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1.
A small collection of fishes from the Bonaparte Seamount (15°40′S, 6°55′W, 130 km west of Saint Helena Island, least depth 105 m), comprising 14 specimens from nine species in eight families, is described. This appears to be the first collection of fishes reported from the seamount. In addition, seven new records for St Helena (15°58′S, 5°43′W) are reported as well as additional specimens of several rarely caught endemics. The scorpaenid Pontinus nigropunctatus, previously known only from St Helena, is now also reported from Bonaparte Seamount while the serranid Holanthias fronticinctus, also considered a St Helena endemic, has been found to comprise 20% of the diet of yellowfin tuna (Thunnus albacares) at the Seamount. The carangid Decapterus muroadsi which was previously recorded in the Atlantic only at St Helena is now also recorded from the Bonaparte Seamount. A second specimen of the primarily Indo-Pacific carangid Uraspis helvola is recorded from St Helena (third record for the Atlantic). Particularly interesting new records at St Helena, which represents significant range extensions, are of Corniger spinosus (Holocentridae), and of Carangoides ruber and Seriola fasciata (Carangidae). The potential role of shallow seamounts around Ascension and St Helena as ‘stepping stones’ between the two islands is discussed.  相似文献   

2.
Summary

The polychaete fauna of Careel Bay, Pittwater (33°37′S; 151°20′E) a sheltered estuarine area just north of Sydney, New South Wales, Australia is described. Some 57 species are described of which Parahalosydna chrysostichtus, Nereis posidoniae, Malacoceros divisus. Polydora penicillata. Prionospio multicristata. Nerinides vexillatus, Caulleriella tricapillata, Notomastus torquatus, Amphicteis dalmatica and Streblosoma acymatum are new species and 11 are new records for Australia. All previous Australian records are given for each species.  相似文献   

3.
《Journal of Natural History》2012,46(6):1367-1394
The pelagic fishes of St Helena Island, South Atlantic Ocean (15°58′S 5°43′W) are reviewed. A checklist of 53 taxa of pelagic fishes, with notes on fisheries significance, ecology and geographical distribution, is presented. Twelve of the taxa have not before been recorded at St Helena. Of particular interest are records of three primarily Indo-Pacific species: Decapterus muroadsi (Temminck and Schlegel), Uraspis helvola (Forster) and Scomberomorus commerson (Lacepède). Apart from U. helvola, which is known also from Ascension Island, these species are not otherwise recorded in the Atlantic Ocean.

Of the 49 pelagic fishes whose identities are clear, 81·6% are wide-ranging species known from both the Atlantic and Indo-Pacific regions, 12·2% are pan-Atlantic warm-water species and 4·1% are eastern Atlantic species which reach their western limit in the central Atlantic. In addition, the subspecies Platybelone argalus trachura is found only at St Helena and Ascension.

The principal pelagic species caught by St Helena fisheries are Katsuwonus pelamis, Thunnus albacares, T. obesus, T. alalunga, Scomber japonicus, Acanthocybium solandri and Pseudocaranx dentex, which together accounted for almost 95% of fish landings in 1982–1983 fiscal year.  相似文献   

4.
《Journal of Natural History》2012,46(25-26):1793-1804
The eumaeine hairstreak species Thecloxurina tegulina Bálint and Boyer, sp. n. from SW Peru, department Apurímac (type locality: Karkatera, NW of Ampay, 3,200 m, 13°34′286″S; 72°58′501″W) is described on the basis of qualitative and quantitative wing pattern, male genital and spectral characters. The spectral reflectance of the closely related genera Penaincisalia and Thecloxurina are investigated and compared. It is demonstrated that the spectral characteristics of the two genera are qualitatively differing, and the taxa investigated representing the two genera (Penaincisalia:Thecloxurina = 3:5) also have characteristic species dependent reflectance peaks measured at normal incidence.  相似文献   

