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91.
Morphometric and meristic characteristics of a specimen of Grammicolepis brachiusculus Poey caught off the Algarve coast, southern Portugal, are reported. This is the first record of this benthopelagic species in Portuguese waters (including Madeira and Azores Archipelagos) and its fifth finding in the north-eastern Atlantic.  相似文献   
92.
Two marine urostylid ciliates, Holosticha hamulata n. sp. and Holosticha heterofoissneri Hu and Song, 2001, were investigated using live observation and protargol impregnation. Both species were isolated from Korean intertidal sediments of the Yellow Sea. Holosticha hamulata measures about 150 x 25 mum in vivo, and is characterized by a tripartite body shape with a narrow head, an inflated trunk, and a tail that distally projects ventrally forming a hook-like structure. It is the characteristic body shape that distinguishes H. hamulata distinctly from congeners. Holosticha hamulata differs from H. heterofoissneri, possibly the nearest relative, also by the location of the contractile vacuole (ahead of mid-body versus near posterior body third) and the configuration of the macronucleus (on average, 33 scattered nodules assuming a Y-shape versus 17 nodules that may form a U shape). The average number of the macronuclear nodules is a pronounced feature showing great consistency in populations of each species. However, their arrangement is variable in H. heterofoissneri where the nodules are basically scattered or connected by fine fibers forming an elongate U-shape. The location of the contractile vacuole as a taxonomic feature is discussed and a dichotomous key to the species of Holosticha sensu stricto is provided.  相似文献   
93.
Prolonged swimming capacity (critical swimming speed, U crit, protocol) and metabolism were measured for 14 Atlantic cod Gadus morhua exposed to seven oxygen levels within the non-lethal range normally encountered in the Gulf of St Lawrence (35 to 100% saturation). Burst-and-coast swimming was triggered earlier (at lower speeds) in hypoxia, and burst-and-coast movements were more frequent in hypoxia than in normoxia at low speeds. Furthermore, the metabolic scope beyond the metabolic rate at which Atlantic cod resorted to burst-and-coast movements decreased gradually as ambient oxygen concentration dropped. Overall, fewer burst-and-coast movements were observed in hypoxia while the distance swum in burst-and-coast mode remained c . 1% of the total distance swam in all tests. Oxygen availability had no effect on the rate of increase in metabolic rate with increasing velocity <50 cm s−1, but limited swimming performances and metabolic rate at higher speeds. The prevailing low oxygen tensions on the bottom in the deep channels may impair the swimming capacity of Atlantic cod in the estuary and northern Gulf of St Lawrence.  相似文献   
94.
Little is known about the ecology and behavior of southern Australian bottlenose dolphins (Tursiops sp.). This hinders assessment of their conservation status and informed decision‐making concerning their management. We used boat‐based surveys and photo‐identification data to investigate site fidelity, residency patterns, and the abundance of southern Australian bottlenose dolphins in Adelaide's coastal waters. Sighting rates and site fidelity varied amongst individuals, and agglomerative hierarchical cluster analysis led to the categorization of individuals into one of three groups: occasional visitors, seasonal residents, or year‐round residents. Lagged identification rates indicated that these dolphins used the study area regularly from year to year following a model of emigration and reimmigration. Abundance estimates obtained from multisample closed capture‐recapture models ranged from 95 individuals (SE ± 45.20) in winter 2013 to 239 (SE ± 54.91) in summer 2014. The varying levels of site fidelity and residency, and the relatively high number of dolphins found throughout the study area highlights the Adelaide metropolitan coast as an important habitat for bottlenose dolphins. As these dolphins also appear to spend considerable time outside the study area, future research, conservation, and management efforts on this population must take into account anthropogenic activities within Adelaide's coastal waters and their adjacencies.  相似文献   
95.
96.
