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A specimen of the filefish,Pervagor nigrolineatus, was collected from dead coral patches at a depth of 3 m in Zamami-jima, Kerama Islands (26° 14′ N, 127° 19′ E). This species is recorded for the first time from Japan. It has been known to be distributed in the tropical western Pacific from the Philippines to New Guinea (Hutchins, 1986). The present specimen is more similar in scale characters to the Philippine specimens than to the New Guinean ones.  相似文献   

3.
Nezumia liolepis and Nezumia stelgidolepis were collected during a National Marine Fisheries Service 1997 groundfish survey along the Pacific coast of North America. Bottom trawling was conducted from 188 to 1260 m depths. Nezumia liolepis were collected from 581 to 1247 m (3·4–5·7°C) and N. stelgidolepis from 285 to 555 m (6·0–8·4°C). The two species had distinct depth and temperature distributions and the majority of the specimens for each species came from narrow depth ranges. Nezumia stelgidolepis attains a larger pre-anal fin length (117 mm) than N. liolepis (83 mm), and age estimates from otolith ring counts indicate ages from 3 to 9 years for N. liolepis and 7 and 13 years for N. stelgidolepis from specimens collected. The gonads of N. liolepis were not reproductively active, and a single N. stelgidolepis possessed eggs of various sizes suggesting batch spawning. N. liolepis and N. stelgidolepis fed benthically, primarily on crustaceans such as amphipods, shrimp, mysids and polychaete worms. Although diet overlap was high, these two species appear to limit competition for resources by habitat separation.  相似文献   

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Diversity and abundance of benthic macrofauna associated to Thalassia testudinum were studied at Ensenada de Reyes, Mochima Bay, in the northeastern coast of Venezuela. Samples were taken monthly in six stations, three at 1 m in depth and three at 6 m, between December 1992 and February 1994, using a quadrat of 0.25 m2 for collecting plants and sediment; each sample was washed with seawater through a 1 mm sieve. The specimens were fixed in 6% formaldehyde. A total of 1722 organisms (6 888 ind x m2) and 127 species of macroinvertebrates were collected. Mollusks dominated with 53 species, followed by polychaetes (40), crustaceans (18) and echinoderms (8). Remaining groups were represented by 1-2 species. The highest abundance was in October (214 specimens), and the lowest in December 1993 (79 specimens). Specific richness was between 47 species in October and 18 in May 1993. Mean species diversity was 2.79-1.36 bits/ind. There were differences (ANOVA p<0.01) in number of specimens at the two depths but not throughout the 15 month study period (p>0.05). There were more specimens and species at the lowest depth and in stations with higher Thalassia testudinum biomass.  相似文献   

6.
Synopsis Abnormalities in five specimens of pleuronectiform flatfishes (one specimen from the family Soleidae, four from Bothidae) are described. The account of naturally occurring anomalies in the naked sole,Gymnachirus melas, is the first from the western Atlantic for a soleid other thanTrinectes maculatus. Anomalies inG. melas include partial albinism and osteological deformities. A second account of pigment and morphological aberrations is provided forParalichthys albigutta (total ambicoloration, incomplete eye rotation and hooked dorsal fin). Partial ambicoloration is reported for three specimens ofParalichthys lethostigma. Possible causes of abnormalities in flatfishes are reviewed. It is postulated that minimum depth of occurrence of species may be linked to frequency of abnormalities. Anomalies appear to be most frequent in species and families of flatfishes which inhabit shallow coastal or estuarine (<5 m depth) waters.  相似文献   

7.
One hundred and eighty-two new specimens of Parabrotula and 52 Leucobrotula are reported. Generic separation is confirmed. although premaxillary dentition no longer distinguishes the two. Two species of Parabrotula (one yet to be described) and one of Leucobrotula are strongly indicated from meristic data. Breeding biology is considered, with comment upon sexual dimorphism in size, size at maturity and possible breeding period. Parabrotulu plagiophthalmus Zugmayer, 1911 is shown to be a midwater non-migrant species (range 76@1500 m) with a temperature preference in the eastern North Atlantic of 9.0–5.0° C. Leucobrotulu udipatus Koefoed, 1952 exhibits a depth range of 61–1290 m and a temperature range of 9.0–4.2° C. Geographically it is evidently restricted to the North Atlantic and endemic to the eastern side. Most specimens were caught pelagically in the northwest African upwelling area in slope waters. Parabrotulaplagiophthalnius is distributed worldwide, although 89% came from the eastern North Atlantic.  相似文献   

8.
A new species of chimaeroid, Chimaera opalescens n. sp., was described from 31 type specimens caught in the north-eastern Atlantic Ocean at 950-1400 m depth. This species differed from all its congeners by the combination of the following characters: body uniformly pale brown to bronze, iridescent on fresh specimens; unpaired fins brown to purple, uniformly coloured or with pale or whitish edges; iris black; claspers tripartite and divided for a third of their length, not extending beyond the pelvic fins in adults; dorsal spine equal to or shorter than first dorsal fin; ventral caudal lobe equal to or deeper than dorsal caudal lobe. Comparison of DNA sequences of the CO1 gene with those of related species supported C. opalescens n. sp. as a distinct species. Specimens of C. opalescens n. sp. were previously misidentified as Chimaera monstrosa, a species sharing a similar geographical distribution. Chimaera opalescens n. sp. lives in deeper water and is a larger-bodied species than C. monstrosa. The two species were newly exploited by deep-sea fisheries and confused under a single landing name.  相似文献   