5.
《Journal of Natural History》2012,46(23):2073-2082
In the present paper a microsporidian parasitic protist is described and characterized; it was observed in oocytes of Eurhomalea lenticularis Sowerby. The clams were obtained in Algarrobo, Chile (33°20′S, 71°40′W). The observations were made on 5?µm sections of female clam gonads, processed by routine histological techniques with ARTETA trichromic stain. According to the parasite's characteristics, it is established that the microsporidian protist is related to the genus Steinhausia (Chytridiopsidae). Microsporidian prevalence reached 20.6% (n?=?34) in summer months, but there was no evidences of cell damage in the oocyte of the host; in a total of 66 female clams, a 10.6% of infection was detected between December 1995 and August 1996. The infection intensity showed that 77.4% of the infested acini had single parasitized oocytes, and 88.0% of total oocytes parasitized contained only one cyst in the cytoplasm.  相似文献   

6.
A collection of Crustacea Isopoda (suborder Asellota) from a 10-year sampling programme in the Rockall Trough, NE Atlantic (54°40′N, 12°15′W) was analysed for evidence of breeding seasonality. No evidence of seasonal activity was found — adults and newly released juveniles were present throughout the year — but there was a strong seasonal pattern for breeding intensity. A significantly higher proportion of females was brooding during the winter months (25%) compared to the summer (5%), and the percentage of females brooding varied significantly with depth. The breeding pattern was synchronized to the seasonal deposition of organic detritus known to occur during the summer in the NE Atlantic. There were more newly released juveniles in samples during the summer than during the winter, with most females appearing to release their young at the time the deposition began. This deposition appears to be a major seasonal factor dominating the life-cycles of most benthic species in the Rockall Trough. Juvenile settlement for a range of taxa (echinoderms, molluscs and crustaceans) occurs while the detritus is present and most species maximize vitellogenesis at this time.  相似文献   

7.
《Journal of Natural History》2012,46(9):1429-1455
The Atlantic and Mediterranean species of the genus Andaniexis Stebbing, 1906 (Amphipoda: Stegocephalidae) are reviewed, and three new species are described. The species Andaniexis abyssi (Boeck, 1871) which previously was considered a widely distributed species (from Baffin Bay to both Spitzbergen and the Skagerrak), is here divided into three species: Andaniexis abyssi s.str., Andaniexis gracilis n.sp. and Andaniexis lupus n.sp. These species, together with Andaniexis mimonectes Ruffo, 1975, all have allopatric distributions. This is especially evident in northern Norway, where A. abyssi has its northernmost limit: A. abyssi is found in Solbergfjorden (69°10′N), while Andaniexis lupus is found in the adjacent fjord Malangen (69°30′N, the southern limit of this species along the Norwegian coast). Andaniexis eilae n.sp. is described from Iceland. This species is not closely related to the other North Atlantic species of the same genus.  相似文献   

8.
Hydrothermal fields on the Valu Fa Ridge at about 22°32′S, 176°43′W, were explored by the submersible Nautile during the French BIOLAU expedition in 1989. Pogonophorans were found during six of the 12 dives, at depths of about 1900 m. They were exposed to the influence of hydrothermal fluids but probably did not experience elevated temperatures. One new species of sediment-living perviate pogonophore was collected. Two new obturate pogonophores (vestimentiferans), one belonging to a new family, lived attached to hard substrata. There is a complete faunistic separation of the Lau Basin vestimentiferans from the eastern Pacific vent faunas. Families as well as genera are different, and the Lau species appear to have more in common with cold seep faunas.  相似文献   

9.
The embryonic development and reproductive strategy of Pseudorchestoidea brasiliensis, a talitrid amphipod of the supra- and midlittoral zones, were investigated by combining collections from June 1993 to May 1995 at Prainha, Rio de Janeiro (23°05′S and 43°25′W). The initial stage of embryonic development (I) was most frequent and was seen in about 70% of ovigerous females. Mean embryo volume in the final stage of development was almost twice that in the initial stage. Brood mortality between embryonic Stages I and IV was estimated at 11.42%. Multivoltism, continuous reproduction, low brood mortality (may be caused by better parental care with offspring) and the larger number of females than males in the population were indicated as compensating factors for the low fecundity observed in P. brasiliensis.  相似文献   

