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1.
A crab previously unknown in the European fauna was discovered in La Rochelle (France) in 1994. This shore crab was identified as Hemigrapsus penicillatus, a North-West Pacific species. It appears to be spreading rapidly. It has now been detected from Laredo, Spain (43 °25′N, 03 °20′W) to Fromentine, France (46°53′N, 02°09′W) in sheltered areas of the mid-littoral zone. It is locally abundant, with a density of up to 10–20 individuals per square metre. In its native area, its distribution ranges from a cold (northern Japan, south of the Pacific coast of Russia) to a tropical (Taiwan, Hong-Kong) habitat. Being tolerant to both high and low temperatures (even at freezing point), it will probably colonize most of the European and North-African coasts within a short period of time.  相似文献   

2.
With the increase in global oceanic trade the establishment of non-indigenous marine organisms has become a major environmental and economic problem worldwide. Recently, the Atlantic rock crab (Cancer irroratus) was reported in Icelandic waters, Eastern North Atlantic. This is the first record of this relatively large crab species outside its natural range, i.e. the east coast of North America. The crab was most likely transferred to Iceland as larvae in ballast water and has successfully established a reproducing population in Icelandic waters. The species is distributed along the southwestern- and western-coast of Iceland. Adult specimens are now common in Faxaflói Bay, Southwest Iceland, but with sporadic occurrences in western and northwestern Icelandic waters. The green crab (Carcinus maenas) and the spider crab (Hyas araneus) are the only native brachyuran decapod species commonly found in its new habitat, but despite its recent colonization the rock crab was the most abundant brachyuran in the areas studied in southwest Iceland. Egg bearing rock crab and green crab females were found from June to October, while egg bearing spider crab females were seen from July to December. In Southwest Iceland both rock crab and green crab larvae were abundant in mid-summer but rare in both spring and autumn, which is opposite of what was observed for the spider crab. The size and abundance of adult crabs, their reproductive conditions, and occurrence of all larval stages, indicate that the Atlantic rock crab has successfully colonized Iceland.  相似文献   

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More than 1,000 non-indigenous aquatic species have been recorded, in total, from coastal Europe, i.e. navigational inland waterways for ocean-going vessels and adjacent water bodies in close proximity. Regions considered in this overview range from European Arctic waters to the Mediterranean Sea and Irish waters to the Black Sea. The majority of introduced taxa have been first recorded since the 1950s. Approximately 600 taxa (ranging from unicellular algae to vertebrates) are established with self-sustaining populations. The dominating group of exotic species across all seas is zoobenthos organisms. Introduction vectors are predominantly shipping (ballast water and hull fouling) and species movements for aquaculture or stocking purposes.  相似文献   

5.
The hermit crab Pagurus parvispina Komai, 1997 (Decapoda: Paguridae) was found in Vostok Bay (Peter the Great Bay, Sea of Japan) at a depth of 50?C65 m. Earlier, this species was recorded from the type locality in northern Japan at a depth of 150?C200 m. The finding of P. parvispina in Vostok Bay is its first record in Russian waters and substantially expands the distribution area of this species in the Sea of Japan. Discorsopagurus maclaughlinae Komai, 1995 inhabits Russian waters and was earlier identified as Orthopagurus schmitti (Stevens, 1925); its taxonomical position is discussed.  相似文献   

6.
The paper discusses the first record of the association between the medusa Lychnoriza lucerna Haeckel, 1880 and the decapod Libinia spinosa Milne-Edwards, 1934 in neritic waters of Argentina. Our results allow us to conclude that the symbiotic relation between these two species is a common phenomenon. The crab L. spinosa is located in the subgenital pockets of L. lucerna such that one-half of its cephalothorax is exposed to the outside. The crabs feed at the expense of the medusa, ingesting some portion of its food. A few specimens of the crab have been found, mostly females; the only male was of a somewhat larger size.  相似文献   

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The Japanese shore crab that occurs along the mainland Russian coast of the Sea of Japan, which was formerly defined as Hemigrapsus penicillatus (de Haan, 1835), should be attributed as Hemigrapsus takanoi Asakura et Watanabe, 2005. This conclusion is based on the study of material from the Peter the Great Bay. We discuss the range and ecology of both species.  相似文献   