9.
Two octopod species are reported from the Canary Islands (eastern Atlantic Ocean) for the first time: the deep sea four-horn octopus, Pteroctopus tetracirrhus (Delle Chiaje, 1830) and the gelatinous giant octopus, Haliphron atlanticus Steenstrup, 1861. Both female specimens were caught in Tenerife. Haliphron atlanticus is described from fresh remains found floating close to the southwest coast and the second species, P. tetracirrhus, is described from a specimen captured in a shrimp trap at 200 m depth on the southeastern coast of Tenerife. With these two additions the revised and updated list of octopod species of the Canary Islands now comprises eight families and 18 species, all of them incirrate octopods. The zoogeographic relationships of octopod species from other Atlantic regions, including the Mediterranean Sea, were studied. The likely directions of faunal flows were inferred based on affinity indices, showing that Mauritania could be the most probable source of the octopod species of the Canary Islands and the rest of the Macaronesian archipelagos.  相似文献   

10.
2009年8月在广东省龙川县定南水河采集到一份弯枝藻属的标本,其形态特征介于弯枝藻(Compsopogon caeruleus)和疏枝弯枝藻(Csparsus)之间。植物体株高10~18cm,主轴直径180~270μm,微收缢;中轴细胞近球形和扁球形,横壁收缢明显,直径150-200μm,高100~110μm;皮层细胞1层,中轴细胞缢缩处为2—3层;多角形或卵形,长25~35μm,直径20-25μm;分枝直出至侧生,某些基部细胞特化为假根;分枝顶端渐尖、急尖或二叉状;单孢子球形,直径10—14μm。该标本可能为弯枝藻和疏枝弯枝藻在演化过程中的一种过渡类型。  相似文献   

11.
Over 2000 specimens of pycnogonid from deep-sea collections made in the northeastern Atlantic Ocean by IOS and SMBA between 1971 and 1994 have been analysed. Thirty-five species were identified, two being new to science, viz Nymphon akanthochoeros and an unnamed Anoplodactylus species. The deep-sea Pycnogonida of the northeastern Atlantic are reviewed using these data and records from the literature. Keys are presented for the six families represented by more than one species. The pycnogonid fauna of this area is characterized particularly by Paranymphon spinosum and Colossendeis clavata , with other dominant species including Colossendeis species, notably C. macenima , and Nymphon laterospinum, Anoplodactylus typhlops and A. arnaudae. Of the 54 species recorded below 200 m in the northeastern Atlantic, available evidence suggests that nine are 'endemic'. Relative distributions of the other species are discussed. A distinct change in the pycnogonid fauna with depth was found at around 1400 m. There is latitudinal separation of species groupings, shown most conspicuously by the shallower water species.  相似文献   

12.
An example of extreme morphological variation in a gyrodactylid monogenean is described. A specimen of Gyrodactylus pungitii collected from Pungitius pungitius at Crowland, Lincolnshire, UK, was found to have very short, slightly asymmetrical hamuli with roots only 12 and 15 µm long, compared to 16–28 µm in typical specimens of this species. When the specimen was cloned on G. aculeatus, the grand-daughter was found to be a typical specimen of G. pungitii. This extreme morphological variation, which was not inherited by the offspring, highlights the dangers of describing gyrodactylids from single small collections of parasites.  相似文献   

13.
Bathypterois mediterraneus was collected on 148 bottom trawls between 147 and 2251 m depth in the north-western Mediterranean. The species appeared below 700 m, its relative abundance and biomass increased progressively and reached its maximum at 2100-2300 m. A total of 1913 specimens were measured, ranging from 4 to 20 cm standard length ( L s). The size composition with depth did not show any specific trend, and no modal progression could be distinguished in the length frequency distribution by cruise, with dominance of large fish (13-15 cm L s) and a unimodal size pattern. The otoliths of 173 specimens were examined and showed the ring pattern common to teleost fishes. The age ranged between 0 and 15 years, although specimens of 4-12 years old were the most abundant. The growth parameters and the growth curve obtained from the interpretation of the growth rings in otoliths showed a low growth rate.  相似文献   

14.
Studies on an interesting Saccharomyces carlsbergensis mutant   总被引:1,自引:0,他引:1  
Summary 32 sputa from 29 patients known to have yeasts were emulsified and quantitatively plated on Sabouraud's glucose agar. Colony counts showed that the yeast flora varied from about 300 to about one million cells per ml of the specimen. Sputa collected at bed-side and plated within 2 hours gave lower counts than those received routinely. In the 28 specimens in which identification was carried outC. albicans was found in 23 as the only or the dominant species andC. tropicalis in 4; an unidentified species was present in one specimen.This work was supported by a Grant from the Medical Research Council, Ottawa, Canada.  相似文献   