10.
Managing a rare species can be improved with knowledge of its natural history. The sheepnose (Plethobasus cyphyus) is a freshwater mussel recently listed by the US as federally endangered. We used standard methods to study P. cyphyus brooding behaviour, host fishes in the laboratory and under natural conditions, and glochidial morphology. We monitored a population of P. cyphyus in the Chippewa River, WI during spring and summer 2007–2009 and 2011 and found brooding animals between mid-May and early August. Gravid individuals ranged between 5 and 27 yr (mean age ± 1 s.d. = 13 ± 4 yr). Plethobasus cyphyus brooded glochidia in outer gills, which varied in colour from red, orange, pink, cream, or white. We observed mature glochidia more commonly in individuals with cream or white gills and these glochidia were released in a clear, adhesive, mucus matrix. In laboratory trials we found several minnow and topminnow species (29 spp.) served as productive suitable native hosts. The mean number of juvenile mussels released per cyprinid per day was significantly higher for trials conducted at 22–25°C compared with those at 18–20°C, and 83% of trials conducted at 18–20°C using suitable host species produced no juveniles. Glochidia had a unique outline and shell morphometrics that distinguished P. cyphyus from seven other Chippewa River mussel species that produce similar sized glochidia. Using morphometrics we determined that mimic shiners (Notropis volucellus) were natural hosts for P. cyphyus, round pigtoe (Pleurobema sintoxia), and Wabash pigtoe (Fusconaia flava). Releasing mucus-bound glochidia has evolved in a variety of mussel species and may be more common than is currently realized. Our data show that P. cyphyus is a cyprinid host specialist, and propagation efforts for this species can be strengthened through improved access to mature glochidia by using females with cream-coloured gills and increased juvenile production through warmer fish holding temperatures.  相似文献   

11.
《Journal of Natural History》2012,46(5-8):293-312
Over 4 years, daily counts recorded 830 Microplana scharffi, 2752 M. terrestris, and 108 of an unknown khaki Microplana species under wood, concrete, polythene, and a plank at a shaded site in a domestic garden. Numbers peaked in July and August. Microplana scharffi more often occurred under polythene, M. terrestris and the khaki species more often under wood. Cocoons peaked in June and July and hatchlings between July and September. Twelve M. terrestris cocoons yielded 50 hatchlings. Three M. scharffi cocoons yielded eight hatchlings. The time taken to hatch reduced from February to August. Earthworms accounted for 87% of M. scharffi prey. Microplana terrestris consumed earthworms, Arion hortensis and Discus rotundatus. Hatchling and unfed M. scharffi were yellow or cream. Fed individuals varied from pink to pale brown, depending on prey colour.  相似文献   

12.
《Journal of Natural History》2012,46(17-20):1047-1161
We found 39 cheilostome species among more than 7000 specimens collected at 10 intertidal sites in rocky habitats along the shore of Akkeshi Bay, eastern Hokkaido Island, Japan. These species are herein described in detail and illustrated by scanning electron microscopy. Nine species (23% of total) are described as new (Electra asiatica, Callopora sarae, Conopeum nakanosum, Cauloramphus cryptoarmatus, Cauloramphus multispinosus, Cauloramphus niger, Stomachetosella decorata, Microporella luellae, and Celleporina minima), and 21 species (54%) are reported for the first time from Japan. Species richness ranged from eight to 29 species per study site. A TWINSPAN analysis showed the species fell into nine groups defined by the local pattern of distribution. A cluster analysis of study sites based on similarity of species composition showed three faunistic groups distributed geographically: in Akkeshi Lake, along the eastern‐central shore of the bay, and at the mouth of the bay. Species richness in estuarine Akkeshi Lake was low, with a species composition very different from the outer bay. Most cheilostomes were found on rock and shell substrata, but uncommonly occurred on concrete walls, algae, hydroids, tubes of polychaetes, other bryozoans, and anthropogenic debris. Of the 39 species found, 33 (85%) contained embryos during the collecting periods, 2–7 June and 3–6 July 2004. The biogeographical composition of intertidal cheilostomes at Akkeshi Bay included species with Arctic‐Boreal (28%), Boreal (59%), and Boreal‐Subtropical (13%) distributions. The overall species richness of intertidal cheilostomes was two‐thirds that documented intertidally in a comparable study at Kodiak, Alaska, a locality 15° higher in latitude. We attribute the lower richness at Akkeshi to differences in the nearshore marine environment between the two localities.  相似文献   

