Spermatozoa and phylogenesis of the pectinid bivalve Flexopecten glaber

2006 ◽  
Vol 86 (2) ◽  
pp. 425-428 ◽  
Author(s):  
Gaël Le Pennec ◽  
Nejla Aloui-Bejaoui ◽  
Marcel Le Pennec
Keyword(s):  
The Other ◽  
Ultrastructural Characteristics ◽  
The Mediterranean ◽  
Dense Chromatin ◽  
Mature Spermatozoa

Gonad of the Mediterranean pectinid Flexopecten glaber was studied in order to describe the morphology and the ultrastructural characteristics of the mature spermatozoa. The spermatozoon has a 2.5 μm pyriform head and a 40–45 μm flagellum. The four mitochondria of the mid-piece are 0.6 μm in diameter. The nucleus contains dense chromatin fibres and possesses two depressions: a wide (0.19 μm) and deep (0.58 μm) sub-acrosomal one, and the other at the base of the head, less deep (0.36 μm) and less wide (0.12 μm). The objective was to situate this scallop in the phylogenetic diagrams found in the literature concerning the commercial pectinid species.

The butterfly squid Stoloteuthis leucoptera in the Mediterranean

1991 ◽  
Vol 71 (1) ◽  
pp. 47-51 ◽  
Author(s):  
Lidia Orsi Relini ◽  
Daniela Massi
Keyword(s):  
Life Cycle ◽  
Adult Male ◽  
The Other ◽  
Otter Trawl ◽  
Ligurian Sea ◽  
The Mediterranean ◽  
Unique Species ◽  
Recent Immigration

The presence of Stoloteuthis leucoptera in the Mediterranean is recorded on the basis of three specimens, including an adult male, caught by IKMT and by commercial otter-trawl in the Ligurian Sea. The hypothesis of a recent immigration is discussed.The list of Mediterranean cephalopods (Mangold Wirz, 1963; Torchio, 1968; Bello, 1986; Mangold & Boletzsky, 1987) includes the Sepiolidae of the subfamily Heteroteuthinae, whose members are supposed to be pelagic throughout their life cycle. Mangold Wirz (1963) recognizes in the Mediterranean fauna the unique species Heteroteuthis dispar, the other authors include H. atlantis Voss, which Voss himself (1955) reported at Messina. To this group may now be added Stoloteuthis leucoptera (Verrill, 1878) a species until now recorded in limited Atlantic areas. Verrill (1881) wrote “This species is an exceedingly beautiful one, when living, owing to the elegance and brilliancy of its colours and the gracefulness of its movements. In swimming it moves its fins in a manner analogous to the motion of the wings of a butterfly.”

The Agreement between Greece and Italy on the Delimitation of their Respective Maritime Zones: An Italian Perspective

2021 ◽  
Vol 30 (1) ◽  
pp. 283-294
Author(s):  
Marina Mancini
Keyword(s):  
Continental Shelf ◽  
International Law ◽  
The Other ◽  
Boundary Line ◽  
Great Success ◽  
Ionian Sea ◽  
National Interests ◽  
The Mediterranean

In 2020 Greece and Italy concluded a maritime delimitation agreement, extending the already-established boundary line between their respective continental shelf areas to the other maritime areas to which they are entitled under international law. The Greek authorities hailed the agreement as a great success, stressing that it fully reflects their position vis-à-vis maritime delimitation in the Mediterranean and it meets their national interests in the Ionian Sea. This article critically analyzes the agreement, in the light of various recent events, and it finds that it serves Italian interests too. In particular, the 2020 Italo-Greek agreement furthers Italy’s growing interest in delimiting the maritime zones to which it is entitled under international law, so as to prevent its rights and jurisdiction over them being impaired by the proclamation of overlapping zones by its neighbours. It also sets the stage for future proclamation by Italy of an EEZ covering the waters adjacent to its territorial sea in the Ionian Sea.

scholarly journals Applicability of the Decision Matrix of North Eastern Atlantic, Mediterranean and connected seas Tsunami Warning System to the Italian tsunamis

2012 ◽  
Vol 12 (3) ◽  
pp. 843-857 ◽  
Author(s):  
S. Tinti ◽  
L. Graziani ◽  
B. Brizuela ◽  
A. Maramai ◽  
S. Gallazzi
Keyword(s):  
Indian Ocean ◽  
Warning System ◽  
Tsunami Warning ◽  
The Other ◽  
Tsunami Source ◽  
Indian Ocean Tsunami ◽  
Decision Matrix ◽  
Tsunami Warning System ◽  
North Eastern ◽  
The Mediterranean

