Sublittoral Species Research Articles

New sublittoral species of Laonice (Annelida: Spionidae) from southern Asian coasts.

Four new species of Laonice (Annelida: Spionidae) are described from the southern and southeastern coasts of Asia: L. (Laonice) persica sp. nov., L. (Laonice) siamica sp. nov., L. (Sarsiana) apicelamella sp. nov. and L. (Sarsiana) andamanica sp. nov. Materials were collected within the scope of different environmental surveys performed by the consulting company Créocéan, ranging from the Persian Gulf (Indian Ocean) on the west, to the Gulf of Siam (Pacific Ocean) on the east. In addition, specimens found in the Gulf of Siam are tentatively attributed to L. (Sarsiana) sinica, and an English translation of the species description is provided for the first time. Different species subgroups within L. (Sarsiana) are also recognized based on key morphologic characters, though their phylogenetic relevance requires further confirmation. The scientific value of biological material collected during environmental surveys is emphasized, and contractors are encouraged to deposit reference collections in public natural history collections.

Advancing quantification methods for polyphenols in brown seaweeds-applying a selective qNMR method compared with the TPC assay.

Brown seaweeds are a sustainable biomass with a potential for various industrial applications. Polyphenols are an important contributor to this potential. The aim was total quantification of polyphenols in brown seaweeds from different tidal zones, using a selective 1 H quantitative NMR (qNMR) method, comparing the results with the colorimetric Folin-Ciocalteu total phenolic content (TPC) assay. qNMR was performed with integration of selected peaks in the aromatic region (7-5.5 ppm). Deselection of non-polyphenolic 1 H signals was based on information from 2D (1 H-13 C, 1 H-15 N) NMR spectra. 13 C NMR phlorotannin characterisation facilitated the average number of protons expected to be found per aromatic ring used for the 1 H quantification. Selective qNMR and the TPC assay showed similar results for the three sublittoral growing species from the Laminariaceae; lower amounts for Laminaria hyperborea and Laminaria digitata (qNMR: 0.4%-0.6%; TPC: 0.6%-0.8%, phloroglucinol equivalents (PGE), dry weight (DW)) and higher amounts for Saccharina latissima (qNMR: 1.2%; TPC: 1.5%, PGE, DW). For the eulittoral Fucaceae, Fucus vesiculosus (qNMR: 1.1%; TPC: 4.1%; PGE, DW) and Ascophyllum nodosum (qNMR: 0.9%; TPC: 2.0%; PGE, DW), the TPC results were found to be up to three times higher than the qNMR results. The 13 C NMR characterisation showed the highest phlorotannin polymerisation degree for F. vesiculosus. The TPC assay provided similar polyphenolic amounts to the selective qNMR method for sublittoral species. For eulittoral growing species, the TPC method showed amounts up to three times higher than the qNMR method-most likely illustrating the lack of selectivity in the TPC assay.

Benthic Peracarids (Crustacea) from an unexplored area of Patagonian channels and Fjords.

BackgroundThe intricate geomorphology of the coastline in the Chilean Channels and Fjords region, together with the freshwater inputs from the ice fields provide the area with very unique ecological characteristics and a variety of habitats that favour great marine biodiversity. However, although Chilean Patagonia has been the focus of several expeditions and ecological surveys, the greatest emphasis has been either on the populated coasts of the Beagle Channel and the Straits of Magellan to the south or the area to the north of Golfo de Penas, leaving vast areas that remain largely unexplored. This leads to a latitudinal gap in the faunistic information and hinders zoogeographic studies to assess biogeographical connections along the eastern coasts of the Pacific. Peracarida is a taxonomic group that provides an excellent model for such studies because of their high abundance and biodiversity, benthic habits, small size and limited dispersal capacity.New informationA dataset providing the first and only records of the benthic Peracarida between the latitudes 48–51.5°S of the Pacific coast of Chile is presented here, hence closing a geospatial gap for the study of the biogeographical connections of the Peracarida along the Eastern Pacific coast. The dataset comprises a total of 141 georeferenced records of 60 sublittoral species of Tanaidacea, Isopoda and Amphipoda. This and other studies reveal that the coastal fauna of the region follow a latitudinal distribution pattern at a larger scale and nested assemblages inside the channels and fjords that can be regarded as a consequence of the more restrictive conditions in the inner parts. In the present scenario of global warming that is expected to affect particularly polar and subpolar regions, the present dataset serves as a reference for the distribution patterns of benthic organisms with low dispersal capacity.

