACW) may have been increased, as suggested by the dominance of Neogloboquadrina pachyderma (d) in the upwelling record. This phenomenon may be due to intensified subduction in the central South Atlantic that induces the formation of SACW, or to larger contributions of Eastern SACW to the upwelling water.Around 250–200 ky BP, a long-term shift to higher productivity occurred that is absent in the upwelling record. It was accompanied with a transition from a precession and obliquity variability to an eccentricity dominated variability in the Globorotalia inflata (BC) record. The shift was probably connected to a long-term southward shift of the circumpolar oceanic frontal systems south of the African continent.     

Metabolic enzyme activities in black bream (Acanthopagrus butcheri) from the Swan-Canning Estuary, Western Australia

The Swan-Canning estuary, in southwestern Australia, is subject to frequent algal blooms and associated periods of hypoxia due to high levels of nutrients in stormwater runoff and sewage spills. Fish in which cellular respiration is impaired due to chronic exposure to non-nutrient pollutants in the water will have a reduced ability to survive these periods of high stress. In order to investigate if metabolic respiration in black bream (Acanthopagrus butcheri) was altered, fish were collected from five sites in the Swan-Canning estuary in summer 2001, summer 2002 and winter 2002. Aerobic and anaerobic capacities were estimated by measuring the enzymes cytochrome C oxidase (CCO) and lactate dehydrogenase (LDH). Neither seasonal or annual trends, nor upstream or downstream gradients were observed in either biomarker. The fish collected from the Barrack Street site, which is close to the Perth Central Business District, were heavily challenged in their aerobic capacity in the summer months compared to the other sites. In addition, the fish at Barrack Street displayed an altered anaerobic capacity. It is likely that the impaired metabolic capacity of the fish at Barrack Street reduces the fishes' ability to survive the frequent algal blooms within the estuary.