15.
Brown A  Thatje S 《PloS one》2011,6(12):e28562
Depth zonation of fauna on continental margins is well documented. Whilst increasing hydrostatic pressure with depth has long been considered a factor contributing significantly to this pattern, discussion of the relative significance of decreasing temperature with depth has continued. This study investigates the physiological tolerances of fed and starved specimens of the bathyal lysianassoid amphipod Stephonyx biscayensis at varying temperature to acute pressure exposure by measuring the rate of oxygen consumption. Acclimation to atmospheric pressure is shown to have no significant interaction with temperature and/or pressure effects. Similarly, starvation is shown to have no significant effect on the interaction of temperature and pressure. Subsequently, the effect of pressure on respiration rate is revealed to be dependent on temperature: pressure equivalent to 2000 m depth was tolerated at 1 and 3°C; pressure equivalent to 2500 m depth was tolerated at 5.5°C; at 10°C pressure equivalent to 3000 m depth was tolerated. The variation in tolerance is consistent with the natural distribution range reported for this species. There are clear implications for hypotheses relating to the observed phenomenon of a biodiversity bottleneck between 2000 and 3000 metres, and for the potential for bathymetric range shifts in response to global climate change.  相似文献   

16.
Chromosomes of Poecilia mexicana mexicana, one of the bisexual species involved in the hybrid origin of the unisexual teleost fish species P. formosa, were analyzed by several staining techniques. Sex-specific, differential heterochromatin, found in other congeneric species, was not observed in P. m. mexicana. Nucleolar organizer regions were polymorphic among individual specimens within a given population sample. A single specimen exhibiting intraindividual variability of chromosome pair 1 and a specimen with a triploid karyotype are also described.  相似文献   

17.
To gain a better understanding of the natural function of fluorescent proteins, we have undertaken quantitative analyses of these proteins in a single species of coral, Montastraea cavernosa, residing around Turneffe atoll, on the Belizean Barrier Reef. We identified at least 10 members of a fluorescent protein family in this species, which consist of 4 distinct spectral classes. As much as a 10-fold change in the overall expression of fluorescent proteins was observed from specimen to specimen, suggesting that fluorescent proteins are dynamically regulated in response to environmental or physiological conditions. We found that the expression of some proteins was inversely correlated with depth, and that groups of proteins were coordinately expressed. There was no relationship between the expression of fluorescent proteins and the natural coloration of the Montastraea cavernosa specimens in this study. These findings have implications for current hypotheses regarding the properties and natural function of fluorescent proteins.  相似文献   

18.
Twenty-eight species of scleractinian corals were collected between 55 and 2,291 m depth during INDEMARES 2010–2012 expeditions to the Avilés Canyon System and the near continental shelf (Bay of Biscay). Most interesting species are described and all depicted. All species were already known from the northeast Atlantic, although some are seldom reported. Deltocyathus eccentricus and Flabellum chunii are northernmost records in the eastern Atlantic, and species first collected from the Bay of Biscay. From a literature review and new records given herein, 31 species of Scleractinia are known from the Avilés Canyon System. Live specimens of six species were recorded outside their previously known bathymetric ranges in the Bay of Biscay and nearby areas, either at shallower depths (Caryophyllia sarsiae, Monomyces pygmaea, Stephanocyathus nobilis), or deeper depths (C. atlantica, C. sarsiae, Enallopsammia rostrata, Solenosmilia variabilis). Desmophyllum cristagalli has the widest bathymetric range (551–2,291 m), and Lophelia pertusa is the most widely distributed species (24 stations). Tabulating the number of live species occurring in each 100-m depth interval of the canyon system, highest species richness occurs in the 700–800-, 800–900-, and 1,400–1,500-m depth intervals (11 species). The habitat-forming species L. pertusa and Madrepora oculata were abundant in some stations building well-developed coral banks. Live colonies of the big-sized species S. variabilis and E. rostrata co-occurred at the deepest station sampled that yielded scleractinia (2,291 m).  相似文献   

19.
Two specimens of Campylonotus arntzianus sp. nov. were caught in the Antarctic Scotia Sea off Saunders Island (57°40.31'S, 26°27.81'W) using an Agassiz trawl at one station (depth: 475-589 m). The new species described here is the fifth representative of the monogeneric family Campylonotidae, and the first of the family south of the Antarctic Convergence. Campylonotus arntzianus sp. nov. is a shrimp of about 5 cm in total length. Due to similarities in adult morphology, C. arntzianus sp. nov. seems to be closely related to C. capensis, a deep-sea species from the Southern Atlantic Ocean. A simple key for the species identification of the Campylonotidae is provided.  相似文献   

20.
The rare Randall's snapper Randallichthys filamentosus is recorded here for the first time in the eastern Indian Ocean from Scott Reef, north-western Australia. A single specimen of R. filamentosus , measuring 495 mm fork length, was captured on 9 July 2006 at a depth of 211 m on the outer reef slopes of Scott Reef. The capture of this specimen indicates that this deepwater fish is more widely distributed than was previously acknowledged and further implies that this species has a dispersal capacity that extends across ocean boundaries.  相似文献   

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