Features of the Species and Spatial Structure of Macrobenthos in the Green Cape Lagoon (Kandalaksha Bay, White Sea)

Features of the species and spatial structure of macrobenthic sublittoral communities in a lagoon ecosystem on the Green Cape (the White Sea) were studied. 31 invertebrate species and 3 species of sea grasses and algae (Zostera marina, Cladophora sericea, and Fucus vesiculosus) were found in the sublittoral of the surveyed lagoon. The data on the species composition, diversity and spatial structure of macrobenthos communities indicate the predominance of littoral brackish-water and marine euryhaline macrobenthos species (Hydrobia ulvae, Tubificoides benedii, Chironomus salinarius, and Macoma balthica) in the coastal region of the lagoon, marine euryhaline littoral and sublittoral species (mainly polychaetes Heteromastus filiformis, Polydora ciliata, and Capitella capitata) in the central deeper region, and marine sublittoral less euryhaline species (Pontoporeia femorata, Anonyx nugans, Nereimyra punctata, Terebellides stroemi, Astarte montagui, Micronephthys minuta, and Atylus carinatus) at the exit from the lagoon. The ecosystem of the Green Cape lagoon belongs to lagoons significantly fenced off from the sea with depleted specific fauna (many littoral species) and largely influenced by carbon load and salinity. The reduced connection of the lagoon with the sea due to the continued rise of the White Sea coast (4 mm per year in this area) will contribute to a decrease in the species diversity and the predominance of few small eurytopic invertebrate species resistant to organic load, oxygen deficiency, and desalination.

Some Features of the Species, Spatial, and Trophic Structure of Macrobenthos in the Lagoon Systems of the Ermolinskaya and Nikol’skaya Inlets (Kandalaksha Bay, the White Sea)

The features of the species, spatial, and trophic structure of macrobenthic sublittoral communities were studied in two coastal lagoon ecosystems of the White Sea. The Ermolinskaya and Nikol’skaya inlets are highly silted lagoon ecosystems with a simplified trophic structure of the macrobenthos community and a predominance of the trophic group of collecting detritophages. In the sublittoral of the studied lagoons, 24 species of invertebrates, as well as four species of marine higher plants and algae (Zostera marina, Cladophora sericea, Fucus vesiculosus, and Chorda tomentosa), were found. The lagoon ecosystem of the Ermolinskaya Inlet was characterized by the highest species diversity, total density, and biomass of species populations of macrobenthos, while the ecosystem of the Nikol’skaya Inlet was characterized by lower indices. In the lagoon of the Nikol’skaya Inlet, which was better protected from the sea waves and currents, a greater development of littoral euryhaline marine and brackish-water species of macrobenthos was observed, while more marine sublittoral species were found in the lagoon of the Ermolinskaya Inlet, which is less protected from the sea.

