The extinct catshark Pachyscyllium distans (PROBST, 1879) (Elasmobranchii: Carcharhiniformes) in the Pliocene of the Mediterranean Sea

Sharks assigned to the carcharhiniform family Scyliorhinidae account for about 160 extant species placed in 18 genera. Most living scyliorhinids are small- to medium- sized ground sharks provided with cat- like eyes and nasal barbels similar to whiskers; hence their vernacular name, "cat- sharks". Living catsharks mostly inhabit deep or rather deep waters of the warm and temperate seas worldwide, foraging on small fishes and inverterbates. In the present paper, we report on a lateral tooth of Scyliorhinidae collected from a clay pit at Certaldo (central Italy), where marine mudstones belonging to the famously fossiliferous Pliocene successions of Tuscany are exposed. This catshark specimen represents the second bona fide record of the extinct premontreine species Pachyscyllium distans in the Pliocene of the Mediterranean Sea, as well as the geologically youngest confirmed occurrence of this species worldwide. In the Mediterranean Pliocene, P. distans thus coexisted with the similar but distinct species Pachyscyllium dachiardii. After having been widespread in Northern Atlantic, Paratethyan, and Mediterranean waters in Miocene times, P. distans became confined to the Mediterranean Sea during the Pliocene. Therefore, similar to what has recently been suggested for P. dachiardii, we hypothesise that the range of P. distans contracted southward as colder conditions took hold in the Northern Hemisphere. The eventual extinction of P. distans might be related to the first cooling episode that significantly affected the Mediterranean biota around 3 Ma.

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Links of the significant wave height distribution in the Mediterranean sea with the Northern Hemisphere teleconnection patterns

Advances in Geosciences ◽

10.5194/adgeo-17-13-2008 ◽

2008 ◽

Vol 17 ◽

pp. 13-18 ◽

Cited By ~ 16

Author(s):

P. Lionello ◽

M. B. Galati

Keyword(s):

Mediterranean Sea ◽

Northern Hemisphere ◽

Wave Height ◽

Significant Wave Height ◽

Height Distribution ◽

East Atlantic ◽

Significant Wave ◽

Teleconnection Patterns ◽

Wave Height Distribution ◽

The Mediterranean

Abstract. This study analyzes the link between the SWH (Significant Wave Height) distribution in the Mediterranean Sea during the second half of the 20th century and the Northern Hemisphere SLP (Sea Level Pressure) teleconnection patterns. The SWH distribution is computed using the WAM (WAve Model) forced by the surface wind fields provided by the ERA-40 reanalysis for the period 1958–2001. The time series of mid-latitude teleconnection patterns are downloaded from the NOAA web site. This study shows that several mid-latitude patterns are linked to the SWH field in the Mediterranean, especially in its western part during the cold season: East Atlantic Pattern (EA), Scandinavian Pattern (SCA), North Atlantic Oscillation (NAO), East Atlantic/West Russia Pattern (EA/WR) and East Pacific/ North Pacific Pattern (EP/NP). Though the East Atlantic pattern exerts the largest influence, it is not sufficient to characterize the dominant variability. NAO, though relevant, has an effect smaller than EA and comparable to other patterns. Some link results from possibly spurious structures. Patterns which have a very different global structure are associated to similar spatial features of the wave variability in the Mediterranean Sea. These two problems are, admittedly, shortcomings of this analysis, which shows the complexity of the response of the Mediterranean SWH to global scale SLP teleconnection patterns.

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Mercury speciation in surface and deep waters of the Mediterranean Sea

Marine Chemistry ◽

10.1016/j.marchem.2007.02.012 ◽

2007 ◽

Vol 107 (1) ◽

pp. 13-30 ◽

Cited By ~ 82

Author(s):

Jože Kotnik ◽

Milena Horvat ◽

Emmanuel Tessier ◽

Nives Ogrinc ◽

Mathilde Monperrus ◽

...

