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1.
《Journal of Natural History》2012,46(23-24):3077-3089
The reefs of Rodrigues were some of the few reef areas in the Indian Ocean to escape the mass coral bleaching event of 1997–1998. However, during the last 2 weeks of February 2002 Rodrigues experienced sea-water temperatures over 30°C, clear skies and calm seas. Rapid assessments of the degree of coral bleaching and coral mortality were carried out at 22 sites around the coast of Rodrigues during March 2002. The surveys showed that the bleaching event in Rodrigues was not widespread, occurring at less than one-third of the sites surveyed and that coral mortality was restricted to sites in the north and west of the island. Where mortality did occur, it was severe, affecting up to 75% of corals at some sites. Coral species most vulnerable were Acropora cytherea and Acropora abrotanoides, which suffered up to 100% mortality. These colonies were still standing and had been very recently overgrown with turf algae. At present the reefs around Rodrigues are in good health, however, they are being impacted by over-fishing and sedimentation, and proposed developments have the potential to cause further damage to the reefs. It is likely that stressed corals will recover from bleaching events more slowly. It is therefore important that the coral reefs in Rodrigues are adequately protected from human impacts in order to increase their chances of surviving future bleaching events.  相似文献   

2.
《Journal of Natural History》2012,46(41-42):2639-2652
ABSTRACT

Two new species of siphonostomatoid copepods are described based on specimens collected off Tokara Islands located in the northern part of the Ryukyu Islands, Southern Japan. Cholomyzon multisetum sp. nov. (Coralliomyzontidae) found from the orange cup coral Tubastraea coccinea Lesson, 1829 (Hexacorallia: Scleractinia: Dendrophylliidae) has the following characters: armature formula of the antennule of the female; the outer lobe of the maxillule; and numbers of elements on the legs 1 to 3. Another species, Entomopsyllus takara sp. nov. (Entomolepididae), was found from both the Indo-Pacific blue coral Heliopora coerulea (Pallas, 1766) (Octocorallia: Helioporacea: Helioporidae) and the race coral Distichopora violacea (Pallas, 1766) (Hydrozoa: Anthoathecata: Stylasteridae). This new species of the male specimen is characterized by the antennule with shortest sixth segment, the endopod of leg 2 bearing two inner setae on the second segment and five setae on the third segment, the third exopodal and endopodal segments of leg 3 bearing three spines and three setae, respectively, and the third exopodal segment of leg 4 bearing four setae. These two species represented the first records of the families Coralliomyzontidae and Entomolepididae from Japanese waters.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:7C8DED0A-9CEB-405D-9BBF-FAF2043B0858  相似文献   

3.
《Journal of Natural History》2012,46(5):1197-1225
Fourteen species of gammaridean amphipod in the families Acanthonotozomatidae, Ampeliscidae, Ampithoidae, Anamixidae, Aoridae and Colomastigidae are recorded from coral rubble at Aqaba in the Red Sea. Nine species are recorded from the Red Sea for the first time, of which two are new to science.  相似文献   

4.
《Journal of Natural History》2012,46(6):1337-1346
The monotypic soft coral genus Malacacanthus has recently been rediscovered by means of scuba and is shown to be locally common and endemic in the shallow sublittoral of South Africa. Malacacanthus capensis (Hickson, 1900) is shown to be the proper taxonomic designation for the species. This species has previously been a problematic one due to the possession of several unusual morphological characteristics, including the total lack of sclerites and possession of a tough horny cuticle covering the stalk. The taxon is here shown to belong in the family Alcyoniidae by the possession of a full complement of mesenterial filaments, and not to the family Xeniidae as assigned by several previous authors. The species is here redescribed and the systematic status is revised. New observations on ecology and natural history from living colonies are also included.  相似文献   