Metabolomics based on UHPLC-QToF- and APGC-QToF-MS reveals metabolic pathways reprogramming in response to tidal cycles in the sub-littoral species Mimachlamys varia exposed to aerial emergence

Mimachlamys varia is a sub-littoral bivalve encountered from Norway to the Mediterranean Sea, which lives mostly byssally attached to rocks. During the low tide period, M. varia individuals, located highest on the shore, may experience short time of aerial exposure and face a low availability of oxygen. Here we report a comparative metabolomic profiling of gill samples of M. varia obtained by both LC-QToF and APGC-QToF mass spectrometry, to analyze metabolic changes occurring during emersion in comparison with immersion. Scallops were grown in aquaria with a simulated intertidal environment mimicking short-duration air exposure that they might experience during extreme tides: alternating 2 h emersion and 10 h immersion. Our results show a switch from aerobic to anaerobic metabolism after only 2 h of emersion, with the resort to different pathways: glucose-lactate, glucose-succinate and aspartate-succinate pathways. Furthermore, carnitine-conjugated metabolites were found to accumulate during emersion, as well as urate. The level of tyrosine on the contrary was found to decrease. These findings indicate a complex metabolic reprogramming that occurs after a two hour emersion period and upon re-immersion. Furthermore, M. varia is used as sentinel species in pollution biomonitoring, through the assay of biomarkers to evaluate the effects of pollutants. Here we show that emersion induces a significant decrease of superoxide dismutase activity, an enzyme developed by bivalves to face oxidative stress and used as biomarker. These findings have to be taken into account to normalize sampling during campaigns of environmental monitoring, by taking in situ, as far as possible only immersed individuals.

Two new European species of the marine genus Tubificoides (Annelida: Clitellata: Naididae) with notes on the morphology of T. pseudogaster (Dahl, 1960)

Two new species of Tubificoides (subfamily Tubificinae), T. charlotteae n. sp. and T. mackiei n. sp., are described based on morphological analyses. Both species were flagged as potentially cryptic in a previous investigation, based on both mitochondrial and nuclear sequence data. Tubificoides charlotteae n. sp., known only from an intertidal site in southern Spain, is characterized by the lack of cuticular papillation, the possession of several needle-like hair chaetae in dorsal bundles, a cone-shaped penis sheath, and a rather large, muscular penial sac. It strongly resembles the north-west European, largely sublittoral species T. amplivasatus, but differs from this species in terms of body size, width of vas deferens, and the shape and size of both the ejaculatory duct and penial sac. Tubificoides mackiei n. sp., collected from the southeast coast of Norway and the west coast of Sweden, is characterized by the lack of cuticular papillae and hair chaetae, and the possession of a rather long penis sheath with a wide terminal opening. It shares several morphological features with the sympatric species Tubificoides pseudogaster, but is distinguished from the latter by the detailed morphology and length of the penis sheaths, the width of the atrium, and the lower maximal number of bifid chaetae in dorsal preclitellar bundles. The utility of an integrative comparative approach, combining molecules and morphology, for the identification and delineation of new taxa within Tubificoides is briefly discussed.

Comparison of Ichthyofauna Composition in Different Areas of Russian and Korean Waters in Sea of Japan/East Sea

The specificity of the species composition of the ichthyofauna in the Russian and Korean waters in the Sea of Japan/East Sea (northwards from 35°17′N) is considered. The population and the proportion of species from the order of the perch-like fishes (Perciformes) steadily decline from the south towards the north; the proportion of the species from the order of the ray-finned fish (Scorpaeniformes) tends to rise. The northward latitudinal gradient in the family composition variability results in a decrease of their numbers along with a significant increase in the sculpins (Cottidae) and the picklebacks (Stichaeidae) in the species composition. In the southernmost region of the studied water area, the sublittoral species tend to prevail; in all of the others, the elittoral species are predominant. The four northern areas are characterized by a high similarity in the species composition (81.8%); this value is significantly lower (63.1%) in case of their comparison with the more southern areas. The similarity in the ichthyofauna composition between the southernmost area and the other studied water area comprises 44.1%.

