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A medium-sized coffinfish, 183 mm total length and 170 g body weight, Chaunax pictus Lowe 1846, a species previously unrecorded in the Mediterranean Sea, has been trawled recently on deep-sea red shrimp grounds near the Sentinelle Bank (off the Algerian coast, central Mediterranean Sea).  相似文献   

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One specimen of the obtuse barracuda Sphyraena chrysotaenia is recorded for the first time from the Adriatic Sea.  相似文献   

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The black scabbardfish is a deep-sea teleost species with high commercial interest in the NE Atlantic. While it is caught by large offshore trawlers in the North of Europe, in the south it is captured by artisanal longlines. On the Portuguese continental slope, in the south of ICES Division IXa, a longline fleet has been engaged in the capture of black scabbardfish for more than 20 years. This paper reviews and analyses the features of this fishery from a temporal perspective based on information from different data sources. The fishery is based on the port of Sesimbra, where a family type fishing community strives to keep catches profitable without altering the artisanal features that characterizes the fleet. Although the fleet has experienced some technical improvements through time, the fishing operations and strategy have changed very little. Fishing occurs at particular areas on the slope, where individual vessels have their own fishing grounds. Annual landings surpassed 4,000 tonnes in the early 1990’s, but decreased to nearly 3,000 tonnes and have remained at this level since 2000. The length structure of the landings was stable from 2000 to 2005, with a modal (total length) class of 1,090 mm. Monthly landings per unit effort estimated by a generalized linear model did not present any marked trend for the period 2000–2004. The landings reported in mainland Portugal were compared with the ones from other regions of the ICES area and the different characteristics of the fisheries operating in the north and south of Europe were analysed.  相似文献   

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One male and four female Norway gobies Pomatoschistus norvegicus are reported from the Adriatic Sea.  相似文献   

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This paper reports quantitative, horizontal and vertical distributiondata of the 11 species of the family Xystonellidae found inthe Adriatic Sea and in the Strait of Otranto. The samples werecollected in coastal and open waters, with a plankton net equippedwith a closing system, in the period from 1973 to 1986. At thedeeper stations of the South Adriatic Pit, hauls were takenin eight vertical layers, while at other stations sampling dependedon the respective depth of each station. Xystonellidae are oceanictintinnines, mainly present in the South Adriatic and the Straitof Otranto throughout the year. They are characteristic of SouthAdriatic and Eastern Mediterranean water masses. Horizontaldistribution of lower mesopelagic species is limited by the200 m isobath. Only sparse individuals of the upper mesopelagicand epipelagic species were found in the Jabuka Pit, probablydue to the late autumn and winter current. These species werenot registered to the north of this region. They were registeredbelow the 200 m depth as dominant tintinnines, while in summerthey represented an average of 81% of the total tintinnine population.  相似文献   

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On 7 November and 15 December 2006, two specimens of the Lessepsian migrant Fistularia commersonni were caught in trammel nets off the coastal waters of Tricase Porto (southwestern Adriatic, Italy) and Sveti Andrija (southeastern Adriatic, Croatia), respectively. These represent the first records of this species in the Adriatic Sea.  相似文献   

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The occurrence of early stages (eggs) of scalloped ribbon fish,Zu cristatus, is reported for the first time in the Adriaticwaters. Four eggs with a diameter between 1.85 and 2.10 mm werefound in ichthyoplankton collections taken at Station 205, locationDue (43°25.8'N, 16°40.2'E, eastern central Adriatic).The capture of Z. cristatus in September is in agreement withthe proposedseasonal life cycle of species in the MediterraneanSea.  相似文献   

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The aim of the present study was to investigate the fisheries biology of Scomber japonicus (Houttuyn, 1782) in the Adriatic Sea, to enable implementation of appropriate regulatory measures for fisheries. Reproductive biology and sexual patterns of S. japonicus (chub mackerel) were examined from monthly random samples of commercial catches from purse seine nets (10 mm stretched mesh size) in the eastern Adriatic Sea. The annual mean chub mackerel fork length (FL) was examined from 1998 to 2007. Average fork lengths were approximately 25 cm between 1998 and 2002, decreasing to 22 cm between 2003 and 2007. In addition, sex ratios fluctuated as a function of size and month: females were more abundant in the smaller length classes, as well as before and after spawning; males were more abundant in the larger length classes and during spawning. The overall sex ratio was 0.68; females were significantly predominant. 50% of the chub mackerel population was sexually mature at a FL of 18.3 cm, and both males and females reached sexual maturity at FLs of 20.4 cm and 16.8 cm, respectively. Based on gonad maturity stages, gonad weight and gonadosomatic index, chub mackerel spawned from May to August, with peak spawning in June for both sexes. The mean absolute fecundity was 181 277 ± 62 090 oocytes per ovary. A positive exponential correlation was found between fecundity and fork length, gonad weight, and total chub mackerel weight (r2 = 0.640; r2 = 0.686 and r2 = 0.607, respectively).  相似文献   

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Reproductive aspects ofAlopias superciliosus in the northwestern Pacific were described in detail, on the basis of 629 specimens (429 females and 200 males) collected from January 1984 to October 1984 and from October 1992 to March 1994.Alopias superciliosus embryos are oophagous. Six developmental stages (3 encapsulative and 3 posthatching) based on embryonic morphology and source of nutrition were recognized. The species bears 2 embryos per litter, their size at birth being between 135 and 140 cm TL. The sex ratio of embryos was 1∶1. Total length of females at maturity was 332–341. 1. cm; of males 270.1–287.6 cm. The gestation period could not be determined because most adult females were pregnant throughout the year. The typical reproductive strategy ofA. superciliosus is the production of a few large embryos per litter, with no fixed mating or birthing season.  相似文献   

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Phyllobothrium squali Yamaguti, 1952 is redescribed and illustrated on the basis of the holotype from Squalus acanthias from Japanese waters and specimens from the same host off the Bulgarian Black Sea coast (new geographical record). The species is characterised by: a scolex diameter of 2.9-4.3 mm, a glandular apical organ, foliose bothridia with folded and posteriorly bifid margins, accessory suckers of 286-367 micro m in diameter, 222-373 testes per proglottis, an oval cirrus-sac with a length of 354-655 micro m, the vagina opening anteriorly to the cirrus-sac, and the terminal part of vagina with a circular musculature. Specimens from Etmopterus spinax off Naples, Mediterranean Sea, recorded by Euzet (1959) as Crossobothrium squali, are redescribed and their identification not confirmed. P. squali is recognised as a specific parasite of S. acanthias; it is presently known only from Japanese waters, the Black Sea and the Irish Sea. Changes to the generic diagnosis of Phyllobothrium, as given by Ruhnke (1996a), are proposed in order to include the characters of P. squali.  相似文献   

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The collection of a single specimen of the Guinean puffer Sphoeroides marmoratus from the Ionian Sea in September 1977, misidentified at that time as Lagocephalus lagocephalus , shows that this subtropical species of fish has occurred in the Mediterranean Sea from 30 years ago.  相似文献   

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