Heydrichia (?) poignantii, sp nov (Sporolithaceae, Sporolithales, Rhodophyta), a 100 million year old fossil coralline red alga from north-eastern Brazil, and a new Hauterivian record of Sporolithon from Switzerland

Fossil specimens of Heydrichia (?) poignantii, sp. nov. (Sporolithaceae, Sporolithales, Rhodophyta), representing the first confirmation of the genus in the fossil record, were discovered in thin sections of Albian limestones from the Riachuelo Formation, Sergipe Basin, and in thin sections of Albian -Cenomanian limestones from the Ponta do Mel Formation, Potiguar Basin in north-eastern Brazil. A detailed morphological-anatomical account of the species is provided, and its placement in Heydrichia is discussed in relation to current classification proposals. Comparisons with the four other known species of the genus, all non-fossil, show that H. poignantii is the only known species of Heydrichia in which thalli are encrusting to sparsely warty to horizontally layered with overlapping lamellate branches that commonly appear variously curved or arched, and in which thalli have sporangial complexes that become buried in the thallus. The evolutionary history of Heydrichia remains uncertain, but available data suggest that the genus may have diverged from the sporolithacean genus Sporolithon, known as early as Hauterivian times (c. 129.4-132.9 +/- 1 Ma) from Spain (and newly reported here from Switzerland), or it may have arisen from a graticulacean alga such as Graticula, dating from mid-Silurian times (c. 427-435 Ma). Current data also suggest that Heydrichia is more likely to have arrived in Brazil from Central Atlantic waters than from higher latitude South Atlantic waters. This implies that currently living species in southern Africa probably arose later from ancestors further equatorward in the South Atlantic, although confirming studies are needed. All non-fossil species of Heydrichia are known only from the southern hemisphere.

An integrated stratigraphic record of the Palaeocene-lower Eocene at Gubbio (Italy): new insights into the early Palaeogene hyperthermals and carbon isotope excursions

Terra Nova, 24, 380386, 2012 Abstract A high-resolution, integrated stratigraphic framework (stable isotope stratigraphy, standard calcareous nannofossil and foraminiferal biostratigraphy, magnetostratigraphy) together with geochemical and rock magnetic properties analyses of a complete and well-preserved succession at Contessa Valley (Gubbio, central Italy) have offered an excellent opportunity to identify and constrain the Palaeocene to early Eocene hyperthermals and carbon isotope excursions (CIEs). In addition, we provide the first evidence in the Tethys Ocean of CIEs, previously identified in the Pacific, Atlantic and Southern Oceans, highlighting their global significance and of some unknown CIEs. Their characteristics are compared with those reported for deep-sea cores and other land-based sections to test whether the signature associated with CIEs documented in our composite section might give evidence for tracing them over wider areas. The Contessa composite section thus represents a reference succession also for insight into the magnetobiochronostratigraphy and the magnitude of early Palaeogene hyperthermals and CIEs.

First record of the genus Ruffojassa Vader & Myers, 1996 (Amphipoda, Corophiidea) from Brazilian waters, with description of a new species

A new species, Ruffojassa petronioi sp. nov., is described from southern Brazilian coast. The new species was collected at 56 m depth at the coordinates 21º42'S / 40º15'W with a mini biological trawl aboard of R.V. Prof.W.Besnard. In this paper we recorded the genus for the first time from Brazilian waters.

New data on the Lateglacial period of SW Europe: a high resolution multiproxy record from Laguna de la Roya (NW Iberia)

High-resolution multiproxy analyses were performed on a 128 cm section of organic sediments accumulated in a small mountain lake in NW Iberia (Laguna de la Roya, 1608 m asl). The pollen stratigraphy together with radiocarbon dating provided the basis for a chronology ranging from 15,600 to 10,500 cal yr BP. Chironomid-inferred July air temperatures suggest a temperature range from 7 to 13 degrees C, also evidencing two well-established cold periods which may be equivalent to the INTIMATE stages GS-2a and GS-1. Furthermore, a number of short cold events (with summer temperatures dropping about 0.5-1 degrees C) appear intercalated within the Lateglacial Interstadial (possibly equivalent to the INTIMATE cold events GI-1d, GI-1c2 and GI-1b) and the early Holocene (possibly equivalent to the 11.2 k event). The temperature variations predicted by our reconstruction allow explaining the changes in local conditions and productivity of the lake inferred from the biological record of the same sediment core. Furthermore, they also agree with the local and regional vegetation dynamics, and the main oscillations deduced for the vegetation belts. Based on its chronology our multiproxy record indicates a similar temperature development in NW Iberia as inferred by the Greenland delta O-18 record, the marine deep-sea records off the Atlantic Iberian Margin, and other chironomid-based Lateglacial temperature reconstructions from Europe. Nevertheless, the impact of most of the less intense Lateglacial/early Holocene cold events in NW Iberia was most probably limited to very sensitive sites that were very close to ecotonal situations. Particularly, our new pollen record indicates that they were represented as three minor environmental crises occurring during the Lateglacial Interestadial in this area. The Older Dryas event (in our usage corresponding to the Aegelsee Oscillation in Central Europe and event GI-1d in central Greenland) has previously been described in this region, but its age and duration (ca 14,250-14050 cal yr BP) is now better constrained. The two subsequent stages, La Roya I (ca 13,600-13,400 cal yr BP) and La Roya II (ca 13,300-12,900 cal yr BP) have been described for first time in NW Iberia. (C) 2013 Elsevier Ltd. All rights reserved.