Stress tolerance of Antarctic macroalgae in the early life stages

Early life stages of macroalgae, especially from polar species, can be highly vulnerable to physical stressors, leading to important consequences for the fate of the whole population in scenarios of changing environmental variability. In the present study, tolerance to UV and temperature stress, as measured by rapid adjustment of photochemistry, Fv/Fm, and photosynthetic characteristics based on P-E curves (ETRmax, α and Ek), was assessed in the early life stages of six Antarctic macroalgal species from eulittoral (Pyropia endiviifolia, Iridaea cordata, Adenocystis utricularis and Monostroma hariotii) and sublittoral (Ascoseira mirabilis and Gigartina skottsbergii). Reproductive cells of eulittoral species showed the highest light demands (Ek >45 μmol photon m−2 s−1) when compared to those from sublittoral species (Ek 30 % inhibition in Fv/Fm in the same condition. Enhanced temperature (7 and 12 °C) improved the tolerance of I. cordata compared to 2 °C, but exacerbated the detrimental effects of UV on A. mirabilis. Results showed that photosynthetic characteristics varied among reproductive cells of different species, reflecting the vertical zonation of parental thalli. Otherwise, these differences appear to underlie biogeographical and evolutionary components. In addition, UV tolerance was modulated by temperature increase, while temperature increase, in turn, ameliorated the detrimental effects of stress treatments in some eulittoral species (I. cordata tetraspores). In sublittoral A. mirabilis gametangia, temperature exacerbated the reduction of photosynthetic efficiency.

On the brink of the Arctic: Unusual intertidal sub-Arctic kelp associations in the Porsangerfjord, North Norway

The kelps Laminaria digitata and Saccharina latissima are typically sub-littoral species. It is therefore surprising to find large intertidal kelp beds dominated by these two species in the inner Porsangerfjord, North Norway. The areas of the nine intertidal kelp beds ranged from 0.01 to 3 km2 and covered a total area of 8.3 km2. Both species had a prostrate growth form with short stipes, usually less than 10 cm long, independent of the length of the lamina. The laminae of L. digitata and S. latissima measured 77.0 ± 35.2 cm and 99.4 ± 41.0 cm (mean ± 1 SD), respectively. The associations occurred in sheltered areas with a muddy bottom on wide, flat areas of moraine. The areas are completely drained at low tide. The holdfasts were attached to small pebbles sunk in the mud. The mean biomass density of the two dominant kelp species was 4.1 ± 1.8 kg m−2. The mean biomass of all the algal species in the association was 6.1 ± 2.2 kg m−2. A total of 32 species were identified in the association, of which 16 species were annuals and 16 were perennials. All the species found in the kelp associations are also found in the Arctic. The prostrate growth form of L. digitata and S. latissima, the topography and substrate of the intertidal zone, low summer temperatures, low desiccation and protective sea ice during winter are possible factors contributing to the formation of these unusual intertidal kelp associations.

Shellfishing and the Colonization of Sahul: A Multivariate Model Evaluating the Dynamic Effects of Prey Utility, Transport Considerations and Life-History on Foraging Patterns and Midden Composition

ABSTRACTArchaeological evidence of shellfish exploitation along the coast of Sahul (Pleistocene Australia-New Guinea) points to an apparent paradox. While the continental record as a whole suggests that human populations were very low from initial colonization through early Holocene, coastal and peri-coastal sites dating to that time are dominated by small, low-ranked, littoral taxa to the near-complete exclusion of large, higher ranked, sub-littoral species, precisely the opposite of theory-based expectations, if human populations and predation rates were indeed as low as other data suggest. We present a model of shellfish exploitation combining information on species utility, transport considerations, and prey life-history that might account for this apparent mismatch, and then assess it with ethnographic and archaeological data. Findings suggest either that high-ranked taxa were uncommon along the Pleistocene coastlines of Sahul, or that abundant and commonly taken high-ranked prey are under-represented in middens relative to their role in human diets largely as a function of human processing and transport practices. If the latter reading is correct, archaeological evidence of early shellfishing may be mainly the product of subsistence activities by children and their mothers.