5.
An updated list of over 200 species of corals from Cosmoledo and Aldabra atolls is presented, which more than doubles previously known species diversity, and establishes these atolls as amongst the most species-rich in the Western Indian Ocean. However, partly this is an artefact of a new method of recording with digital cameras, described here, which greatly improves recording efficiency. This is the first underwater study of Cosmoledo, and the first for Aldabra outside the expedition reports cited. The survey extended to >30 m depth, and comes after the 1998 massive coral mortality. Coral cover was virtually eliminated at that time to about 8-10 m depth in Cosmoledo on seaward slopes, below which coral mortality was only about 50%. Mortality was selective regarding different species, genera and families. Cosmoledo's lagoon of >150 km2 is shallower than the 'critical depth' of 8-10 m, resulting in an almost complete elimination of corals. To compare these atolls with other reefs in the region, critical depths are summarized for over 25 Indian Ocean locations. New coral recruits are abundant in the shallows of Cosmoledo and Aldabra 4 years later, though cover remains very low. Much bare rock remains (with turf algae) and some genera such as Acropora, previously apparently abundant, remain relatively very scarce. Apart from Porites, whose higher survival is now well documented, the best survivors from the 1998 mortality, and the most successful recruitment of new corals, are of faviids. Soft corals remain extremely scarce in all locations examined above the 'critical depth'. It is predicted that there may be a shift in the identity of the main species of corals in these atolls for many years.  相似文献   

6.
《Journal of Natural History》2012,46(8):1213-1222
An unusual new genus and species of coral inhabiting pontoniine shrimp from the Yemen is described and illustrated. The new shrimp is remarkable for its very small size and the unique form of its telson. Three other pontoniine shrimps are also reported from the Yemen for the first time, raising the number of such shrimp species known from southern Arabia to 18.  相似文献   

7.
The coastline of Oman extends 2000 km from 16.5°N to 26.5°N in the north-west Indian Ocean. Most of it is long, exposed sandy beach or mixed sand and shallow rocky areas subject to severe scour, and there is a seasonal, cold-water upwelling whose influence increases towards the equator. Three areas of the mainland support corals, separated by long stretches of shallow sandy or muddy sublittoral. Three categories of coral or reef development are recognized: (A) coral reefs develop with characteristic profiles of reef flat and reef slope; (B) corals provide framework but there is no reef growth and no characteristic reef profile; and (C) no true reef development occurs, but mixed coral/phaeophyte communities are attached directly on to old, often non-limestone substrate. A and B are common in the north and central regions but are rare in the south. Type C is found in the centre and especially the south where the poor reef development is more typical of marginal, high-latitude coral areas. Ninety-one coral species from 47 genera were recorded (77 species from 37 genera being zooxanthellate), although diversity declines towards the equator. Regional comparisons show the Oman fauna to be fairly similar (up to 63% similariy) to that of the Arabian Gulf, but relatively dissimilar to faunas of the Gulf of Kutch (20%) and Lakshadweep (35%), the only other areas known to have significant amounts of corals in the Arabian Sea. A new species of Acanthanstrea with calices 5–8 cm wide is described.  相似文献   

8.
《Journal of Natural History》2012,46(11):1597-1615
Over 8000 amphipods were examined from coastal (primarily intertidal) and anchialine pool habitats of Ascension Is. Twenty-seven species, of which 14 are undescribed, were identified. Comparison of species from Ascension with amphipods found in possible source areas suggests that most colonization of the island by these animals has been via the Benguela Current. Possible western Atlantic faunal contributions are significantly lower than for other marine taxa that have been studied at Ascension, all of which are generally characterized by having dispersive larval stages. The high proportion of apparently endemic species, which exceeds that described for amphipods of other oceanic islands, is probably due to both the island's isolation and incomplete faunal surveys in possible source areas. Amphipod species diversity is low, a probable consequence of the size, isolation, youth and low habitat variability of Ascension Is. Consistent with other Atlantic islands that have been studied, nestlers predominate (56% of the species), with tubicolous species (33%) of secondary importance and inquilines (11%) making only a minor contribution. Three species occur in the anchialine pool habitat. Rather unexpectedly, caprellid amphipods are absent.  相似文献   

