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1.
《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   

2.
3.
《Journal of Natural History》2012,46(6):1345-1381
Polystomoides scottae n. sp. is described from the urinary and accessory bladders of Chelodina expansa. Four species of Neopolystoma are described from the conjunctival sacs of Australian freshwater turtles (Chelidae): Neopolystoma cribbi n. sp. from Emydura signata, E. macquarii, Elseya latisternum and Chelodina expansa; Neopolystoma spratti n. sp. from Chelodina longicollis; Neopolystoma tinsleyi n. sp. from Chelodina expansa; and Neopolystoma queenslandensis n. sp. from Emydura signata and E. macquarii. Polystomoides australiensis, Neopolystoma macleayi and N. chelodinae are redescribed from new individuals. Neopolystoma australis is made a junior synonym of N. kreffti. P. australiensis, N. macleayi and N. cribbi produced on average 5·6, 4·3 and 0·7 eggs per day, respectively. Eggs of P. australiensis take 33–57 days at 18–24°C and 30–33 days at 24–28°C to develop and hatch. Oncomiracidia of P. australiensis and N. macleayi had 64 ciliated cells; the patterns of the ciliated cells are the same for both species. Different sizes of worms in different sites in the hosts suggest strongly that the oncomiracidia of P. australiensis and N. macleayi enter the host, migrate to the ureters, possibly to the kidneys, then to the urinary bladder and finally to either the accessory bladders or cloaca. Successful cross-infection experiments between host genera (Emydura to Elseya) indicated that P. australiensis and N. macleayi have a low degree of host specificity.  相似文献   

4.
《Journal of Natural History》2012,46(6):1597-1616
Eight Crisia and two Bicrisia species are recorded from the Celtic Sea (330–1175 m, Thalassa, 1973) and from both sides of the Straits of Gibraltar (110–903 m, Cryos, Balgim). Two new species are described: Crisia pyrula n. sp., and Bicrisia gibraltarensis n. sp. Systematics and morphology of five other species are detailed. A southern morphotype of C. aculeata is distinguished. Except for the boreal species B. abyssicola, all species occur both in Atlantic and Mediterranean localities. The upper bathyal crisiid fauna (>200 m) is richer in the Celtic Sea than in the Gibraltar area (6 spp. vs. 3 spp). Only three crisiids seem to be true deep-water species. The crisiid stock from stations located in the Gulf of Cadiz in Atlantic water is twice as rich as (1) that from stations of the same area washed by the Mediterranean water outflow; (2) that from the Alboran Sea.  相似文献   

5.
《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   

6.
The diversification of Mediterranean Phlebotomus species occurred during the Neogene and Quaternary periods. The climatic and geographical history of the Mediterranean area plausibly influenced the climatic requirements of recent sand fly species. Our aim was to investigate the European zoogeography and the climate-based ecological groups of eight Phlebotomus species considering the phylogeography of the studied taxa. Jaccard index calculation, hierarchical cluster and principal component analyses were performed. The results of Jaccard-coefficient calculations may indirectly refer to the former existence of three possible glacial refuges of sand fly populations in Europe: an Iberian, an Apennine and a Balkan Peninsula–Asia Minor refuge. Three main climatic groups of the studied sand fly species were distinguished, namely the so-called ‘Trans-Mediterranean’, ‘East Mediterranean’ and ‘West Mediterranean’ groups. Our results suggest that the ancestor of Phlebotomus similis and Phlebotomus sergenti was adapted to the hot, dry summer Mediterranean climate during the late Neogene. The third member of this climate group, Phlebotomus papatasi because of co-adaptation shows similar climatic requirements as P. similis and P. sergenti. The five Larroussius species studied should have evolved under moister climatic conditions. Species of the ‘West Mediterranean’ group were adapted to the milder and wetter oceanic climate of Atlantic coasts. The species of the ‘East Mediterranean’ group diversified under the less balanced climate of the East Mediterranean. The recent climatic requirements and the European distribution of the studied species is the consequence of the complex Quaternary–Neogene geographical and climatic history of their former habitats in the Old continent. The adaptation of the ancestors of the studied sand fly species to the changing geographical and climatic factors of Europe are discussed.  相似文献   

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8.
Species of the marine nematode genus Pontonema have been found to dominate the macrobenthos under abnormally high conditions of particulate organic enrichment. Populations from organically enriched habitats in six localities (Kiel fjord, Germany; the Garroch Head sewage-sludge dump ground in the Firth of Clyde, Scotland; Cornelian Bay, N.E. England; the Tyne estuary, N.E. England; Sete, N.W. Mediterranean, France; Blanes Bay, N.W. Mediterranean, Spain) have been compared. Multivariate analyses of 16 morphometric characters in males, and 13 in females, shows that each population is significantly different morphologically from every other population. However, there is morphological overlap between the populations, and it is considered pragmatic to recognize three species in this group, based on a few stable morphological characters: P. vulgare (Bastian, 1865) from the Baltic, P. alaeospicula Bett and Moore 1988 from the UK sites, and P. mediterranea sp. nov. from the Mediterranean. P. mediterranea sp. nov. is described. The species were not found to have established sympatry in this study, unlike many other opportunistic taxa from organically enriched habitats, and the significance of this is discussed.  相似文献   