Deposits of the Tohoku Tsunami (March 11, 2011) in the southern Kuril Islands: Composition and fossils

The deposits of the Tohoku Tsunami were studied on the Kunashir, Shikotan, Zelenyi, Yurii, and Tanfil’ev islands. They were sampled immediately after this event from ice, half a year later, and one and a half years later. The sampling was accompanied by measurements of the runup heights and the description of the innudation zones. Sand and mud covers were recorded only in closed bays that were covered by ice. The tsunami waves broke the ice cover to provoke bottom erosion and peatland destruction in low coastal areas even under insignificant runup. The investigations included the analysis of the grain-size distribution in the deposits and the taxonomic composition of the microfossils, including benthic foraminifers, diatoms, and pollen assemblages. The marine diatom assemblages are dominated by sublittoral benthic forms accompanied by subordinate sublittoral planktonic, neritic, and oceanic species. The palynospectra include pollen and spores of the local island vegetation, allochthonous pollen transported by the tsunami wave and wind from adjacent areas, and taxa reworked from the upper Holocene deposits eroded by the tsunami. The examined sections have been revisited to estimate the degree of preservation of the tsunamigenic deposits.

Temperature effects on metabolic rate and cardiorespiratory physiology of the spiny rock lobster (Jasus edwardsii) during rest, emersion and recovery

Although spiny rock lobster (Jasus edwardsii) is a wholly sub-littoral species, they show a considerable ability to survive prolonged emersion, a fact exploited during the commercial export of this species. Yet, despite this remarkable hardiness, basic information on how this species responds physiologically to emersion is somewhat lacking. Using flow-through respirometry and electrophysiological techniques, we identified that J. edwardsii undergoes marked physiological changes during rest, emersion and recovery over a broad range of temperatures (3.7-17.8°C). Under resting conditions, routine metabolic rates (RMR) were 22.57±2.39, 9.69±0.55 and 8.09±0.27mL O2 h(-1), average heart rates (Hr) were 54.72±4.46, 37.68±2.86 and 29.67±0.59 BPM, and ventilation frequencies were 83.71±5.86, 45.34±2.91 and 41.62±0.65 BPM at 15.0, 7.5 and 3.7°C, respectively. Notably, the surgical implantation of electrodes elevated RMR compared with non-surgical treatments. In surgery and non-surgery groups, Q 10 was calculated to be ca. 3.0. Upon emersion, rate of oxygen consumption and Hr decreased below resting rates in a temperature-dependent manner, but, along with rate of CO2 production, increased steadily during 24-h emersion. Ventilation frequencies upon emersion showed a contrasting response and increased significantly above resting rates. When returned to flow-through sea water for recovery, elevated respiration rates provided clear evidence of an O2 debt, and near-complete recovery was observed after 17h at both 15.0 and 7.5°C, but close to no debt was recovered at 3.7°C. In addition, J. edwardsii was observed to undergo marked diurnal and periodic ventilation cycles, characterised by synchronous changes in RMR, Hr and ventilation frequency.

Life histories and distribution of ostracods with depth in western Lake Geneva (Petit-Lac), Switzerland: a reconnaissance study