9.
《Journal of Natural History》2012,46(41-42):2723-2743
ABSTRACT

In this study, we recognise the current physiographic characteristics of the Recife de Fora Marine Park (Royal Charlotte Bank, eastern Brazil) and describe the spatial pattern of the benthic community through reef habitats. Benthic assemblages differed from sectors and habitats, showing a marked coastal oceanic gradient. The results indicate that local environmental factors, such as coastal influence, exposure to waves, light radiation, and substrate inclination exert a strong influence on the structure of benthic communities. Seagrass banks predominated in the coastal sector, characterised by calm waters and greater influence of the continent. The reef walls showed high species richness, suggesting the formation of vertical light and temperature gradients. The oceanic sector showed a lower inclination of the substrate and was widely dominated by algae. Patch reefs encompass complementary physical conditions that are equivalent to those presented by other habitats, highlighting their importance with regard to the representation of physical and biological aspects of the local reef system. The main indicating organisms/categories suggest a balance between reef accretion and erosion processes. We emphasise the need for a continuous and standardised monitoring programme in order to understand the drivers of change in the distribution patterns of the communities, as well as to provide subsidies for conservation measures and adaptive management. The Recife de Fora Marine Park provides an interesting case study to explore the biophysical influences on benthic ecology and the dynamics of Brazilian shallow reefs.  相似文献   

10.
《Journal of Natural History》2012,46(31-32):1905-1924
Three new species of Astreopora (Hexacorallia: Scleractinia: Acroporidae), from Cenderawasih Bay in West Papua, exhibit morphological innovations for this conservative genus, extant since the Cretaceous. Two species are fully branching, a condition never previously described for Astreopora: Astreopora cenderawasih sp. nov. has dendritic branching, also seen in the confamilial genus Montipora, whereas branches of A. acroporina sp. nov. possess an axial corallite, regarded as the key morphological innovation facilitating rapid diversification and dominance of reefs in the younger, confamilial and most diverse genus Acropora (staghorn corals). We propose that these novel characters may be parallelisms indicating deep familial homologies. The third species, Astreopora montiporina sp. nov., has expansive coenosteum, reminiscent of plating Montipora. The new species form part of the most species-rich Astreopora assemblage reported to date, comprising 14 species. The unique tectonic and eustatic history of Cenderawasih Bay may have played a role in the evolution of these new species.  相似文献   

11.
《Journal of Natural History》2012,46(10):1233-1247
To explore the crustacean fauna associated with deep-water gorgonian corals, suction samples were taken from colonies of Paragorgia arborea and Primnoa resedaeformis using a Remotely Operated Vehicle. Seven colonies of P. arborea and eight of P. resedaeformis were sampled from 330–500?m depth in the Northeast Channel off Nova Scotia. A total of 17 species were identified as being associated with the corals. The P. arborea fauna was richer than the P. resedaeformis fauna in both abundance and number of species, with 1303 versus 102 individuals and 16 versus seven species, respectively. However, 13 of the species associated with P. arborea were from hydroids attached to the coral. Amphipods dominated the fauna both in abundance and numbers of species and the most common species were Metopa bruzelii, Stenopleustes malmgreni, Proboloides calcarata and Aeginella spinosa. The isopod Munna boecki and the cirripede Ornatoscalpellum stroemii were also quite common. The most strongly associated crustaceans were two parasitic poecilostomatid copepods; these are common also on tropical gorgonians and are most likely obligate associates. The frequently occurring shrimp Pandalus propinquus probably avoids predation by seeking protection among the coral branches. Shrimp counts from video records showed that visual inspection without physically disturbing colonies will generally not reveal the crustaceans hidden in coral colonies. The galatheid Eumunida picta was observed on P. resedaeformis colonies. The fauna of the deep-water gorgonians corresponded to the fauna of tropical shallow-water gorgonians in the numerical dominance of amphipods and parasitic copepods; however, species richness is higher and decapods, which constitute a rich fauna on tropical gorgonians, were only represented by two species.  相似文献   

12.
13.
In spiders, temperature is considered an important environmental variable for microhabitat selection. In this study, we evaluated the effect of temperature and rock size on the presence of the sand recluse spider Sicarius thomisoides and the degree of selectivity in different locations. This species is a large spider that lives under rocks in desert and semi-desert climates and is particularly active during the summer. In Chile, these spiders can be found at both coastal and inland locations under different thermal conditions, where usually the temperatures are lower near the coast. If large-scale climatic conditions are important for this species, they may be expected to select lower rock temperatures on the coast than at inland locations. In addition, we would expect that the spiders would choose larger rocks in inland compared to coast locations, which reduce the effect of high temperatures. We found that the probability of finding individuals of this species increased according to rock temperature and rock size in the field. Our results suggest that S. thomisoides prefers larger and warmer rocks to shelter under during the day, this selectivity being similar at both coastal and inland locations. Thus, this species tends to select rocks with the same thermal and structural conditions, independent of the climatic conditions.  相似文献   