10.
Limnoperna fortunei (Bivalvia, Mitylidae) was introduced into South America in 1991 in the La Plata River (Argentina). It arrived in the ballast water of ships coming from Asia, where this species is native. It was first observed in 1998 in the Paraguay River. Limnoperna was introduced into the Pantanal region as hull fouling of vessels using the Paraguay–Parana waterway. This study describes how L. fortunei came to the Pantanal region, and provides details of its occurrence, density, and impacts. From 1999 to 2002, observations and sampling on natural and artificial substrates in the Paraguay River were made. Some aspects of the spread and impacts, based on local community information, were also analyzed. On artificial substrate the density reached 523.8 individuals m−2 and on natural substrate (rocks), up to 10,000 individuals m−2 were found. The densities observed were quite low compared to those found in Southern Brazil, where values up to 100,000 individuals m−2 have been recorded in the last 3 years. In the Paraguay River, the population density of L. fortunei can be negatively impacted by periodic low levels of dissolved oxygen and decreases in pH to between 5 and 6. Such conditions are frequently present during the periodic flooding or inundation of this area. Under these conditions, a high mortality of L. fortunei was recorded in March of 2002, on both natural and artificial substrates. Despite low densities, L. fortunei can colonize water cooling systems of boats, obstructing water circulation and causing motor overheating. Accumulation in water supply equipment, such as pumps and pipes has also been observed. An erratum to this article is available at .  相似文献   

11.
A survey of species belonging to the family Mysidae, conducted in June 2007 in fresh- to brackish waters of eastern France, revealed a recent range extension of the invasive Ponto-Caspian species Hemimysis anomala to the Moselle, Saône, and Rhône rivers. In the estuary of the Grand Rhône it reached for the first time the Mediterranean coast. The network of navigation canals in NE France was likely a key element of its north to south pathway starting from the Rhine River. Important range extensions were also noted for Limnomysis benedeni in this network and in the Moselle River. The euryhaline species Neomysis integer, endemic in coastal waters of the NE Atlantic, was found in the Rhône delta, thus confirming previous very rare records in the 1930–1950s from the Mediterranean coast of France. Invasion mechanisms and pathways, expansion potential, and establishment conditions of the species are discussed.  相似文献   

12.
Ocean acidification, a decrease in the pH in marine waters associated with rising atmospheric CO2 levels, is a serious threat to marine ecosystems. In this paper, we determine the effects of long-term exposure to near-future levels of ocean acidification on the growth, condition, calcification, and survival of juvenile red king crabs, Paralithodes camtschaticus, and Tanner crabs, Chionoecetes bairdi. Juveniles were reared in individual containers for nearly 200 days in flowing control (pH 8.0), pH 7.8, and pH 7.5 seawater at ambient temperatures (range 4.4–11.9 °C). In both species, survival decreased with pH, with 100% mortality of red king crabs occurring after 95 days in pH 7.5 water. Though the morphology of neither species was affected by acidification, both species grew slower in acidified water. At the end of the experiment, calcium concentration was measured in each crab and the dry mass and condition index of each crab were determined. Ocean acidification did not affect the calcium content of red king crab but did decrease the condition index, while it had the opposite effect on Tanner crabs, decreasing calcium content but leaving the condition index unchanged. This suggests that red king crab may be able to maintain calcification rates, but at a high energetic cost. The decrease in survival and growth of each species is likely to have a serious negative effect on their populations in the absence of evolutionary adaptation or acclimatization over the coming decades.  相似文献   

13.
Aim This paper evaluates global collection records, evidence of anthropogenic transport methods, and experimental and distributional data relative to temperature requirements to understand the historical and potential dispersal of a well‐known genus of estuarine crab. Location The records analysed are from temperate and tropical coastal ocean areas. Methods The study is based primarily on literature analysis and examination of museum specimens. Results The human‐mediated successful global dispersal of the European shore crabs Carcinus maenas (Linnaeus, 1758) and C. aestuarii (Nardo, 1847) occurred in three major episodes: around 1800, in the 1850s–70s, and in the 1980s–90s. The nineteenth century introductions occurred through transport by ships (probably in hull fouling or in solid ballast), while the introductions in the 1980s could have occurred through a greater variety of dispersal mechanisms (ships’ hull fouling and seawater system fouling; fouling on semisubmersible drilling platforms; ballast water; transport with fisheries products intended for food or bait; scientific research; releases from aquaria maintained for educational or scientific purposes; or intentional non‐governmental releases for human food production). These introductions have resulted in Carcinus’ establishment in five temperate regions outside of its native Europe in Atlantic North America, Australia, South Africa, Japan and Pacific North America, while releases into tropical regions have not established populations. C. maenas’ range in both its native and introduced regions appears to be regulated by similar temperature parameters, enabling an assessment of its potential distribution. Main conclusions The second episode of Carcinus’ global dispersal, the period from the 1850s to 1870s, may be part of a broader surge of world‐wide invasions caused by an increase in shipping.  相似文献   