Because environmental conditions within a given basin are different for each season and at different water depth, knowledge of the life history and depth distribution of target species is important for environmental and palaeoenvironmental interpretations based on ostracod species assemblages and/or the geochemical compositions of their valves. In order to determine the distribution of species with depth as well as the life history of species from Lake Geneva, a one-year sampling campaign of living ostracods was conducted at five sites (2, 5, 13, 33 and 70 m water depth) on a monthly basis in the Petit-Lac (western basin of Lake Geneva, Switzerland). Based on the results, the different species can be classified into three groups. Littoral taxa are found at 2 and 5 m water depth and include, in decreasing numbers of individuals,Cypridopsis vidua(O. F. Müller, 1776),Pseudocandona compressa(Koch, 1838),Limnocythere inopinata(Baird, 1843),Herpetocypris reptans(Baird, 1835),Potamocypris smaragdina(Vávra, 1891),Potamocypris similis(G. W. Müller, 1912),Plesiocypridopsis newtoni(Brady & Robertson, 1870),Prionocypris zenkeri(Chyzer & Toth, 1858) andIlyocyprissp. Brady & Norman, 1889. Sublittoral species are found in a majority at 13 m water depth and to a lesser extend at 33 m water depth and include, in decreasing numbers of individuals,Fabaeformiscandona caudata(Kaufmann, 1900),Limnocytherina sanctipatricii,Candona candida(O. F. Müller, 1776) andIsocypris beauchampi(Paris, 1920). Profundal species are found equally at 13, 33 and 70 m water depth and includes, in decreasing numbers of individuals,Cytherissa lacustris(Sars, 1863),Candona neglectaSars, 1887 andCypria lacustrisLilljeborg, 1890. The occurrence ofLimnocytherina sanctipatricii(Brady & Robertson, 1869) is restricted from late winter to late spring when temperatures are low, whileC. vidua,L. inopinata,P. smaragdina,P. similis,P. newtoniandIlyocyprissp. occur predominantly from spring to early autumn when temperatures are high. Individuals ofC. neglecta,C. candida,F. caudata,P. compressa,C. lacustris,H. reptansandCp. lacustrisoccur throughout the year with juveniles and adults occurring during the same period (C. neglectaat 70 m,C. lacustrisat 13, 33 and 70 m, andH. reptansat 2, 5 and 13 m water depth) or with juveniles occurring during a different period of the year than adults (C. neglectaat 13 and 33 m andC. candida,F. caudataandP. compressaat their respective depth of occurrence). Among the environmental parameters investigated, an estimate of the relationship between ostracod autoecology and environmental parameters suggests that in the Petit-Lac: (i) water temperature and substrate characteristics are important factors controlling the distribution of species with depth, (ii) water temperature is also important for determining the timing of species development and, hence, its specific life history, and (iii) water oxygen and sedimentary organic matter content is less important compared to the other environmental parameter monitored.

Metopelloides paguri sp. nov., a new species of symbiotic stenothoid amphipod (Crustacea: Amphipoda: Stenothoidae) associated with sublittoral hermit crabs from the Russian coasts of the Sea of Japan

A new species of amphipod from the genus Metopelloides Gurjanova, 1938 (Crustacea: Amphipoda: Stenothoidae) asso-ciated with two species of sublittoral hermit crab species, Pagurus pectinatus (Stimpson, 1858) and Elassochirus cavi-manus (Miers, 1879) (Crustacea: Decapoda: Paguridae), is described from the Russian coasts of the Sea of Japan. The newspecies clearly differs from the congeners by the combination of morphological features such as telson without lateralspines, an elongated mandibular palp with single apical setae, the structures of distoventral palmar margins of subchelaon gnathopods I and II in females, bright white-red body coloration. Thus, the record of Metopelloides paguri sp. nov.represents the second record of the family Stenothoidae in the association with sublittoral hermit crabs from the Sea of Japan.

Benthic Foraminiferal Biogeography: Controls on Global Distribution Patterns in Deep-Water Settings

Benthic foraminifera, shell-bearing protists, are familiar from geological studies. Although many species are well known, undescribed single-chambered forms are common in the deep sea. Coastal and sublittoral species often have restricted distributions, but wide ranges are more frequent among deep-water species, particularly at abyssal depths. This probably reflects the transport of tiny propagules by currents across ocean basins that present few insurmountable barriers to dispersal, combined with slow rates of evolution. Undersampling of the vast deep-sea habitat, however, makes it very difficult to establish the ranges of less common foraminiferal species, and endemism may be more prevalent than currently realized. On continental slopes, some species have restricted distributions, but wide-ranging bathyal species that exhibit considerable morphological variation are more common. This may be linked to the greater heterogeneity of continental slopes compared with oceans basins. Improved knowledge of deep-sea foraminiferal biogeography requires sound morphology-based taxonomy combined with molecular genetic studies.

