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71.
ABSTRACT

Despite the accessibility of the Faroe Islands, faunistic research on their numerous lakes and ponds is quite rare. The biota of Faroese freshwaters is still underexplored, and its specific traits raise many questions. In the present survey, 32 microcrustacean species were observed, 8 of which were new to the Faroese fauna. The obtained species list shows that Cladocera species prevail over Copepoda here, which is not typical of northern territories. This fact is due to (1) the extraordinarily warm climate of the Faroe Islands compared to other areas at similar latitudes because of the heating effect of the surrounding North Atlantic Current and (2) the lack of calanoid species, which have never been found in the freshwaters of the Faroe Islands. The diachronic analysis of the species diversity and composition over the centuries of research on the archipelago showed no evidence of the impact of global climate change on the fauna.  相似文献   
72.
对影响江浙沿海台风的路径分布、发生频率等进行了系统分析,结果表明:影响江浙沿海的台风来自于西北太平洋和南海,其中90%以上生成于西北太平洋洋面,其余在南海生成。按其对江浙沿海的影响程度分类,得到影响江浙沿海台风的3种主要路径特征。台风主要在每年的5—11月进入江浙沿海,8月进入江浙沿海的台风数达到最大值;台风频数存在5—6年显著周期;21世纪以来进入江浙沿海的台风数逐渐减少,气旋能量逐年减弱。江浙沿海台风南多北少,浙江省(包括上海市)台风登陆次数较多,江苏省受台风影响相对较弱,基本无台风登陆。由于杭州湾附近特殊的水文环境和地形对台风路径的影响,成为奇特的台风零区,其附近基本无台风经过。  相似文献   
73.
《Journal of Natural History》2012,46(23-24):3229-3272
This checklist illustrates and comments on the 109 species of marine bivalve currently known from Rodrigues. The fauna appears impoverished when compared to those of Mauritius, Reunion and Seychelles. Low habitat diversity is postulated as the cause of impoverishment rather than the relatively young geological age of Rodrigues.  相似文献   
74.
Summary

Mussels up to 20·0 mm in length were examined for parasitism by Mytilicola intestinalis, and it was found that infection seldom occurs in mussels smaller than 10·0 mm.

Reasons for the low infection rate in young mussels have been discussed.

Female parasites in young mussels were significantly smaller than those living in adult mussels.  相似文献   
75.
《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   
76.
Examination of Fulgoroid specimens collected in several caves of volcanic origin on the Canary Islands (Tenerife, El Hierro) has revealed the existence of at least two undescribed troglobitic Fulgoroid species. These are apparently the first records of troglobitic Auchenorrhyncha, not only from the Middle Atlantic Islands, but from the Palaeartic Region. These cavernicolous taxa belong to the families Cixiidae (Tachycixius lavatubus sp. nov.) and Meenoplidae (Meenoplus cancavus sp. nov.). Possible pathways towards the evolution of troglobitic forms in Auchenorrhyncha and ways of speciation—sympatric or allopatric—for T. lavatubus sp. nov. and its epigean relative Tachycixius canariensis (Lindberg) are discussed. These findings suggest that cavernicolous Homoptera are more widely distributed over the world than was previously assumed.  相似文献   
77.
78.
《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   
79.
《Journal of Natural History》2012,46(21-24):1259-1300
Forty‐eight freshwater bodies on the Falkland Islands, including 33 lakes and pools, and 12 rivers and streams, were sampled for freshwater invertebrates. This study yielded 129 species of invertebrates (79 Rotifera, 34 Arthropoda, six Platyhelminthes, three Gastrotricha, two Nematoda, two Annelida, two Mollusca, and one Tardigrada) plus two fish species bringing the known Falkland Islands freshwater fauna to more than 170 species. While the presence of fishes, molluscs, amphipods, caddis larvae, waterboatmen, parasitic cercaria, and truly planktonic rotifers make the Falkland Islands fauna markedly richer than any subantarctic, or maritime Antarctic island, it is nevertheless sparse when compared with other temperate and tropical locations.  相似文献   
80.
《Journal of Natural History》2012,46(23-24):2959-3019
The marine benthic green and brown macroalgae of Rodrigues, collected during an expedition in October 2001, are documented and 18 of the 60 taxa of Chlorophyta (53 species) and 18 species of Phaeophyceae are illustrated. Fifty taxa of green and 12 taxa of brown algae are added to the existing species list of the island. Turf algae and smaller epiphytic species are not or are only sporadically included in this study. All records are listed with bibliographic, biogeographic, taxonomic and nomenclatural comments. Infrageneric identification keys are included. The new combination Caulerpa mexicana var. exposita is proposed and the discovery of a new Udotea species is mentioned. The algal flora of Rodrigues is of a typical Indian Ocean composition but appears to be relatively poor when compared to the nearby island of Mauritius.  相似文献   
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