Keyword(s):

Mediterranean Sea ◽

Mercury Speciation ◽

Deep Waters ◽

The Mediterranean

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Hydrogen peroxide in deep waters from the Mediterranean Sea, South Atlantic and South Pacific Oceans

Scientific Reports ◽

10.1038/srep43436 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 15

Author(s):

Mark J. Hopwood ◽

Insa Rapp ◽

Christian Schlosser ◽

Eric P. Achterberg

Keyword(s):

Hydrogen Peroxide ◽

Mediterranean Sea ◽

South Pacific ◽

South Atlantic ◽

Deep Waters ◽

The Mediterranean

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Distributions of the carbonate system properties, anthropogenic CO<sub>2</sub>, and acidification during the 2008 BOUM cruise (Mediterranean Sea)

Biogeosciences Discussions ◽

10.5194/bgd-9-2709-2012 ◽

2012 ◽

Vol 9 (3) ◽

pp. 2709-2753 ◽

Cited By ~ 17

Author(s):

F. Touratier ◽

V. Guglielmi ◽

C. Goyet ◽

L. Prieur ◽

M. Pujo-Pay ◽

...

Keyword(s):

Mediterranean Sea ◽

Dissolved Inorganic Carbon ◽

Marine Ecosystem ◽

Total Alkalinity ◽

Carbonate System ◽

Simple Method ◽

Deep Waters ◽

History Of ◽

The Mediterranean ◽

System Properties

Abstract. We relate here the distributions of two carbonate system key properties (total alkalinity, AT; and total dissolved inorganic carbon, CT) measured along a section in the Mediterranean Sea, going from Marseille (France) to the south of the Cyprus Island, during the 2008 BOUM cruise. The three main objectives of the present study are (1) to draw and comment on the distributions of AT and CT in the light of others properties like salinity, temperature, and dissolved oxygen, (2) to estimate the distribution of the anthropogenic CO2 (CANT) in the intermediate and the deep waters, and (3) to calculate the resulting variation of pH (acidification) since the beginning of the industrial era. Since the calculation of CANT is always an intense subject of debate, we apply two radically different approaches to estimate CANT: the very simple method TrOCA and the MIX approach, the latter being more precise but also more difficult to apply. A clear picture for the AT and the CT distributions is obtained: the mean concentration of AT is higher in the oriental basin while that of CT is higher in the occidental basin of the Mediterranean Sea, fully coherent with the previous published works. Despite of the two very different approaches we use here (TrOCA and MIX), the estimated distributions of CANT are very similar. These distributions show that the minimum of CANT encountered during the BOUM cruise is higher than 46.3 μmol kg−1 (TrOCA) or 48.8 μmol kg−1(MIX). All Mediterranean water masses (even the deepest) appear to be highly contaminated by CANT, as a result of the very intense advective processes that characterize the recent history of the Mediterranean circulation. As a consequence, unprecedented levels of acidification are reached with an estimated decrease of pH since the pre-industrial era of −0.148 to −0.061 pH unit, which places the Mediterranean Sea as one of the most acidified world marine ecosystem.

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Did titanic stingrays wander the Pliocene Mediterranean Sea? Some notes on a giant-sized myliobatoid stinger from the Piacenzian of Italy

Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen ◽

10.1127/njgpa/2020/0941 ◽

2020 ◽

Vol 298 (2) ◽

pp. 155-164

Author(s):

Alberto Collareta ◽

Marco Merella ◽

Simone Casati ◽

Andrea Di Cencio

Keyword(s):