Controls on ostracod valve geochemistry, Part 1: Variations of environmental parameters in ostracod (micro-)habitats

The variations of environmental conditions ( T°, pH, δ 13C DIC, [DIC], δ 18O, Mg/Ca, and Sr/Ca) of ostracod habitats were examined to determine the controls of environmental parameters on the chemical and isotopic composition of ostracod valves. Results of a one-year monitoring of environmental parameters at five sites, with depths of between 2 and 70 m, in Lake Geneva indicate that in littoral to sub-littoral zones (2, 5, and 13 m), the chemical composition of bottom water varies seasonally in concert with changes in temperature and photosynthetic activity. An increase of temperature and photosynthetic activity leads to an increase in δ 13C values of DIC and to precipitation of authigenic calcite, which results in a concomitant increase of Mg/Ca and Sr/Ca ratios of water. In deeper sites (33 and 70 m), the composition of bottom water remains constant throughout the year and isotopic values and trace element contents are similar to those of deep water within the lake. The chemical composition of interstitial pore water also does not reflect seasonal variations but is controlled by calcite dissolution, aerobic respiration, anaerobic respiration with reduction of sulphate and/or nitrate, and methanogenesis that may occur in the sediment pores. Relative influence of each of these factors on the pore water geochemistry depends on sediment thickness and texture, oxygen content in bottom as well as pore water. Variations of chemical compositions of the ostracod valves of this study vary according to the specific ecology of the ostracod species analysed, that is its life-cycle and its (micro-)habitat. Littoral species have compositions that are related to the seasonal variations of temperature, δ 13C values of DIC, and of Mg/Ca and Sr/Ca ratios of water. In contrast, the compositions of profundal species are largely controlled by variations of pore fluids along sediment depth profiles according to the specific depth preference of the species. The control on the geochemistry of sub-littoral species is a combination of controls for the littoral and profundal species as well as the specific ecology of the species.

Elucidating Marine Biogeography with Macrophytes: Quantitative Analysis of the North Atlantic Supports the Thermogeographic Model and Demonstrates a Distinct Subarctic Region in the Northwestern Atlantic

Quantitative analysis of North Atlantic macrophyte (seaweed) abundance was used to test the thermogeographic model (TM) of marine biogeography. The TM uses coastal area and seawater temperature over Pleistocene time to reveal long-term climate/ area clusters that predict biogeographic regions. An earlier study with the TM predicted 20 of 24 classical biogeographic regions; the 4 omitted regions were either weak, disputed, or structurally (sandy/silty regions) inapplicable to the TM. The TM predicted a new western North Atlantic Subarctic Region, centered on the Strait of Belle Isle and lying between Newfoundland and Labrador. In contrast, Nova Scotia and the Gulf of Maine were found to be a Boreal/Subarctic transition zone. The predictions of the TM were earlier supported with coralline algal abundances, and here are supported by a test with macrophyte assemblages.Seaweed assemblages were studied at 51 primary SCUBA stations with 4–7 standard depth zones at each station from southern Labrador to Cape Elizabeth, ME. Meter-square quadrats were taken at each station, followed by at-sea sorting, identification, and weighing of biomass by species. A permanent record of these studies is provided by archived underwater photography and voucher herbarium samples, including tissue in silica gel to support future DNA analyses. Comparisons of European seaweed assemblages were accomplished by re-analyzing semi-quantitative data available in the literature.We demonstrate with the biomass data that a 3000-km stretch of coast (i.e., northern Gulf of St. Lawrence, northeastern Newfoundland, and southern Labrador) that is centered on the Strait of Belle Isle has a unique assemblage of seaweeds. In its location and marine climate, this coast closely matches the Subarctic Region predicted by the TM. Based on graphic demonstration, this Subarctic Region is radically different from that of Nova Scotia and the Gulf of Maine, and its dominant species derive from the North Pacific Ocean. Several different statistical approaches applied to the macrophyte data demonstrate the strength of these findings, while also finding that a subset of Subarctic species persists in deeper water to the south in the transition zone (i.e., southwestern Nova Scotia, Gulf of Maine). Only a very small proportion of the seaweed flora of the Subarctic Region is Arctic in origin (<4%). Earlier geographic analyses of biodiversity did not discover the Subarctic Region because rare species hide the strength of assemblages based on abundance.Many of the dominant seaweeds in the transitional region of the Gulf of Maine and Nova Scotia occur widely in Europe, and are Boreal in origin. Such Boreal species form 47–80% of the macrophyte biomass at depths shallower than 5 m in the northwestern Atlantic transition zone southwest of the Subarctic Region. In deeper water (>5 m), however, European Boreal species are only 22–25% of the macrophyte biomass. Although many of the dominant, shallow sublittoral species of the European Boreal flora have made the North Atlantic passage, only about 10% (by biomass) of mid-depth species (2.5–5 m) have crossed and even fewer of the deeper European species are found in the northwestern Atlantic. A few European “Boreal” seaweeds reach further north into the Subarctic Region, but only at low levels of biomass and primarily at mid-depths (2.5–5 m). The Subarctic is inhospitable for establishment of such species in shallow water because of low winter temperatures and sea ice, and in deeper water by low summer temperatures (<5 °C).Few ecologists have had the opportunity to work in the Subarctic Region; instead, most of the recent descriptive and experimental studies of northwestern Atlantic ecosystems are based on studies in the smaller transition zone in the Gulf of Maine and southwestern Nova Scotia. Consequently, we provide detailed photographic, tabular, and graphic descriptions of the seaweed assemblages within the Subarctic and their interactions with

