Nematodes from a fresh-water pool on a coral island in the Solomon Islands

The present paper deals with the nematode species collected from a small deep fresh-water pool on a coral island in the Solomon Islands. 50% of the specimens recorded belong to terrestrial forms (4 species), 45% were marine forms (6 species) and only 5% belonged to fresh-water (4 species). Three species are described as new to science.     

Distribution et écologie des associations d’ostracodes récents de l’estuaire de Tahadart (Maroc Nord-Occidental)

Forty-five ostracod species were identified for the first time in the Tahadart estuary (NW Morocco). They can be grouped into five different ecological assemblages, which characterise four estuarine ecozones. A first ecozone occurs in temporary waters located between the tidal channels of the inner estuary and it is characterised by ostracod species typical of fresh to brackish waters. In the main estuary area, the ostracod fauna is dominated by clearly euryhaline species that account for nearly 70% of the entire fauna. The relative abundance of the different assemblages allows us to subdivide the estuarine environment along a longitudinal profile into mouth, outer and inner estuary. The estuary's mouth displays the highest values of marine euhaline, phytal and periphytal as well as ubiquitous species and the lowest values of very euryhaline species; the latter are the only species present in the inner estuary. The outer estuary exhibits intermediate percentages of the different ecological assemblages. This distribution, characterized by the absence of limnic species, points to the influence of marine waters in an open estuary with a low fresh water input. In the estuary's mouth, as well as in the outer estuary, where the slikke and schorre are well developed, the distance to the emersion line is underlined by the lower occurrence of marine and ubiquitous species and the higher occurrence of the very euryhaline ones. The Tahadart estuary displays a moderate to high ostracod diversity with distinct differences among the ecological zones. The stress of this environment is highlighted by the low diversity characteristics of extreme environments, alike in the inner estuary and in some areas located far from the emersion level. The relative position with respect to the emersion line, as well as the presence of gross detritic sediments and vegetation, appear to be of importance for the good development of the ostracods.     

Phytoplankton flora in the Warri/Forcados Estuary of southern Nigeria

The phytoplankton flora of the Warri/Forcados estuary varied from typical fresh and brackish water forms to purely distinct marine species. These were made up of members of the Bacillariophyta (about 80 species), Chlorophyta (over 90 species), Cyanophyta (16 species), Dinophyceae (10 species) and the Euglenophyta (8 species). The bulk of the species belonging to the Chlorophyta, Cyanophyta and the Euglenophyta were almost exclusively fresh-water in distribution, being limited to habitats of less than 0.5 salinity. Members of the Bacillariophyta were found in all habitats, occurring freely in freshwater, estuarine, and marine ecosystems. In all cases, no true examples of euryhalinity were recorded. The majority of dinoflagellates encountered, as well as a number of marine diatoms, manifested stenohaline peculiarities as they could not tolerate a wide salinity range.The overall influence of the periodic shift in salinity and some physico-chemical parameters along the stretch of the estuary brought about by strong tidal effects and the variable seasonal volume of water discharge or runoff on the pattern and limit of distribution of phytoplankton species is highlighted.     