14.
《Journal of Natural History》2012,46(23-24):3091-3102
The aim of this study was to create an inventory of the coral species which occur in the shallow waters around Rodrigues island. The stony corals of Rodrigues island have received limited study. Corals were recorded, photographed and collected from reef slopes and lagoons by scuba diving and snorkelling during October 2001. A collection of previously collected corals in Rodrigues was also studied. A total of 130 named species in 40 genera of hard corals (125 species in 37 genera of zooxanthellate Scleractinia) were found during the present survey, together with eight unidentified species; 47 species of coral were new records for Rodrigues, 37 of which were new reports for the southern Mascarene archipelago; 23 species represented extensions of their known ranges, including two species that were previously considered endemic to other areas. The number of species found is similar to that previously reported from Mauritius (134), and significantly more than reported in earlier studies of Rodriguan corals (up to 89 species). This also complements recent reports for Rodrigues (132 species) and Mauritius (163 species).  相似文献   

15.
《Journal of Natural History》2012,46(47-48):2985-3000
In a coastal salt-marsh of Spain, the digger wasp Stizus continuus primarily hunted for grasshoppers of the genus Heteracris, revealing (at least in the period of the study and in this area) this wasp to be almost monophagous. In contrast, grasshoppers of the genus Acrotylus were ignored by the wasps in spite of their high abundance in the environment. We hypothesize that this bias occurred because Acrotylus is found more often on the soil and on grasses, while Heteracris is nearly only found on Sarcocornia bushes, which probably represent the habitat mostly exploited by the wasps for hunting. The greater variance in size of the prey collected by larger females produced weak wasp–prey size correlations. Some wasps were observed to carry in flight prey weighing close to or more than the maximum theoretically possible, suggesting that they have to descend with prey to the nest from the above-soil hunting sites.  相似文献   

16.
《Journal of Natural History》2012,46(37-38):2285-2327
Two new Sarsiellinae from Ningaloo Reef, Spinacopia ningalooi sp. nov., and Metasarsiella caleyi sp. nov. are described. Spinacopia ningalooi is the first representative of the genus collected from a coral reef. It differs from the other species by its odd looking posterior infold. Metasarsiella caleyi sp. nov. is the first species of the genus reported from Australia. Keys to species of Spinacopia Kornicker, 1969 Kornicker, LS. 1969. Morphology, Ontogeny, and Intraspecific Variation of Spinacopia, a new genus of myodocopid ostracod (Sarsiellidae). Smith Contr Zool., 8: 50 [Google Scholar] and Metasarsiella Kornicker, 1991 Kornicker, LS. 1991. Myodocopid Ostracoda from Enewetak and Bikini Atolls. Smith Contr Zool., 505: 140 [Google Scholar], and to all the genera of Sarsiellinae are given here, together with an inventory of all the species and information on their distributions and biology. The results of two cladistic analyses (with unweighted and with weighted characters) of the subfamily based on 138 species and 34 morphological characters are presented. The first analysis resulted in seven equally parsimonious trees and the second in just one. The majority rule of the first group of trees and the tree from the second analysis are presented here.  相似文献   

17.
The study evaluated patterns of spatial variability of mobile macro-invertebrate assemblages associated with Posidonia oceanica leaves within a meadow at three different depths and three different coastal wave-exposures. A total of 171 taxa was found, among them two Nemertea, 65 Mollusca, 91 Arthropoda, eight Annelida and five Echinodermata. The total number of taxa per sample was higher in intermediate and deep stands than in shallow ones, while no significant differences among coastal wave-exposures were observed. Multivariate analyses detected significant differences in the structure of assemblages in relation to depth and coastal wave-exposure. Mollusca were more abundant in shallow stands, while Crustacea and Echinodermata increased in intermediate and deep stands. Moreover, patterns of spatial variability changed with depth: shallow and intermediate assemblages showed high small-scale (tens of metres apart) variability, while deep assemblages showed high variability at intermediate scale (hundreds of metres apart).  相似文献   