Morpho-functional patterns and zonation of South Chilean seaweeds: the importance of photosynthetic and bio-optical traits

We address the question of whether seaweed zonation can be characterized in terms of light absorption, pigmentation, photosynthetic parameters, photoinhibition, and thallus structure. Based on 32 seaweed species from the Pacific coast of southern Chile, intertidal assemblages exhib- ited higher light requirements for photosynthesis (Ek) and lower thallus light absorptances than sub- tidal algae. Ek values were lower than the highest measured irradiances at the corresponding natural depths, suggesting that photosynthesis in these organisms could potentially occur at lower depths. During summer, 1% of photosynthetically active radiation (PAR) reached a depth of 23 m, while UV- B and UV-A wavelengths were completely attenuated at <3 and 6 m, respectively. Overall, the pho- tobiological adaptations were associated with depth, morphology, and taxonomic group. Photoinhibi- tion was similar in algae from different depths, although recovery was higher in upper littoral algae than in infra- and sublittoral species. The characteristics conferring competitive abilities in light use and light stress tolerance were not, or only partially, related to the classical Littler form-function model. The filamentous and foliose forms were able to acclimate rapidly to changing light and phys- ical stress in the supralittoral zone. For infralittoral kelps living in a highly dynamic environment, higher cross-sectional area and enhanced in vivo light absorption were coupled with morphological features (e.g. massive thallus) that are advantageous in withstanding e.g. water movement. By con- trast, the rapid physiological adjustments that allow algae to endure solar stress (e.g. photochemical down-regulation) were strongly dependent on the position on the shore but not on gross morphology.

The Living Columbariinae (Gastropoda: Neogastropoda: Turbinellidae) of New Zealand

The Columbariinae have been represented in the fauna of New Zealand from the Paleocene until the Recent, providing the longest known continuous record for the subfamily. Seven living species, representing the genera Columbarium, Coluzea, and Fulgurofusus, are recognized, and include two species, Fulgurofusus maxwelli and Fulgurofusus marshalli that are described as new. The New Zealand columbariine fauna is unusually diverse at the generic level, and includes the largest members of the subfamily, as well as the only primarily sublittoral species. The morphology, anatomy, and distribution of the living species are discussed, as are their relationships to living and fossil congeners.