scholarly journals New Miocene Monachinae from the Western Shore of the Chesapeake Bay (Maryland, USA)

2017 ◽  
Vol 51 (3) ◽  
pp. 221-242 ◽  
Author(s):  
S. J. Rahmat ◽  
I. A. Koretsky ◽  
J. E. Osborne ◽  
A. A. Alford

Abstract The Family Phocidae includes four subfamilies (Phocinae, Monachinae, Cystophorinae, and Devinophocinae) consisting of mediumto large-sized mammals that possess distinctive adaptations to semi-aquatic life. In the Miocene of the Chesapeake Group, only two subfamilies of the Family Phocidae were identified: Phocinae and Monachinae. Leptophoca, a representative of the subfamily Phocinae, appears on the eastern shore of the North Atlantic around 16 million years ago. Recently, two new monachine species, the larger Terranectes magnus (n. gen., n. sp.) and the medium-sized T. parvus (n. sp.), were recorded in the Upper Miocene of the Chesapeake Group in the Eastover Formation (7.0–6.0 Ma) and St. Marys Formation (10.0-8.0 Ma). These two distinct subfamilies of seals indicate a well-marked divergence between phocines and monachines, much earlier than 18 million years ago, as previously suggested. The Eastover Formation was deposited in a shallow embayment that covered southern Maryland, the coastal plain of Virginia, and the northeastern corner of North Carolina. The geologically older St. Marys Formation represents a tide-influenced coastal environment, with low-salinity estuaries. There was a sharp temperature decrease in the Late Miocene, indicated by a shift to a cooler-water fish fauna during St. Marys time. The Eastover Formation reflects warmer waters with relatively strong currents, significant shoals, barriers, and varied depths. Fossil evidence of earlier seals suggests that phocids originated in the North Atlantic and otarioids in the North Pacific. True seals diverged from ancient Carnivora in the early Oligocene (or earlier) in the Paratethyan / Mediterranean Basins, spread widely during the Middle Miocene and crossed westward across the Atlantic Ocean, before dispersing in the eastern United States by the Early Pliocene.

1960 ◽  
Vol 14 (1) ◽  
pp. 37-59 ◽  
Author(s):  
Ernst B. Haas ◽  
Peter H. Merkl

Western European Union (WEU) is unique in the family of European organizations. Its membership comprises Great Britain in addition to the inner circle of the six nations of Little Europe. As such it was hailed as a big step forward from the continental limitations of European integration. Its special task, besides residuary powers in the cultural, social, and economic field, has been defense and the control of armaments. Western European Union was erected on the ruins of the European Defense Community (EDC) by the Paris Agreements of October 1954. Its legal basis was the Brussels Treaty Organization of 1948, a defensive alliance against future German aggression which over the years had left its military functions to the North Atlantic Treaty Organization (NATO) and had concentrated on its cultural and social role.


Author(s):  
A. Sabatés ◽  
M. Demestre ◽  
P. Sanchez

The study of the morphological and meristic characters of larval and adult sandeels (Gymnammodytes spp.) collected off the Catalan coast (NW Mediterranean) has revealed the co-occurrence of G. cicerelus and G. semisquamatus in the Mediterranean. The geo-graphical distribution of G. semisquamatus had hitherto been thought to be limited to the European Atlantic coasts. The comparative analysis of specimens of G. semisquamatus from the Mediterranean and from the North Atlantic has demonstrated a marked latitudinal cline in the meristic counts. An exhaustive overview is presented of the bibliography referring to the Ammodytidae family in the Mediterranean, and the validity of the numerous references is discussed. Finally, it has been shown that the accepted description of G. cicerelus included the two species: G. cicerelus and G. semisquamatus. In the present paper an up-to-date diagnosis of both species is presented.


2021 ◽  
Author(s):  
Sylvia Stinnett ◽  
Joshua Durkee ◽  
Joshua Gilliland ◽  
Victoria Murley ◽  
Alan Black ◽  
...  

<p>The North Atlantic Oscillation (NAO) is a high-frequency oscillation that has known influences on the climatology of weather patterns across the eastern United States. This study explores the relationship between the daily North Atlantic Oscillation index with observed high-wind events from 391 first-order weather stations across the eastern U.S. from 1973-2015. These events were determined following typical National Weather Service high-wind criteria: sustained winds of at least 18 m•s-1 for at least 1 hour or a wind gust of at least 26 m•s-1 for any duration. Since research literature shows high-wind events are often connected to parent mid-latitude cyclone tracks, and since the NAO has been shown to influence these storm tracks, it is hypothesized that changes in NAO phases are connected to spatial shifts and frequencies in high-wind observations. Initial results show a preferred southwesterly direction during each NAO phase. Variance in high-wind directions appears to increase (decrease) during negative (positive) NAO phases. Further, the greatest spatial difference in the mean center of high-wind observations was between positive and negative NAO phases. Overall, these preliminary findings indicate changes in high-wind observations may be linked to NAO phases.</p>