13.
《Journal of Natural History》2012,46(5-6):359-373
The Chinese species of the genus Coccobius Ratzeburg (Hymenoptera: Aphelinidae) are reviewed. Sixteen species, C. abdominis Huang, C. annulicornis Ratzeburg, C. azumai Tachikawa, C. chaoi Huang, C. curtifuniculatus Huang, C. flaviceps (Girault & Dodd), C. flavicornis Compere & Annecke, C. fulvus (Compere & Annecke), C. furviflagellatus Huang, C. furvus Huang, C. languidus Huang, C. longialatus Huang, C. longifuniculatus Huang, C. maculatus Huang, C. wuyiensis Huang, and one new species, Coccobius albiscutellum Wang and Huang sp.nov., are treated. A key is provided for the recognition of the females of all Chinese species of Coccobius, and notes are given on their use in biological control of scale insect pests. http://www.zoobank.org/urn:lsid:zoobank.org:pub:F510059B-F176-46BA-B7B5-8252B06BE91F  相似文献   

14.
We studied reproduction of three species of crocodilians, Paleosuchus trigonatus, Caiman crocodilus and Melanosuchus niger, in the Xingu River, near the Belo Monte hydroelectric dam. The periods of laying and hatching of eggs were estimated for each nest before (2013–2014) and after (2016–2017) the river was dammed and the reservoir was formed. Nesting of the three species occurred between August and December, but was largely asynchronous; nest construction peaked in September for P. trigonatus, October for M. niger and November for C. crocodilus. Reservoir filling had little effect on the laying period of any of the species. Nests of P. trigonatus and M. niger were always within 0–12 m of the bank, whereas nests of C. crocodilus, which nests later in the season when flooding is more likely, were up to 100 m from the nearest water body. There was no relationship between distance from water and the number of eggs in nests, suggesting that larger and presumably more experienced females do not lay at different distances from the bank in any of the species.  相似文献   

15.
Project HABITATS was recently initiated in the Campos Basin (20.5–24° S), state of Rio de Janeiro, to assess biological impacts of petroleum exploration and exploitation on the continental shelf and slope of Brazil. Among species discovered in benthic samples from the area is the hydroid Monobrachium parasitum Mereschkowsky, 1877, occurring in an epibiotic association with the pelecypod mollusc Mendicula ferruginosa (Forbes, 1844): this is the first report of an association between the two species. Monobrachium parasitum has always been reported from cold waters, and is generally considered bipolar. This report records the occurrence of M. parasitum at lower latitudes, where they have seldom been collected: it is also the first account of this species from South America and the southwestern Atlantic. Moreover, the bathymetric distribution of M. parasitum is extended to a depth of 998 m. No previous records exist of hydroids from the Brazilian continental slope.  相似文献   

16.
17.
Summary

Monthly samples of the burrowing mud crab, Macrophthalmus hirtipes (Jacquinot 1853) were collected from February 1978 to April 1979 from a marine inlet, Governors Bay (43°38′S, 172°39′E) and from the Avon-Heathcote Estuary (43°33′S, 172°44′E), New Zealand. The estuarine population was generally unimodal and had an annual cycle of population change sustained by a concentrated summer recruitment. In contrast, the bay population was unimodal and bimodal at different times, and recruitment occurred thoughout the year with no clear peak. Both populations had equal sex ratios and were dominated by immature individuals (crabs?10·0 mm carapace width). Estuarine crabs were generally smaller than marine crabs.

At both sites, ovigerous females were found from late May to early March; the smallest egg-bearing female measured CW 10·0 mm at the estuary and CW 10·5 mm at the bay. Cycles of ovarian and embryological development were similar at the two localities. Three peaks of egg oviposition occurred within one breeding season and mature females were capable of producing successive broods. Fecundity was related exponentially to female carapace width and did not alter during the breeding season. Estuarine females carried more eggs than marine females of similar size. Egg volume was related to time of oviposition and eggs laid at the start of the breeding season were significantly larger than those deposited during the second half; however, estuarine eggs showed less reduction in size at this time than did marine eggs.