Mediterranean Sea ◽

Central Italy ◽

Shallow Marine ◽

Marine Deposits ◽

The Family ◽

Freshwater Stingray ◽

Living Species ◽

The Mediterranean

A fossil caudal spine of a stingray (Elasmobranchii: Batomorphii: Myliobatoidei) is here reported from upper Pliocene (Piacenzian) shallow-marine deposits exposed at the La Serra locality of Tuscany (central Italy). In spite of being incomplete, this specimen displays an amazing maximum preserved anteroposterior length of 420 mm, which to our knowledge makes it the longest stingray stinger ever reported from both the fossil and the Recent records. Tentatively referred to the family Dasyatidae, the herein described fossil appears to be more than twice as long as the longest caudal spines reported from any living myliobatoid species of the Mediterranean Sea. Therefore, it represents a stingray taxon that is no longer featured in the present-day Mediterranean ray assemblage, and as such, it expands our knowledge on the Pliocene biodiversity of the Mediterranean Sea. Given that the living species Bathytoshia brevicaudata (the smooth stingray) and Urogymnus polylepis (the giant freshwater stingray), while displaying the greatest values of total stinger length (up to c. 375 mm in the latter) among extant myliobatoids, are also known as the largest living species of stingrays besides Mobulidae, it seems much reasonable to hypothesise that the caudal spine from La Serra belonged to a very large- sized stingray individual which would have been larger than (or at least comparable in dimensions to) the largest members of the titan-sized B. brevicaudata and U. polylepis .

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Assessment of the influence of material glaciation in the Northern Hemisphere on the processes of water desalination in the Mediterranean Sea in the Pliocene-Pleistocene

Hydrosphere Еcology (Экология гидросферы) ◽

10.33624/2587-9367-2019-2(4)-1-7 ◽

2019 ◽

pp. 1-7

Author(s):

Nikolay V. Esin ◽

Nikolay I. Esin ◽

Igor S. Podymov ◽

Anna V. Lifanchuk ◽

Irina V. Melnikova

Keyword(s):

Mediterranean Sea ◽

Sea Level ◽

Northern Hemisphere ◽

Black Sea ◽

Water Desalination ◽

The Black Sea ◽

Geological Data ◽

Ocean Water ◽

The Mediterranean ◽

Freshwater Balance

The article calculates the freshwater balance of the ancient Black and Caspian seas and estimates the volume of water flowing from the Black Sea to the Mediterranean during the melting of glaciers. It is shown that during this period up to 855 km3/year of freshwater is discharged into the Mediterranean Sea, which is involved in the formation of sea level. A comparison of calculations and geological data showed that there are no signs of the influx of salty ocean water into the Akchagyl Sea. It was also shown that water from the ocean cannot flow up since the sea level was below sea level.

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The zoogeography of extant rhabdopleurid hemichordates (Pterobranchia : Graptolithina), with a new species from the Mediterranean Sea

Invertebrate Systematics ◽

10.1071/is17021 ◽

2018 ◽

Vol 32 (1) ◽

pp. 100 ◽

Cited By ~ 5

Author(s):

Elena Beli ◽

Giorgio Aglieri ◽

Francesca Strano ◽

Davide Maggioni ◽

Max J. Telford ◽

...

Keyword(s):

New Species ◽

Mediterranean Sea ◽

Phylogenetic Analyses ◽

Depth Range ◽

Extant Species ◽

Evolutionary Radiation ◽

Early Origin ◽

The Mediterranean ◽

A New Species ◽

Cephalic Shield

The early origin and evolutionary radiation of graptolites (Hemichordata:Pterobranchia) is a story told almost entirely in the fossil record, but for four extant species of the genus Rhabdopleura Allman, 1869. Here we report the discovery of a fifth species, Rhabdopleura recondita, sp. nov., at a depth range of 2–70m from the Adriatic and Ionian Seas, always associated with bryozoans in coralligenous habitats. This is the first pterobranch record in Italian waters, and the second in the Mediterranean Sea. The new species is characterised by: (1) tubaria with smooth creeping tubes adherent to the inside of empty bryozoan zooecia; (2) erect outer tubes with a graptolite, fusellar-like organisation; and (3) zooids that extend from a black stolon, which is free from the creeping tube. Each of the paired feeding arms has two rows of tentacles that do not extend to the arm tip. The distal ends of the arms, the collar and the cephalic shield are replete with black granules. Phylogenetic analyses of individual and concatenated gene sequences of mitochondrial 16S rDNA and nuclear 18S rDNA support the validity of R. recondita as a new species. Finally, we discuss the global biogeographic and habitat distributions of the extant Rhabdopleura representatives. http://zoobank.org/urn:lsid:zoobank.org:pub:82C6A51E-F8F4-44AF-AD8F-16873BE80D03

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