The surveillance of marine mammal strandings within the framework of a biomonitoring scheme for the Mauritanian coast led to the discovery in 2013 of a 3.98?m long, juvenile rorqual Balaenoptera sp. in an advanced state of decomposition near Chott Boul (16°32.488′N, 016°27.0317′W). Photographs and skin samples were taken, but the specimen could not be collected. Based on limited morphological evidence, only Balaenoptera edeni and B. omurai were plausible. Sequences of three mtDNA regions, i.e. parts of the cox1 and the cytb genes as well as the D-loop, for a total of 2636?bp (> 16% of the mitogenome) identified the specimen as an Omura's whale, B. omurai, the first record in the Atlantic Ocean and at least 11,400?km away from its closest known range in the SW Indian Ocean (Madagascar). The question of whether the specimen is a vagrant or belongs to an unrecognized Atlantic population is discussed. Advection by currents or transport on a ship's bow bulb following collision are discarded. Circumstances (juvenile status, great distance from Indo-Pacific, necessary inter-oceanic passage through cold temperate waters) may slightly favour the hypothesis that B. omurai, if rare, could be autochthonous in the Atlantic. Beach surveys remain a useful tool to assess trends in cetacean species composition, to detect unusual mortality events and to help assess the impacts of anthropogenic activities. This is particularly applicable to remote areas where the marine mammal fauna is poorly known and where fisheries effort is high, such as the Mauritanian coast.  相似文献   
97.
Based on the diagnostic morphological characters of the Arundo taxa, and after both field and herbarium observation, three species (A. micrantha, A. plinii and A. donax) were found along the eastern Adriatic coast. Altogether, 50 phytocoenological relevés from Arundo stands were collected in Croatia, Montenegro and Albania between 2010 and 2013. Three associations with a predominance of Arundo species were determined: Arundinetum plinianae, Arundinetum micranthae and Arundini donacis–Convolvuletum sepium. Among them, Arundinetum micranthae is described and proposed as a new association, belonging to the Artemisietea vulgaris class. It occurs frequently along the coastal belt between the cities of Split and Dubrovnik in South Croatia. The syntaxonomy of the associations is discussed and comparison with similar communities from Italy is made. The vegetation and floristic structure of the associations is discussed as a potential basis for biodiversity conservation programmes and for evaluating the state of these ecosystems in the future.  相似文献   
98.
99.
Pinewoods are distinctive environmental elements in the Mediterranean coastal area and have both natural and historical significance. From the evening of March 4th to the morning of March 5th, 2015, a severe and unusual windstorm occurred in the Tuscany region of central Italy with wind gusts over 120 km/h. The windstorm caused vast damage to the anthropic and natural environment and wounded numerous trees in the renowned pinewoods of Parco della Versiliana in the Tyrrhenian coastal area. The meteorological calamity provided the opportunity to i) date the onset of the artificial plantation of the present Italian stone pine (Pinus pinea L.) forest to the 1820s, ii) build a long-term tree-ring chronology of the Italian stone pines in the area and iii) analyze the climate-growth relationship of the Italian stone pine in the study area. The resulting Versiliana chronology was derived from 60 trees and spanned from 1828 to 2014 (187 years), representing one of the longest living Italian stone pine forests on the Italian Peninsula. Finally, the climate-growth analysis highlighted that at this site the latewood width is positively influenced by summer temperature, a peculiarity worthy of further investigations.  相似文献   
100.
Nina Furnari 《Mammal Review》2013,43(4):323-326
Cavia intermedia, a rare species of cavy found exclusively on Moleques do Sul Island, Brazil, differs from other cavies in genetic and morphological characteristics and has been regarded as phylogenetically closest to Cavia magna. Here, I present morphological evidence for the likely origin of Cavia intermedia from an ancestor shared with Cavia magna: an external female genital organ similar in size and appearance to the male's penis. Masculinization of the female genitalia has been observed in Cavia magna but does not occur in Cavia aperea, which suggests a sister relationship between Cavia magna and Cavia intermedia.  相似文献   
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