中国长臂虾总科的动物地理学特点

本文讨论了长臂虾总科在中国分布的3个科,即拟贝隐虾科、叶颚虾科和长臂虾科的属、种在中国的分布情况及区系特点。拟贝隐虾科和叶颚虾科种类较少,分布于热带海域,我国分别在南沙群岛和西沙群岛发现1属1种和3属3种,均为广布的常见种。长臂虾科是本总科中种类最多、分布最广、十分常见的科,包括2亚科102属,世界性分布,海洋、淡水均有,我国大量分布。其起源中心应在印度－西太平洋暖水区,一部分浅海沿岸种经河口进入淡水水域, 大量发展,很少种可分布至温带区边缘;另一部分在热带珊瑚礁环境大量发展,并与许多动物类群共栖或共生。长臂虾亚科基本上是浅海－淡水自由生活类群,我国已记录9属61种,主要分布于南部,多数为东洋界热带和亚热带种,分别属东洋界(淡水)和印度－西太平洋区(海水、半咸水);而极少数种分布至北方,温带性的淡水种有2种白虾,1种小长臂虾和仅见于东北部的条纹长臂虾,属于古北界区系(淡水),海水种有黄、东海的敖氏长臂虾及细指长臂虾,属于北太平洋温带区系(海水、半咸水)。隐虾亚科全部为海洋种,主要分布在热带、亚热带海域,以珊瑚礁为主要栖息地,大部分分布于印度－西太平洋海域,80%以上的种类或多或少与其他海洋生物共栖,自由生活的种很少。根据推论,隐虾类的起源中心应在印度－西太平洋热带水域的珊瑚礁环境, 并在这一水域得到了充分的分化与发展,分别适应与腔肠动物、双壳类软体动物、海绵动物、棘皮动物和海鞘类被囊动物共栖生活;而热带美洲的类群则是在隐虾类演化到可与石珊瑚类共栖时由印度－西太平洋水域扩散过去的, 共栖宿主仅涉及腔肠动物和棘皮动物。我国南海水域已发现31属96种,极少数种也分布到东海,属于印度－西太平洋热带水域珊瑚礁区系。     

An outbreak of schistosomiasis in Atlantic brant geese, Branta bernicla hrota

A heavy infection with schistosomes of the genera Trichobilharzia and Dendritobilharzia was considered the cause of 90% mortality in a group of 40 wild-caught Atlantic brant geese (Branta bernicla hrota) that were maintained in captivity on a fresh-water pond in Aurora, Ontario. Numerous adult worms and eggs were disseminated in many organs throughout the body of all birds examined. The main pathological findings, attributed to both eggs and adults, included emaciation, thrombosis of the caudal mesenteric vein and its branches, fibrinohemorrhagic colitis, and in some birds, heptomegaly. Translocation of brant geese from their natural marine environment to a fresh-water pond may have caused them to be exposed to parasites which they would not normally encounter.     

Transition from Water to Land in Decapod Crustaceans

In the Order Decapoda four families of Macrura, one of Anomura,and seven of Brachyura include semi-terrestrial or terrestrialrepresentatives, primarily tropical and subtropical in distribution. Observations have been made largely on brachyurans. In theseforms mating takes place on land, and courtship involves mainlyvisual and acoustic signals rather than chemical and tactileones. During copulation the female is often hard rather thansoft and may assume a position above the male rather than beneathhim, as in many marine forms. Eggs are carried by the femaleon land. Larval development takes place either in sea wateror, in the case of some fresh-water crayfishes and crabs, entirelywithin the egg. Extremes of temperature are met primarily by acclimation, transpiration,or escape (immersion, burrowing). During transpiration bodytemperature is lowered by a few degrees but water is lost. Insome species water can be replenished by uptake from a moistsubstratum and stored within the pericardial sacs. Ionic regulation occurs largely through antennal glands, gills,and gut and helps to move water from exterior into hemolymphand from hemolymph into gut and its diverticula. In Gecarcinuslateralis at ecdysis, large amounts of water move from hemolymphinto gut, this process being controlled by a hormone from thethoracic ganglionic mass.     

The freshwater Crustacea of the island of Rhum (Inner Hebrides),

A survey of the freshwater crustacean fauna of the island of Rhum (Inner Hebrides) revealed at least 68 species. Information is provided on die distribution and ecology of these, and individual preferences are noted. These preferences lead to assemblages found in habitats whose ecological attributes can be related to geological, edaphic and chemical features of the environment.
While species diversity on the island as a whole is perhaps greater than might have been anticipated, that of individual water bodies tends to be low, the maximum number ol species in any one water body being 2 7.
The fauna includes a sizeable element of species that favour acidic waters of various kinds or oligotropliic/dystrophic lakes and pools of low ionic content, and includes a number of northern or burco-Alpine species. The origin of this isolated fauna is briefly considered.     