Abstract. After the 2004 Indian Ocean tsunami catastrophe, UNESCO through the IOC (Intergovernmental Oceanographic Commission) sponsored the establishment of Intergovernmental Coordination Groups (ICG) with the aim to devise and implement Tsunami Warning Systems (TWSs) in all the oceans exposed to tsunamis, in addition to the one already in operation in the Pacific (PTWS). In this context, since 2005, efforts have begun for the establishment of TWSs in the Indian Ocean (IOTWS), in the Caribbean area (CARIBE EWS) and in the North Eastern Atlantic, the Mediterranean and Connected Seas (NEAMTWS). In this paper, we focus on a specific tool that was first introduced in the PTWS routine operations, i.e., the Decision Matrix (DM). This is an easy-to-use table establishing a link between the main parameters of an earthquake and the possible ensuing tsunami in order to make quick decision on the type of alert bulletins that a Tsunami Warning Center launches to its recipients. In the process of implementation of a regional TWS for the NEAM area, two distinct DMs were recently proposed by the ICG/NEAMTWS, one for the Atlantic and the other for the entire Mediterranean area. This work applies the Mediterranean NEAMTWS DM to the earthquakes recorded in Italy and compares the action predicted by the DM vs. the action that should be appropriate in view of the observed tsunami characteristics with the aim to establish how good the performance of the Italian TWS will be when it uses the DM for future events. To this purpose, we make use of the parametric catalogue of the Italian earthquakes (CPTI04) compiled in 2004 and the most recent compilation of the Italian tsunami, based on the Italian Tsunami Catalogue of 2004 and the subsequent revisions. In order to better compare the TWS actions, we have identified four different kinds of action coding them from 0 to 3 according to the tsunami severity and have further considered three different distance ranges where these actions apply, that is local, regional and basin-wide, that refer to the distance of the message recipients from the tsunami source. The result of our analysis is that the actions prescribed by the DM are adequate only in 45%–55% of the cases, overestimations are about 37% and underestimations are the rest. As a whole, the predictive ability of the DM is not satisfactory, which implies that recipients have the difficult task in managing bulletins carrying a great deal of uncertainty and on the other hand also suggests that strategies to improve the DM or to go beyond the DM need to be found.

scholarly journals Serial nominations for the AWH initiative: The paradigm of seven-stone antas and beyond

2015 ◽  
Vol 11 (A29A) ◽  
pp. 102-104
Author(s):  
Juan Antonio Belmonte ◽  
César González García ◽  
Michael Hoskin
Keyword(s):  
Iberian Peninsula ◽  
World Heritage ◽  
The Other ◽  
Short Report ◽  
Excellent Candidate ◽  
The Mediterranean ◽  
The Ideal

AbstractIn this short report we examine the ideal status of the seven-stone antas (a type of very ancient megalithic monument in the southwest of the Iberian Peninsula) as an excellent candidate for a serial nomination within the Astronomy and World Heritage Initiative. This case will be compared with an extraordinary set of dolmens at the other side of the Mediterranean, within the Transjordan Plateau, worthy of being protected under the umbrella of the same initiative but which are in serious danger of ‘extinction’.

scholarly journals First record of Solea (Microchirus) boscanion (Osteichthyes: Soleidae) in the Mediterranean Sea, with data on other sympatric soleid species

2002 ◽  
Vol 82 (5) ◽  
pp. 907-911 ◽  
Author(s):  
Enric Massutí ◽  
J.A. Reina-Hervás ◽  
Domingo Lloris ◽  
L. Gil de Sola
Keyword(s):  
Climate Change ◽  
Mediterranean Sea ◽  
First Record ◽  
Western Mediterranean ◽  
The Other ◽  
The Mediterranean

The capture of five specimens of Solea (Microchirus) boscanion (Osteichthyes: Soleidae), a species previously unrecorded in the Mediterranean, is reported from the Iberian coast (western Mediterranean). The main morphometric and meristic measurements of this species with data of the other sympatric, and morphologically very similar, soleids Microchirus variegatus and Buglossidium luteum are also given. The record is discussed in relation to climate change and competition between species.