A new modern analogue reference dataset and its application to the 430-kyr pollen record from Lake Biwa

This study presents a newly compiled dataset of modern pollen and climate data from 798 sites across Japan and the Russian Far East. This comprehensive reference dataset combined with the modern analogue technique (MAT) provides a powerful tool for pollen-based reconstruction of the Quaternary Northwest Pacific climate. Pollen-derived reconstruction of the modern climate at the reference pollen-sampling sites matches well with the estimated modern climate values (R2 values vary between 0.79 and 0.95, and RMSEP values vary between 5.8 and 9.7% of the modern climatic range for all nine tested variables). The successful testing of the method encourages its application to the fossil pollen records. We used a coarse-resolution pollen record from Lake Biwa to reconstruct glacial-interglacial climate dynamics in central Japan since ~438 kyr and compared it to the earlier reconstruction based on a less representative reference dataset. The current and earlier results consistently demonstrate that the coldest glacial intervals experienced pronounced cooling in winter and moderate cooling in summer, supporting the growth of cool mixed forest (COMX) where warm mixed forest (WAMX) predominates today. During the last glacial, maximum (~24 kyr BP) mean temperatures of the coldest (MTCO) and warmest (MTWA) month were about -13 °C (RMSEP = 2.34 °C) and 21 °C (RMSEP = 1.66 °C) respectively, and annual precipitation (PANN) was about 800 mm (RMSEP = 158.06 mm). During the thermal optimums of the interglacial intervals, the temperatures of the coldest and warmest month were above 0 °C and 25 °C respectively, leading to the reconstruction of WAMX and temperate conifer forest (TECO). Although both these vegetation types grow in the southern part of Japan today, WAMX requires warmer space. The presence of WAMX during marine isotope stages (MIS) 11 and 1, and its absence during MIS 9 and MIS 5 contradict the marine isotope and Antarctic ice records, suggesting that the latter two interglacials were the warmest of the last 800 kyr. The apparent contradiction allows at least three different explanations including low temporal resolution of the pollen record; different trends in CO2 concentrations during 'short' and 'long' interglacials; and regional climate variability and non-linear response of different regions to the global forcing. More definitive conclusions will be possible on the basis of forthcoming high-resolution pollen records from central Japan.

Stable carbon and oxygen isotope record of diagenetic carbonates from the New Jersey shelf

Carbon cycling is an important but poorly understood process on passive continental margins. In this study, we use the ionic and stable isotopic composition of interstitial waters and the petrology, mineralogy, and stable isotopic composition of authigenic carbonates collected from Ocean Drilling Program (ODP) Leg 174A (Sites 1071 and 1072) to constrain the origin of the carbonates and the evolution of methane on the outer New Jersey shelf. The pore fluids of the New Jersey continental shelf are characterized by (1) a fresh-brackish water plume, and (2) organic matter degradation reactions, which proceed through sulfate reduction. However, only minor methanogenesis occurs. The oxygen isotopic composition of the pore fluids supports a meteoric origin of the low salinity fluids. Authigenic carbonates are found in nodules, thin (~1-cm) layers, and carbonate cemented pavements. Siderite is the most common authigenic carbonate, followed by dolomite and calcite. The oxygen isotopic composition of the authigenic carbonates, i.e. 1.3-6.5 per mil PeeDee Belemnite (PDB), indicates an origin in marine pore fluids. The carbon isotopic composition of dolomite cements range from -16.4 to -8.8 per mil PDB, consistent with formation within the zone of sulfate reduction. Siderite d13C values show a greater range (-17.67-16.4 per mil), but are largely positive (mean=2.8 per mil) and are interpreted to have formed throughout the zone of methanogenesis. In contrast, calcite d13C values are highly negative (as low as -41.7 per mil)and must have formed from waters with a large component of dissolved inorganic carbon derived from methane oxidation. Pore water data show that despite complete sulfate reduction, methanogenesis appears not to be an important process presently occurring in the upper 400 m of the outer New Jersey shelf. In contrast, the carbon isotopic composition of the siderites and calcites document an active methanogenic zone during their formation. The methane may have been either oxidized or vented from shelf sediments, perhaps during sea-level fluctuations. If this unaccounted and variable methane flux is an areally important process during Neogene sea-level fluctuations, then it likely plays an important role in long-term carbon cycling on passive continental margins