Australian barnacles (cirripedia: thoracica), distributions and biogeographical affinities

Currently, 279 barnacle species are recognized in Australia waters. The barnacle fauna of tropical Australia exhibits high species diversity (221), with a high incidence of tropical species (87 Indo-west Pacific [IWP], 16 West Pacific and 65 Indo-Malayan), a low species endemicity (8), and 44 cosmopolitan and 1 Australasian species. Conversely, that of temperate Australia shows lower species diversity (129), with a lower incidence of tropical species (26 IWP, 10 West Pacific and 25 Indo-Malayan), higher species endemicity (23), 37 cosmopolitan, 6 Australasian species, and 3 Australasian/Antarctic species. Distributions corroborate the general patterns demonstrated by the shallow-water biota of northern tropical and southern temperate Australian biogeographic provinces. Tropical and temperate provinces grade into each other in a broad overlap zone along both the western and eastern Australian coasts. This overlap zone is essentially a transitional region, with the gradual replacement of a tropical barnacle fauna in the north by a predominantly temperate barnacle fauna in the south. Both western and eastern Australian coasts are bounded by major poleward-flowing warm currents that have considerable influence on the marine flora and fauna, distributing tropical species of many taxa much farther south than could be predicted by latitude. Currently, 16 barnacle species introduced into Australian waters are identified, although this number may increase in the future due to new port developments and increased shipping arrivals.     

Early Jurassic shell beds from marginal marine environments in southern Mendoza, Argentina

External estuarine facies in Late Sinemurian beds from the base of the Puesto Araya Formation in the Atuel river region, Mendoza Province, Argentina, contain concentrations of a new species of Cardinioides (a shallow burrowing suspension-feeding Pachycardiidae bivalve) and a low diversity benthic fauna. These bivalves appear in tidal inlet facies of a wave-dominated estuary (environment similar to lagoon-barrier island systems), forming bioclastic lags at the channel bases. The taphonomic attributes (such as shell articulation, degree of fragmentation and abrasion, bioclast size, orientation) change from North to South, from monospecific concentrations of nearly complete large Cardinioides shells with low degree of fragmentation and abrasion, through beds with smaller Cardinioides shells associated with a few bivalves from marine environments, to only isolated fragmented specimens associated with a fully marine biota including not only other bivalves but also brachiopods and ammonoids. This, together with different palaeoecologic, sedimentologic and stratigraphic attributes at the studied localities are evidence of southwards changing environmental conditions from marginal marine (brackish) to fully marine on the eastern margin of the Neuquén basin at that time. From detailed analysis of taphonomic features, size distribution of shells, and the associated fauna at the different localities, the new species is regarded as a brackish water endemic, possibly a low salinity euryhaline species, which inhabited well oxygenated waters. Salinity, turbulence levels and food supply were the main limiting factors in the distribution of the species.     

Revealing the appetite of the marine aquarium fish trade: the volume and biodiversity of fish imported into the United States

The aquarium trade and other wildlife consumers are at a crossroads forced by threats from global climate change and other anthropogenic stressors that have weakened coastal ecosystems. While the wildlife trade may put additional stress on coral reefs, it brings income into impoverished parts of the world and may stimulate interest in marine conservation. To better understand the influence of the trade, we must first be able to quantify coral reef fauna moving through it. Herein, we discuss the lack of a data system for monitoring the wildlife aquarium trade and analyze problems that arise when trying to monitor the trade using a system not specifically designed for this purpose. To do this, we examined an entire year of import records of marine tropical fish entering the United States in detail, and discuss the relationship between trade volume, biodiversity and introduction of non-native marine fishes. Our analyses showed that biodiversity levels are higher than previous estimates. Additionally, more than half of government importation forms have numerical or other reporting discrepancies resulting in the overestimation of trade volumes by 27%. While some commonly imported species have been introduced into the coastal waters of the USA (as expected), we also found that some uncommon species in the trade have also been introduced. This is the first study of aquarium trade imports to compare commercial invoices to government forms and provides a means to, routinely and in real time, examine the biodiversity of the trade in coral reef wildlife species.     