9.
The Diplecogaster-ctenocrypta species-group is reviewed; it comprises two species. The clingfish Diplecogaster ctenocrypta from the Canary Islands is redescribed. The new species Diplecogaster tonstricula, a facultative cleaner of other teleosts, is described on the basis of eight specimens and colour photos from Senegal and the Canary Islands, eastern Atlantic Ocean. The species is small, apparently not exceeding 23 mm total length; it is characterised by having nine dorsal-fin rays, eight anal-fin rays, 24–25 pectoral-fin rays, 14–15 principal caudal-fin rays, 13–16 rakers on third gill arch, pelvic disc without lateral papillae in region A, disc region B with two rows of weak papillae, interorbital distance 4.1–4.6 in head length, distance between disc and anus 14–17% of SL, head and body with 10–13 narrow vertical brownish bars, cheek with a white ocellus surrounded by black, and with a small black spot in the middle. The new species is compared with other species of the genus; a key to the six known species of the eastern Atlantic, Mediterranean and Black Sea and South African genus Diplecogaster is presented. A checklist is provided for the species of Diplecogaster and their synonyms.  相似文献   

10.
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   

11.
A new species of the genus Phorbas Duchassaing and Michelotti, 1864 (junior synonym Anchinoe Gray, 1867) is described from the Aegean Sea (Eastern Mediterranean). Phorbas posidoni n.sp. is distinguished from the known Mediterranean species of Phorbas primarily by its elaborate repent-ramose habit combined with an extensive, spongin-enforced, plumoreticulate skeleton of oxea-like tornotes and the usual echinating acanthostyles and arcuate chelae. As in most Phorbas the surface bears characteristic areolae. The only other elaborate Mediterranean species, P. mercator (Schmidt) differs clearly in spiculation, since it lacks microscleres and has strongyles as the main skeletal elements. Phorbas fictitius (Bowerbank), P. tenacior (Topsent) and P. paupertas sensu Topsent are all incrusting and differ in spicule form and sizes as well. Likewise, Phorbas species from the neighbouring East Atlantic each show clear differences with P. posidoni n.sp. The genus Phorbas is discussed and compared with Pronax Gray (1867) sensu Lévi (1973). It is proposed to unite the two genera because the alleged sharp difference between the two (only oxea-like tornotes in the skeletal tracts in Phorbas, only acanthostyles in the skeletal tracts in Pronax) is compromised by a range of intermediate conditions in various species.  相似文献   

12.
《Journal of Natural History》2012,46(11):1639-1656
Trindade Island (20°30'S, 29°20'W) is located approximately 620 nautical miles (1160km) off the eastern Brazilian coast. Due to its geographical isolation, its ichthyofauna arouses great biogeographic interest. This work intends to provide the first comprehensive checklist for the shore fishes of Trindade Island. Six expeditions were undertaken (1995, 1997, two in 1998, 1999 and 2000—in total 86 days of fieldwork) to survey the ichthyofauna from tidal pools to reefs 30 m deep. A checklist of 97 species belonging to 44 families is presented, with information on the ecology and geographical distribution of each species. The most representative families were the Carangidae (nine species), Serranidae (nine), Labridae (seven), Pomacentridae (five) and Muraenidae (five). Trindade is zoogeographically related to the western Atlantic, since 32% of its species are also found in the continental margin and 12.3% are shared with the western and central Atlantic. Nearly thirty-five percent of the shore fish fauna of Trindade are widespread pan-Atlantic warm-water species. Another 14.6% are restricted to the Brazilian Province. At least six endemic species (6.2%) were found: Malacoctenus sp. (Labrisomidae), Scartella sp., Entomacrodus sp. (Blenniidae), Arcos sp. (Gobiesocidae), Elacatinus sp. and Lythrypinus sp. (Gobiidae). This endemism level is lower than that found on the tropical mid-Atlantic Ridge islands of St. Helena (13.9%), Ascension (15.7%) and St. Paul's Rocks (12.1%).  相似文献   

13.
The distribution pattern of purpleback flying squid and the relationship between its abundance and environmental variables in the south-eastern Arabian Sea were analysed using a geographical information system (GIS) and a generalised additive model (GAM). Highest abundances were observed during December and January within 10 and 13°N and 71 and 72°E around the Lakshadweep Islands. The mean abundance in the area was 4.21 tonnes/km2 and the maximum sustainable yield (MSY) was estimated as 0.63 million tonnes. GAM indicated that very high squid abundance was associated with low values of dissolved oxygen (6.01–6.27 mg/L), sea surface temperature (28.03–28.62°C), pH (7.75–8.56), salinity (30.42–34.48 psu), chlorophyll-a (0.4–0.6 mg/m3), zooplankton biomass (0.23–0.64 mL/m3), and shallow 20°C isotherm (101.2–134.7 m) and mixed layer depth (17.8–29.8 m). As a carnivore from paralarval stages, S. oualaniensis depends on secondary and tertiary production to sustain its population for which primary production is used up. In the tropical Arabian Sea where temperature differences are not so pronounced, S. oualaniensis distribution was found to be related to a low but very narrow sea surface temperature (SST) band. There is sufficient fishable biomass in the area to possibly launch a new targeted oceanic squid fishery from the western seaboard of India.  相似文献   