Late Quaternary benthic foraminiferal record of the Bounty Trough, east of New Zealand

The Bounty Trough, east of New Zealand, lies along the southeastern edge of the present-day Subtropical Front (STF), and is a major conduit via the Bounty Channel, for terrigenous sediment supply from the uplifted Southern Alps to the abyssal Bounty Fan. Census data on 65 benthic foraminiferal faunas (>63 µm) from upper bathyal (ODP 1119), lower bathyal (DSDP 594) and abyssal (ODP 1122) sequences, test and refine existing models for the paleoceanographic and sedimentary history of the trough through the last 150 ka (marine isotope stages, MIS 6-1). Cluster analysis allows recognition of six species groups, whose distribution patterns coincide with bathymetry, the climate cycles and displaced turbidite beds. Detrended canonical correspondence analysis and comparisons with modern faunal patterns suggest that the groups are most strongly influenced by food supply (organic carbon flux), and to a lesser extent by bottom water oxygen and factors relating to sediment type. Major faunal changes at upper bathyal depths (1119) probably resulted from cycles of counter-intuitive seaward-landward migrations of the Southland Front (SF) (north-south sector of the STF). Benthic foraminiferal changes suggest that lower nutrient, cool Subantarctic Surface Water (SAW) was overhead in warm intervals, and higher nutrient-bearing, warm neritic Subtropical Surface Water (STW) was overhead in cold intervals. At lower bathyal depths (594), foraminiferal changes indicate increased glacial productivity and lowered bottom oxygen, attributed to increased upwelling and inflow of cold, nutrient-rich, Antarctic Intermediate Water (AAIW) and shallowing of the oxygen-minimum zone (upper Circum Polar Deep Water, CPDW). The observed cyclical benthic foraminiferal changes are not a result of associations migrating up and down the slope, as glacial faunas (dominated by Globocassidulina canalisuturata and Eilohedra levicula at upper and lower bathyal depths, respectively) are markedly different from those currently living in the Bounty Trough. On the abyssal Bounty Fan (1122), faunal changes correlate most strongly with grain size, and are attributed to varying amounts of mixing of displaced and in-situ faunas. Most of the displaced foraminifera in turbiditic sand beds are sourced from mid-outer shelf depths at the head of the Bounty Channel. Turbidity currents were more prevalent during, but not restricted to, glacial intervals.

Stable carbon isotope record of benthic foraminifera across the Paleocene-Eocene thermal maximum in the New Jersey Coastal Plain

In the New Jersey Coastal Plain, a silty to clayey sedimentary unit (the Marlboro Formation) represents deposition during the Paleocene-Eocene thermal maximum (PETM). This interval is remarkably different from the glauconitic sands and silts of the underlying Paleocene Vincentown and overlying Eocene Manasquan Formation. We integrate new and published stable isotope, biostratigraphic, lithostratigraphic and ecostratigraphic records, constructing a detailed time frame for the PETM along a depth gradient at core sites Clayton, Wilson Lake, Ancora and Bass River (updip to downdip). The onset of the PETM, marked by the base of the carbon isotope excursion (CIE), is within the gradual transition from glauconitic silty sands to silty clay, and represented fully at the updip sites (Wilson Lake and Clayton). The CIE "core" interval is expanded at the updip sites, but truncated. The CIE "core" is complete at the Bass River and Ancora sites, where the early part of the recovery is present (most complete at Ancora). The extent to which the PETM is expressed in the sediments is highly variable between sites, with a significant unconformity at the base of the overlying lower Eocene sediments. Our regional correlation framework provides an improved age model, allowing better understanding of the progression of environmental changes during the PETM. High-resolution benthic foraminiferal data document the change from a sediment-starved shelf setting to a tropical, river-dominated mud-belt system during the PETM, probably due to intensification of the hydrologic cycle. The excellent preservation of foraminifera during the PETM and the lack of severe benthic extinction suggest there was no extreme ocean acidification in shelf settings.

Toward a new synthesis: Major evolutionary trends in the angiosperm fossil record

Angiosperm paleobotany has widened its horizons, incorporated new techniques, developed new databases, and accepted new questions that can now focus on the evolution of the group. The fossil record of early flowering plants is now playing an active role in addressing questions of angiosperm phylogeny, angiosperm origins, and angiosperm radiations. Three basic nodes of angiosperm radiations are identified: (i) the closed carpel and showy radially symmetrical flower, (ii) the bilateral flower, and (iii) fleshy fruits and nutritious nuts and seeds. These are all coevolutionary events and spread out through time during angiosperm evolution. The proposal is made that the genetics of the angiosperms pressured the evolution of the group toward reproductive systems that favored outcrossing. This resulted in the strongest selection in the angiosperms being directed toward the flower, fruits, and seeds. That is why these organs often provide the best systematic characters for the group.