18.
The zooplankton species Oithona davisae is indigenous to coastal areas of Japan and the China Seas. It has, however, successfully invaded many other coastal marine regions such as San Francisco Bay, the Mediterranean Sea, the North Sea and the Black Sea. It is transported most probably in ballast water tanks. This is the first report of O. davisae in the coastal regions of the southern Black Sea (Anatolian coast). Based on monthly plankton sampling at two stations (Sürmene Bay), the seasonal dynamics of O. davisae were investigated. The highest abundance occurred at the coastal station (49,761 ind. m?3) in December and in October at the offshore station (8896 ind. m?3). The egg-carrying copepod O. davisae is more abundant in September (4571 ind. m?3) at the coastal station and in August (952 ind. m?3) at the offshore station. Expansion of this invasive copepod along the Black Sea coasts is reported by another country also. According to our results this invasive species may replace its native congener, Oithona nana. It can be hypothesized that O. davisae is one of the key species for energy transfer to the upper level of the food web from the microbial loop, which has recently become important in the Black Sea.  相似文献   

19.
The sagebrush biotype is the largest in the western United States. This vast sagebrush community is thought to harbor equally vast and diverse arthropod communities, but these remain little explored. Our objective was to examine the diversity, abundance, and seasonal phenology of arthropod taxa found on the dominant shrub of the sagebrush ecosystem, big sagebrush ( Artemisia tridentata ). We wanted to improve understanding of this little-studied arthropod assemblage that may play significant roles in the dynamics of sagebrush populations and the sagebrush ecosystem. We sampled free-living and gall-forming arthropods from a stratified random sample of sagebrush plants at the Barton Road Ecological Research Area, Idaho, resulting in a sample of over 8000 individuals and 232 morphospecies. Species richness and abundance declined from May to August, and abundance of most taxa similarly declined over the summer. A few taxa, including Acari (mites), were notably more abundant in August. Fluid feeders were the most diverse and abundant free-living feeding guild during all months and comprised up to 79% of morphospecies. The gall formers included 4713 individuals of 12 species of gall flies ( Rhopalomyia spp.), primarily (97%) R. ampullaria. Abundance of galls increased from small to large (presumably young to old) plants. Overall, A. tridentata was host to a high diversity of arthropods, some of which have potential to cause or mitigate significant damage to their host plant. Arthropods seem likely to have the greatest impact on sagebrush early in the growing season, when they are most diverse and abundant. Documentation of the full diversity of arthropods associated with sagebrush required samples taken throughout the growing season, but a single sample early in the growing season captured a high proportion of taxa.  相似文献   

20.
The American bullfrog Lithobates catesbeianus has been introduced around the world, with invasive populations reported from almost all South American countries. A population of this species was introduced in the Calingasta department of San Juan province, which is an arid environment in western Argentina. This work provides information on the dietary composition of an invasive population of L. catesbeianus, and compares the degree of dietary overlap between adults and juveniles. Stomach contents of 169 bullfrogs (82 adults and 87 juveniles) were analysed. Adults consumed 40 prey taxa and Hymenoptera (Insecta) was the most numerous prey item (41.8%), followed by Araneae (13.6%) and Aeglidae (13.4%). Juveniles consumed 29 prey taxa and Hymenoptera constituted the highest percentage in prey number (77.2%). The trophic overlap niche index at the same level shows a value of 0.64 overlap in dietary community between adults and juveniles of this bullfrog. Aeglidae was volumetrically the most important trophic item (25.4%), followed by Anura (25.02%). Our results showed that cannibalism in bullfrogs is more common than the consumption of native anurans, coinciding with that reported in other populations of introduced bullfrogs. The high similarity in the diets of both size classes and the association between the size of the predator and prey suggest that the impact caused by bullfrogs throughout their ontogeny is high and probably has an impact on their prey. Freshwater crabs are the main items in the diet of Lithobates catesbeianus in other introduced populations and are usually the most conspicuous at our study site. The crabs in freshwater ecosystems are part of the lowest trophic level in the food chain. The major threats to the southern region’s freshwater crabs include deforestation, farming and exotic species. Lithobates catesbeianus has a generalist diet and high overlap between adults and juveniles.  相似文献   

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