14.
Summary

For several decades there have been no reports on the black muntjac (Muntiacus crinifrons), and it has been listed as an endangered species. During the past few years we have discovered there are black muntjac in 37 countries of four provinces in east China. The geographical distribution is very narrow, and limited to the eastern part of China which lies between 28°–31°N. lat. and 117°–120°E. long. This paper describes the results of our study of the black muntjac. Details are given of the habitat and distributions of the 43 adult specimens captured and studied recently.  相似文献   

15.
《Journal of Natural History》2012,46(6):1591-1621
The tanaidacean tribe Agathotanaini, which was formerly the family Agathotanaidae, is well-represented in the Rockall Trough and Bay of Biscay areas of the North-east Atlantic. Five species have been recorded from depths of 1160–4829 m. Agathotanais ingolfi is the most numerous and one of the most widely distributed tanaidacean species in the region, and is often predominant in epibenthic sled samples from 1500–2500 m. Less numerous and frequent are three new species of Paragathotanais: P. nanus, P. robustus and P. gracilis. The first two are bathyal in distribution, and the last is abyssal. A new monospecific genus is established for Metagathotanais insulcatus, which has been recorded from the deepest part of the study region (4600–4800 m). Males of this tribe are characterized by their rigid pleopods bearing short terminal setae, and are otherwise very similar to the females. A key is provided for the identification of agathotanaids from the North-east Atlantic, including Agathotanais hanseni, and the genera Allodaposia and Paranarthrura, which should also be classified in the Agathotanaini.  相似文献   

16.
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   

17.
18.
《Journal of Natural History》2012,46(8):1119-1142
The present review is based on material from different localities in the Mediterranean Sea, and where appropriate, on type material; it comprises all Malmgreniella species known to occur in this area: i.e. Malmgreniella andreapolis (McIntosh, 1874), M. castanea (McIntosh, 1876), M. darbouxi Pettibone, 1993, M. lilianae Pettibone, 1993, M. ljungmani (Malmgren, 1867), M. lunulata (Delle Chiaje, 1830), M. polypapillata sp. nov. Two species are new for the Mediterranean: M. lilianae, previously only known from the southwest Atlantic, represents a new record, and M. polypapillata is a new species, occurring not only in the Mediterranean, but probably also in the northeast Atlantic. The seven Malmgreniella species listed above are described and figured, and an identification key is provided. Furthermore, the subfamily affiliation of the genus Malmgreniella Hartman, 1967 and the validity of Malmgrenia McIntosh, 1874 are discussed.  相似文献   

19.
Specimens of the genus Eumunida have been studied from various localities in the Atlantic Ocean. Comparisons of specimens from northwest and southwest Africa with material of E. picta from the western Atlantic Ocean has revealed two new species: E. bella nov. and E. squamifera sp. nov.

E. squamifera from the coast of Namibia, South West Africa, is distinguished from the two other atlantic species by a scaley striation of the carapace.

The northwest African E. bella and the western Atlantic E. picta, type of the genus, are closely related species, but differ from each other by the number and size of carapace marginal spines, shape of the anterior margin of the third thoracic sternum, and the ridges on the second abdominal segment. Their coloration is also different.

One specimen from the Tasman Sea identified by Gordon in 1930 as E. picta represents a further new taxon, E. australis sp. nov. It is readily distinguished from the three Atlantic species by the number of carapace anterio-lateral spines and the long acute projections of the third thoracic sternum.

All these species belong to the group A, as defined by Gordon (1930).  相似文献   

20.
《Journal of Natural History》2012,46(21-22):1365-1376
The relationship between myxomycetes and insects was investigated in a fragment of the Brazilian Atlantic Rainforest located in the city of Recife, Pernambuco, north-eastern Brazil. Sixteen excursions into the Dois Irmãos State Ecological Reserve (7°55′43′′ to 8°09′17′′ S, 34°52′05′′ to 35°00′59′′ W, 387.4 ha) were carried out during different seasons between August 2005 and August 2007 for observations and collections of myxomycetes and insects on decomposing trunks and leaf litter. A total of 196 specimens of myxomycetes was obtained, representing 31 species, 16 genera and six families. Baeocera sp. (Coleoptera, Staphylinidae) individuals predominated (86%) in the sample, found on the sporocarps of four species of Trichiales (Arcyria cinerea, Arcyria denudata, Hemitrichia calyculata, Hemitrichia serpula) and two species of Liceales (Lycogala epidendrum, Tubulifera microsperma). No preference was observed for type of sporocarp. No seasonal influence was found for the establishment of these associations, recorded for the first time in this forest environment.  相似文献   

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