人工鱼礁建设对浙江嵊泗海域营养盐与水质的影响

根据2003-2007年对嵊泗人工鱼礁海域11个航次调查所获得的实验数据,运用鱼礁区和对照区相比较的方法,分析了该海域不同季节氮、磷营养盐和水质在投放人工鱼礁后的变化,并对海域水质状况进行评价。结果表明,无机氮大多数处于阈值范围或低于最小阈值,活性磷酸盐含量则严重超标,N/P值范围为0.6280-14.8273,嵊泗海域处于氮限制,溶解氧不成为该海域浮游生物的生长限制因子。投放人工鱼礁后,生态效应不能在短期里得以体现,鱼礁区的水质情况要好于对照区,海域对P的富集强度大于N,人工鱼礁建设对再生生产力影响较大,对新生产力的贡献很小。       

THE LATE TRIASSIC BLACK SHALES OF THE GUANLING AREA, GUIZHOU PROVINCE, SOUTH-WEST CHINA: A UNIQUE MARINE REPTILE AND PELAGIC CRINOID FOSSIL LAGERSTÄTTE

Abstract:  Black shales of the lower member of the Carnian Xiaowa Formation (previously known as the Wayao Member of the Falang Formation or as the Wayao Formation) in the Guanling area, Guizhou Province, south-west China, are yielding a rich marine reptile fauna and exceptional remains of pelagic crinoids. The black shales represent deposition on the drowned southern margin of the Yangtze Platform during a Maximum Flooding Interval. The relatively reduced sedimentation rates led to the formation of the Lagerstätte through the accumulation of fossils in the anoxic bottom sediments over a prolonged period of time. Invertebrate fossils represent almost exclusively pelagic forms, such as a diverse ammonite fauna and halobiid bivalves. The spectacular finds of colonies of large (stem lengths > 11 m) crinoids of the genus Traumatocrinus attached to driftwood prove that this crinoid was the first to evolve a pseudoplanktonic life style. The other crinoid is the planktonic roveacrinid Osteocrinus . The marine reptile fauna, represented by probably hundreds of skeletons, is numerically dominated by three species of ichthyosaurs and four species of thalattosaurs. The thalattosaurs fill a palaeobiogeographic gap between the Alpine thalattosaur faunas and those from western North America. Two species of placodonts are rare finds. As for the thalattosaurs, the placodont occurrences greatly expand the geographic range of the group because placodonts have been known previously only from the Mediterranean region, the Alps and the Muschelkalk Basin. The unique abundance of thalattosaurs contrasts with a scarcity of fishes. Although we suggest that the fauna is authochthonous and inhabited surface waters, it must have represented an unusual ecosystem. However, the possibility remains that both the marine reptiles and the Traumatocrinus colonies were concentrated in the region by currents and do not reflect the biocoenosis.     

Historical Zoogeography of the Eusuchian Crocodilians: A Physiological Perspective

The historical zoogeography of eusuchian crocodilians has rarelybeen reviewed in any detail and yet is of increasing interestto students of crocodilian biology as large amounts of comparativeinformation on a wide range of species come to hand. Previousinterpretations of crocodilian zoogeography have been basedon one or another of two assumptions–that the major continentalland masses have remained more or less fixed in position, andthat the eusuchians have had only very limited powers of dispersalacross marine barriers. Both of these assumptions are inappropriatein light of our present knowledge of continental drift and crocodilianphysiology. In this paper we attempt a reinterpretation of eusuchian zoogeographybased on new information on their systematic relationships,physiological capacity for marine dispersal, and fossil history.We postulate that anatomical and physiological adaptations toa marine existence have played an important role in eusuchianhistory. We propose that Gavialis and Tomistoma, now restrictedto fresh waters, may have been derived secondarily from ancestorsadapted to salt water. In the case of Tomistoma, similaritiesin lingual gland and buccal cavity anatomy to the true crocodiles(Crocodylus and Osteolaemus) suggest that marine adaptationspredated the divergence of tomistomine and crocodyline stocks.The buccal morphology of Gavialis suggests it also has a marineancestry. Its systematic affinities are uncertain, lying perhapswith Tomistoma or, on other interpretations, with the Mesosuchia.In both cases, the fossil record is not inconsistent with thispossibility. Palaeontological information now available is inadequate toreconstruct the evolutionary history of the Eusuchia in detail.However, saltwater adapted eusuchians are more common in thefossil record than is widely recognized and the likelihood ofdispersal across marine "barriers" by non-alligatorid crocodilianscannot be ignored.     