Ultrastructural Characteristics of Capillaries Entering and Leaving the Stria Vascularis

1986 ◽  
Vol 95 (3) ◽  
pp. 309-312 ◽  
Author(s):  
Kensuke Watanabe
Keyword(s):  
Horseradish Peroxidase ◽  
Basal Cell ◽  
Stria Vascularis ◽  
The Other ◽  
Spiral Ligament ◽  
Perivascular Spaces ◽  
Basal Cells ◽  
Vascular Flow ◽  
Cell Layers ◽  
Ultrastructural Characteristics

Capillaries entering and leaving the stria vascularis were surrounded by layers of basal cells and fibrocytes. The entering capillaries were surrounded by one or two thin basal cells, while the leaving capillaries were surrounded by four or five thicker and interdigitated basal cell layers. Moreover, the layers surrounding the leaving capillaries persisted further into the spiral ligament. Two kinds of filaments were observed in the basal cells, one thin and the other thick. Capillaries were observed to leak horseradish peroxidase before they entered and after they left the stria vascularis. Although the reaction product of horseradish peroxidase was observed in all perivascular spaces of leaving capillaries, very little or no reaction product was observed around some entering capillaries. It is speculated that the layers of basal cells and fibrocytes around entering and leaving capillaries control the vascular flow out of the stria vascularis, although the layers around leaving capillaries may be more contractile than those around entering capillaries.

scholarly journals XX. Discovery of the metamorphosis in the second type of the cirripedes, viz. the lepades, completing the natural history of these singular animals, and confirming their affinity with the crustacea

1835 ◽  
Vol 125 ◽  
pp. 355-358 ◽  
Keyword(s):  
North America ◽  
Natural History ◽  
Sea Water ◽  
The Other ◽  
External Appearance ◽  
The Real ◽  
Real Nature ◽  
History Of ◽  
The Mediterranean ◽  
The Waves

The Fourth Memoir, published in my Zoological Researches and Illustrations, No. III. page 69, &c., having first made known the real nature of the Cirripedes , the key of which remained concealed in their metamorphosis, it might have been expected that some naturalist favourably situated to investigate the oceanic tribe of these animals, would have been the first to make the same discovery in regard to these, and thereby complete their natural history. It was scarcely to be expected that the honour of this discovery also should be reserved for the author, fixed to one spot, where none of them naturally exist, and are but casually thrown upon our shores by the waves of the Atlantic, attached to pieces of wreck, or brought into port fixed to the bottoms of ships returning from distant voyages. Fortunately, however, two ships of this description came into this harbour (Cork), one from the Mediterranean, the other from North America, which, not being sheathed with copper, had their bot­toms literally covered with Barnacles of the three genera of Lepas , Cineras , and Otion ; and having persons employed expressly for the purpose, numbers of these were brought alive in sea water, amongst which were many with the ova in various stages of their progress, and some ready to hatch, which they eventually did in prodigious numbers, so as to enable him to add the proof of their being, like the Balani, natatory Crusta­cea in their first stage , but of a totally different facies and structure; a circumstance which determines the propriety of the separation of the Cirripedes into two tribes, and evinces the sagacity of Mr. MacLeay in being the first to indicate that these two tribes, the Balani and Lepades , were not so closely related as generally supposed. The larvæ of the Balani , described in Memoir IV. under the external appearance of the bivalve Monoculi ( Astracoda ), have a pair of pedunculated eyes, more numerous and more completely developed members, approximating to those of Cyclops , and of the perfect Triton ; while, in the present type, or Lepades , the larva resembles some­what that of the Cyclops , which Müller, mistaking for a perfect animal, named Amymone , and which can be shown to he common to a great many of the Entomostraca ; or the resemblance is still more striking to that of the Argulus Armiger of Latreille, which, in fact, is but an Amymone furnished with a tricuspidate shield at the back.

scholarly journals A Key for Determining the African Species of Anopheles (Sensu Lato)

1912 ◽  
Vol 3 (3) ◽  
pp. 241-250 ◽  
Author(s):  
F. W. Edwards
Keyword(s):  
Mediterranean Region ◽  
New Records ◽  
British Museum ◽  
The Other ◽  
Reasonable Doubt ◽  
Close Connection ◽  
African Species ◽  
Other Hand ◽  
Specific Rank ◽  
The Mediterranean

The compilation of the following key has been a matter of no little difficulty, mainly owing to the close connection of the species in some of the groups, which sometimes makes it almost impossible to assign specific limits. The difficulty has in some cases been increased through the paucity of material, which prevents any adequate conception of the range of variability being obtained. This is particularly the case with some of the species coming from the Mediterranean region, which are very closely allied, and of which, as a rule, the British Museum possesses very few specimens. Names have only been sunk here as synonyms in those cases where there appeared to be no reasonable doubt, either after a comparison of the types, or of the descriptions, when these were sufficiently detailed. Eventually, therefore, it may be found that some forms which are here given specific rank will have to be regarded at most as varieties. Since so many figures of Anopheline wings, etc., have already appeared, it is not deemed necessary to add to their number. Some new records have been included, but on the other hand some old ones, which appeared to be questionable, have been omitted. As with the writer's previous papers, this key is merely intended to supplement the detailed descriptions which will be found in other works.

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