Author(s):  
Eve C. Southward

Collections of bottom-living animals from the continental slope of the northern Bay of Biscay contain a new species of Oligobrachia; this increases the number of species of Oligobrachia known from the North Atlantic to five. Oligobrachiids are quite frequently found incubating embryos and five individuals of the new species carry embryos. Oligobrachia embryos have been studied morphologically already (Ivanov, 1957, 1975; Southward & Southward, 1963; Brattegard, 1966; Ivanov & Gureeva, 1976) and should prove useful material for experimental studies in future. Incubation is also known in the family Siboglinidae, but neither embryos nor larvae have been seen in any other pogonophoran families. The Biscay collections also contain additional specimens of Oligobrachia ivanovi and these have been useful in revising the description of this rather rare species.


2020 ◽  
Vol 222 (2) ◽  
pp. 1339-1351 ◽  
Author(s):  
Lise Retailleau ◽  
Pierre Boué ◽  
Lei Li ◽  
Michel Campillo

SUMMARY Body waves can be extracted from correlation functions computed from seismic records even at teleseismic distances. Here we use P and PcP waves from the secondary microseism frequency band that are propagating between Europe and the Eastern United States to image the core–mantle boundary (CMB) and D” structure beneath the North Atlantic. This study presents the first 3-D image of the lower mantle obtained from ocean-generated microseism data. Robustness of our results is evaluated by comparing images produced by propagation in both directions. Our observations reveal complex patterns of lateral and vertical variations of P-wave reflectivity with a particularly strong anomaly extending upward in the lower mantle up to 2600 km deep. We compare these results with synthetic data and associate this anomaly to a Vp velocity increase above the CMB. Our image aims at promoting the study of the lower mantle with microseism noise excitations.


2007 ◽  
Vol 7 (1) ◽  
pp. 39-42 ◽  
Author(s):  
Alexandra Elaine Rizzo ◽  
Antonia Cecília Zacagnini Amaral

Paralacydoniid polychaetes belonging to the genus Paralacydonia Fauvel 1913 were collected during the REVIZEE Program/South Score/Benthos ("Avaliação do Potencial Sustentável dos Recursos Vivos na Zona Econômica Exclusiva") on the outer shelf and continental slope off the south-southeastern coast of Brazil between 156 and 400 m depth. This new report extends the known geographic distribution of the family, which had previously been recorded in the North Atlantic as far as the Gulf of Mexico. Paralacydonia is here treated as monotypic; P. mortenseni Augener 1924 and P. weberi Horst 1923 are considered synonyms of Paralacydonia paradoxa Fauvel 1913.


2001 ◽  
Vol 79 (12) ◽  
pp. 2280-2288 ◽  
Author(s):  
Chad L Hewitt ◽  
Jeffrey HR Goddard

A new species of hydroid, Candelabrum fritchmanii, is described from Cape Arago, Oregon, U.S.A. Specimens were collected from the intertidal region underneath boulders. This new species' standing with respect to other members of the genus is discussed. The claspers in the blastostylar region of the new species show similarities to the North Atlantic Candelabrum cocksii. However, three specimens had multiple, connected polyps at varying stages of development and the cnidome differs between C. cocksii and the new species, leading to the erection of a new species. The polyp cnidome consists of desmonemes, heteronemes (microbasic mastigophores and homotrichous microbasic euryteles), and stenoteles and the actinula cnidome consists of desmonemes, haplonemes (atrichous isorhizas), and stenoteles. Emendations to the family, subfamily, and genus diagnoses are presented to accommodate these findings. Observations are also presented on actinula development and the ensnaring, predatory feeding behavior of the highly contractile polyp.


2011 ◽  
Vol 41 (9) ◽  
pp. 1630-1638 ◽  
Author(s):  
Ayan H. Chaudhuri ◽  
Avijit Gangopadhyay ◽  
James J. Bisagni

Abstract Regional observational studies in the North Atlantic have noted significant hydrographical shifts in 1997–98 because of the episodic drop in the North Atlantic oscillation (NAO) during 1996. Investigation using a basin-scale model finds that, although the western North Atlantic (WNA) witnessed unusually low-salinity water by 1997, the eastern North Atlantic (ENA) simultaneously evidenced intrusions of high-salinity water at intermediate depths. This study shows that a major source of high salinity in the ENA is from the northward penetration of Mediterranean Outflow Water (MOW) that occurred concurrently with a westward shift of the subpolar front. The authors confirm that the low-salinity intrusion in the WNA is from enhanced Labrador Current flow. Results from climatological high- and low-NAO simulations suggest that the NAO-induced circulation changes that occurred in 1997–98 are a characteristic North Atlantic basin response to different forcing conditions during characteristic high- and low-NAO periods.


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