14.
Large native geographical range and number of introduction events are often invoked to explain the successful establishment of alien mammal species. To infer the native geographic range of the Siberian chipmunks Tamias (Eutamias) sibiricus (Lax.) invasion in France, we identified the subspecies that individuals sampled in 5 out of the 11 established populations belonged. Based on craniometrical measures, variation in the mtDNA sequence of the cytochrome b, and alarm call sonogram shape, all French specimens were members of T. (E.) s. barberi which has the smallest geographical range (Korean peninsula) of the three recognized subspecies. An intense pet trade between European countries and Korea until the 1980’s best explains the success in establishment of this small ground-squirrel in France, where it was released mainly by private owners. Size of the native geographical range should be interpreted with caution in explaining the establishment of an invasive species, at least without a precise knowledge of its introduction pathways and taxonomic status.  相似文献   

15.
Several specimens of the genus Ascocystites (Blastozoa, Eocrinoidea) are described for the first time in Late Ordovician deposits (Bou M’Haoud Formation) from the Ougarta Range, Algeria. This genus was previously known in Darriwilian–Sandbian deposits of four other areas of the Mediterranean Province (Czech Republic, France, Morocco and Portugal). The Algerian material completes its palaeobiogeographic distribution in the peri-Gondwanan area, restricted in shallow water settings.  相似文献   

16.
The occurrence of Archaeopsittacus sp. (Psittaciformes) in the fossil deposits of Sansan (France) is reported, testifying to a survival of this genus in the Middle Miocene, as Archaeopsittacus verreauxi was described from the Early Miocene of Saint-Gérand-le-Puy (France) and was recorded only from its type locality. The data discussed here indicate the presence of two parrot species from Sansan, as it is the type locality of another parrot species, Pararallus dispar, only known from this locality. The differences between the humeri of these two taxa are described in detail, together with the differences from the other European fossil parrot species. The presence of more than one species of parrot in the same locality is not rare, but in Europe it is recorded in Sansan for the second time. Evidence for parrots also confirms the paleoenvironmental reconstruction of Sansan, as parrots are primarily arboreal species. Archaeopsittacus also represents one of the few common elements between the Early and Middle Miocene European bird assemblages.  相似文献   

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Two specimens of Valenciennea helsdingenii (Bleeker, 1858) were collected off Punnakayal coast, from Gulf of Mannar, southeast coast of India in November 2012. The morphometric and meristic characters of the recorded specimens are described and discussed. This is the first record of the species from the Indian waters that is a range extension of its known range within the Indian Ocean.  相似文献   

19.
《Comptes Rendus Palevol》2013,12(4):191-202
We describe here “miacid” taxa from the Early Eocene Paris Basin locality of Le Quesnoy (Oise, France). We describe the new species Vassacyon taxidiotis, the first European record of this genus. The other “miacids” identified from Le Quesnoy are Miacis latouri and Gracilocyon solei. The P4 of G. solei is described here for the first time. Its morphology (e.g., wide protocone, short postmetacrista) supports a close relationship with Miacis rundlei from Abbey Wood (MP8 + 9, England). The latter species is therefore classified as Gracilocyon rundlei. Three new tooth positions are known for Miacis latouri: P4, p4 and m2. They support its reference to Miacis. These specimens imply that the European species is more basal than the North American species. The fauna from Le Quesnoy shares with Dormaal the presence of Miacis latouri and Gracilocyon solei, but the “miacid” fauna from Le Quesnoy also contains Vassacyon taxidiotis. The presence in Le Quesnoy of the two former taxa supports a reference to MP7 level of the French locality. The presence of three distinct genera in European localities show that the “Miacidae” were diversified in Europe, as previously observed in North America. The genera Gracilocyon, Miacis, and Vassacyon probably dispersed from Europe to North America during the Palaeocene/Eocene boundary.  相似文献   

20.
A symbiotic crab Sestrostoma balssi (Shen, 1932) (Varunidae: Gaeticinae) that lives in burrows of the large ghost shrimp Upogebia major (De Haan, 1841) and U. issaeffi (Balss, 1913) (Upogebiidae) was found in Vostok Bay (Peter the Great Bay, Sea of Japan) for the first time. The occurrence of mature and juvenile specimens indicates the existence of a stable population of this species in the investigated region. This finding substantially extends the distribution area of S. balssi in the Sea of Japan.  相似文献   

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