Changes in the Aral Sea ecosystems during the period 1960–1990

Salt and water balance in the Aral Sea are described together with the endemic fauna and flora which were mainly of freshwater origin. During the last thirty years the fauna and flora have undergone dramatic changes due partly to a great increase in salinity as the result of water abstraction from the inflowing rivers and partly as the result of the deliberate and accidental introduction of a wide variety of marine invertebrates and fishes. The increased salinity has eliminated most the species of freshwater origin while many of endemic saline species have been lost as the result of competition with the marine ones. Changes in productivity are described and future prospects for the sea are discussed.     

THE BIOLOGY AND FUNCTIONAL MORPHOLOGY OF MYTILOPSIS SALLEI (RECLUZ) (BIVALVIA: DREISSENACEA) FOULING VISAKHAPATNAM HARBOUR, ANDHRA PRADESH, INDIA

Mytilopsis sallei (Récluz) (Dreissenacea) has been introducedinto Visakhapatnam harbour, India. The normal distribution ofthe species is Central America and it is here contended thatthe species has been introduced into the Indo-Pacific via thePanama canal (opened in 1915) attached to the hulls of ships.M. allyneana (Hertlein & Hanna) with a distribution restrictedto Fiji is considered synonymous with M. sallei. The literature on M. sallei is reviewed and it is shown thatthe species has wide temperature, salinity and oxygen tolerancesand thus transport across a variety of water masses is entirelyfeasible. The species also possesses a fast rate of growth,a high fecundity and matures early. It is an opportunistic specieswhich free from the restraints that normally hold it in checkin its natural environment, poses a serious fouling threat toharbours throughout the Indo-Pacific and to the endemic fauna. The morphological adaptations of M. sallei are also describedand compared with those of Dreissena polymorpha (Pallas) inparticular and other fouling bivalves in general. The speciesis ideally adapted to life in turbid estuaries experiencingwide variations in temperature, salinity, oxygen and turbulence.A warning against further introductions is given. (Received 14 December 1979;     

Evolution and Diversification of Antarctic Notothenioid Fishes

Antarctica supported fossil ichthyofaunas during the Devonian,Jurassic, Cretaceous and Eocene/Oligocene. These faunas arenot ancestral to each other, nor are they related to any componentof the modern fauna. About one hundred species of notothenioidsdominate a modern fauna of over 200 species of bottom fishes.This highly endemic perciform suborder is not representedinthe fossil record of Antarctica. Notothenioids may have evolvedin situ on the margins of the Antarctic continent while graduallyadapting to cooling conditions during the Tertiary. Cladisticstudies indicate that notothenioids are a monophyletic group,but a sister group has not been identified among perciform fishes.With relatively few non-notothenioid fishes in Antarctic waters,notothenioids fill ecological roles normally occupied by taxonomicallydiverse fishes in temperate waters. There are six notothenioidfamilies: Bovichtidae, Nototheniidae, Harpagiferidae, Artedidraconidae,Bathydraconidae and Channichthyidae. Aspects of theirbiologyare briefly considered with emphasis on the Nototheniidae, themost speciose family. Evolutionary diversification within thisfamily allows recognition of species which are pelagic, cryopelagic,benthopelagic and benthic.     

The Role of Microorganisms in Transformation of Selenium in Marine Waters

The activity of microorganisms is a decisive factor in the transformation of the essential and, at the same time, toxic selenium (Se) in marine waters. This review provides an analysis of the literature data on the microbiological regulation of the state of Se in marine waters: the role of microorganisms in eliminating toxic Se from marine waters through precipitation of reduced Se forms and in the reverse process, transformation of Se into a form available to be taken up by organisms and involvement of this element in the biogeochemical cycle. The processes of transformation of the oxidized and reduced Se forms with the participation of microorganisms in marine waters are considered. It has been shown that in anaerobic conditions bacteria use the oxidized Se forms as electron acceptors (reduction). Bioavailable selenite and selenate ions are formed in the case of aerobic oxidation. Biotransformation of dissolved Se is a key mechanism for the formation of methylated gaseous Se forms in marine waters as one of the ways to remove this element from the aquatic environment.     