Estuarine sediments had higher levels of chlorophyll ‘a’, ATP, and microorganism activity and productivity than marine sediments. As M. hirtipes is a detritus feeder, the differences in food resources are believed to account for the elevated fecundity of estuarine crabs. At the bay, salinities were high with little tidal and seasonal variation, whereas in the estuary sea water was diluted significantly both daily and seasonally. The differences in salinity characteristics between the sites may be affecting larval distribution; recruitment in the estuary was concentrated to the summer and in the bay it was almost continuous.  相似文献   

18.
《Journal of Natural History》2012,46(3-4):227-251
Juvenile horseshoe crabs, Tachypleus tridentatus and Carcinoscorpius rotundicauda, with prosomal widths of between 11.5 and 102.5 mm, occur along Hong Kong's northwestern shoreline abutting Deep Bay where dissolved oxygen (DO) has been identified as the principal factor determining distribution and survival. Unreported upon hitherto, however, Tachypleus tridentatus occurred consistently in association with sea-grass (Halophila beccarii) beds, with DO concentrations of 8–14 mg·L?1, a median grain size of >180 μm, interstitial water contents of <36% (sediment wet weight) and organic contents of <3.2% (sediment dry weight). Most individuals occurred between 60 and 120 m down from the shoreline although there appeared to be a trend of down-shore migration in summer, possibly to alleviate thermal stress. No individuals were found at sediment temperatures ≤20°C, i.e. in sub-tropical Hong Kong's winter, when they adopt buried repose. Abundances of emerged T. tridentatus, peaking in November, were synchronized with interstitial salinities of 22–26‰ and averaged 1–2 individuals per 100 m2. Mean population density of T. tridentatus was 4–9 individuals per 100 m2. Only four individuals of C. rotundicauda were found in August and September, suggesting a recent dramatic decline in numbers. The natal crèche environment for juvenile horseshoe crabs in Hong Kong is deteriorating and threatening their survival.  相似文献   

19.
《Journal of Natural History》2012,46(29-30):1891-1910
One hundred and ninety-one frogs collected in Papua New Guinea from 10 species of the genus Litoria, namely, L. angiana, L. arfakiana, L. caerulea, L. congenita, L. eurynastes, L. gasconi, L. infrafrenata, L. iris, L. kumae and L. modica, were examined for helminths. Eighteen species of helminths were found: one species of Monogenea, Parapolystoma bulliense; three species of Digenea, Diplodiscus amphichrus, Halipegus zweifeli and Mesocoelium monas; 13 species of Nematoda, gravid specimens of Aplectana macintoshii, Cosmocerca novaeguineae, Falcaustra papuensis, Maxvachonia adamsoni, Maxvachonia flindersi, Maxvachonia ingens, Meteterakis crombiei, Moaciria moraveci, Parathelandros mastigurus, Physalopteroides milnensis, Pseudorictularia dipsarilis, Seuratascaris numidica, and larvae (in cysts) of Abbreviata sp. and, one species of Acanthocephala, Pseudoacanthocephalus bufonis. Mean number of helminth species per host species was 3.0 ± 1.4 SD (range 1–5), mean number of helminth species per infected frog was 1.1 ± 0.4 SD (range 1–2), and mean number of helminths per infected host was 33.3 ± 5.8 SD (range 1–36). Twenty-eight new host records and two new locality records are reported. The biogeography of the recovered helminths is discussed.  相似文献   

20.
A reappraisal of adult taxonomy of N.E. Atlantic and Mediterranean hermit crabs upholds the divisions A & B suggested for the species by MacDonal et al. (1957) from their studies of larval features. The nomenclature of three species is discussed. Pagurus variabilis (A. Milne Edwards and Bouvier, 1892) is relegated to the synonomy of P. alatus Fabricius, 1775 and P. excavatus (Herbst, 1791) is reinstated for Mediterranean and southern N. E. Atlantic material. A provisional check list is given of Paguroidean species occurring within the sea area 30°N–80°N:30°W–30°E and the Mediterranean Sea. An illustrated identification key is provided to the Pagurus species within these regions.  相似文献   

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