Diversity of the free-living marine and freshwater Copepoda (Crustacea) in Costa Rica: a review

The studies on marine copepods of Costa Rica started in the 1990’s and focused on the largest coastal-estuarine systems in the country, particularly along the Pacific coast. Diversity is widely variable among these systems: 40 species have been recorded in the Culebra Bay influenced by upwelling, northern Pacific coast, only 12 in the Gulf of Nicoya estuarine system, and 38 in Golfo Dulce, an anoxic basin in the southern Pacific coast of the country. Freshwater environments of Costa Rica are known to harbor a moderate diversity of continental copepods (25 species), which includes 6 calanoids, 17 cyclopoids and only two harpacticoids. Of the +100 freshwater species recorded in Central America, six are known only from Costa Rica, and one appears to be endemic to this country. The freshwater copepod fauna of Costa Rica is clearly the best known in Central America. Overall, six of the 10 orders of Copepoda are reported from Costa Rica. A previous summary by 2001 of the free-living copepod diversity in the country included 80 marine species (67 pelagic, 13 benthic). By 2009, the number of marine species increased to 209: 164 from the Pacific (49% of the copepod fauna from the Eastern Tropical Pacific) and 45 from the Caribbean coast (8% of species known from the Caribbean Basin). Both the Caribbean and Pacific species lists are growing. Additional collections of copepods at Cocos Island, an oceanic island 530 km away of the Pacific coast, have revealed many new records, including five new marine species from Costa Rica. Currently, the known diversity of marine copepods of Costa Rica is still in development and represents up to 52.6% of the total marine microcrustaceans recorded in the country. Future sampling and taxonomic efforts in the marine habitats should emphasize oceanic environments including deep waters but also littoral communities. Several Costa Rican records of freshwater copepods are likely to represent undescribed species. Also, the biogeographic relevance of the inland copepod fauna of Costa Rica requires more detailed surveys.     

福建平潭岛海域底栖贝类物种多样性及其地理分布

海洋底栖贝类是海洋底栖无脊椎动物的重要代表。福建平潭岛地处台湾海峡西岸北部, 是中国大陆距台湾岛最近之处, 其海域内的底栖贝类区系对了解台湾海峡及其附近海域的生态环境和底栖生物地理格局具有重要意义。本文基于对2015-2018年间中山大学国土资源与环境系在平潭岛海域采集的3,346号底栖贝类标本的鉴定, 结合已发表文献整理出了平潭岛海域底栖贝类名录, 并梳理了各物种在中国近海的地理分布类型。结果显示, 本研究所采标本分属58科122属161种, 其中47种为平潭岛海域新记录。结合历史文献记录, 平潭岛海域共有底栖贝类98科244属395种。其中93.7%的种类在南海亦有分布, 82.0%的种类在东海有分布, 31.1%的种类在黄渤海有分布, 42.3%的种类在台湾岛东部海域有分布。南海-东海分布型种类占区系总种数的49.9%; 其次为南海-黄渤海分布型(27.6%)和南海-台湾海峡分布型(16.2%)。分布限于台湾海峡及其以北的种类仅占总种数的6.3%。研究结果表明, 平潭岛海域底栖贝类区系具典型的亚热带性质, 暖水性种类和广温性种类占主要优势, 与南海北部和东海大陆沿岸地区的关系密切, 与台湾岛周边海域的联系相对较弱。     

The palaeopsychrosphere in the Devonian

The interpretation of Palaeozoic marine benthonic ostracods of the Thuringian ‘Ecotype’ or ‘Mega‐assemblage’ as indicative of a palaeopsychrosphere has been controversial. We review the evidence and conclude that the characteristics and distribution of these ostracods are consistent with the existence of deep, cold, well‐oxygenated water masses, formed by high‐latitude sinking of surface waters, in the Devonian oceans, comparable with those of the modern ocean that constitute the psychrosphere (waters below the thermocline with temperature <10°C). We present a new palaeoceanographic model for the Frasnian–Famennian (Late Devonian) Kellwasser events that resulted in the extinction of 75% of marine ostracod taxa, mostly neritic or pelagic forms, while the deep water Thuringian Mega‐assemblage was relatively unaffected. We offer an explanation for the unlikely preservation of examples of such a deep water (bathyal to abyssal) ostracod fauna that involves upwelling of deep cold waters on continental margins.