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21.
Lernanthropus antofagastensis sp. nov., parasitic on Anisotremus scapularis, and inshore fish of Antofagasta, Chile, is described and illustrated. It resembles five other species of Lernanthropus in its dorsal plate and third leg, but can be distinguished from them by a combination of characters. L. trachuri Brian, 1903, is recorded, its male described and illustrated from specimens collected from Seriolella violacea and Trachurus murphy, taken in the same locality.  相似文献   
22.
《Journal of Natural History》2012,46(3-4):197-202
Thirteen Notostrix Keifer species are presently known, all from leaves of palm trees (Arecaceae) to which they seemingly cause no major damage. A new species of this genus, Notostrix macrothrix sp. nov., is morphologically described based on adult females and males collected from coconut, Cocos nucifera L. (Arecaceae), on La Reunión Island. A discussion about the presently known distribution of mites of this genus is also presented. http://www.zoobank.org/urn:lsid:zoobank.org:pub:14C65CB2-AF56-4D85-AD49-56FA11119EF5  相似文献   
23.
《Journal of Natural History》2012,46(9):1047-1103
A total of 101 verified species and eight ordinal taxa represent the non-marine Crustacea on Antarctica and the islands of the Southern Ocean. The largely terrestrial Isopoda and Amphipoda are confined to some sub-Antarctic and cool temperate islands while the predominantly freshwater Anostraca, Anomopoda, Copepoda (=Calanoida, Cyclopoida, Harpacticoida) and Ostracoda (Podocopida) occur throughout the region. Holocene sea-level rises fragmented freshwater and terrestrial species ranges on New Zealand, Auckland, Campbell, and possibly other South Pacific islands, leaving a legacy of vicariant taxa. Tertiary species probably survived Pleistocene glaciation in aquatic refugia on the New Zealand/South Pacific, Falkland, Crozet and Kerguelen archipelagoes, but there are no valid records of Tertiary Antarctic Crustacea. All 40 Continental and Maritime Antarctic freshwater records can be ascribed to the historic introduction of anthropogenic aliens, Holocene immigration of colonists, returning re-colonists and marine species 'marooned' in epishelf and other coastal lakes.  相似文献   
24.
为了獐子岛海域虾夷扇贝养殖容量评估模型的建立,采用模拟现场流水系统和生物沉积方法测定了不同规格虾夷扇贝在不同季节的滤水率(CR)、摄食率和吸收效率,并探讨了温度与滤水率的关系.通过断面生物量调查,获得该海域虾夷扇贝的壳高频率分布情况.结果显示,5月份虾夷扇贝的滤水率最大.其它3个月份虾夷扇贝的滤水率差异不显著,10月份的吸收效率最低.温度(T)与滤水率(CR)呈抛物线的关系,在本实验的条件下,虾夷扇贝摄食的最适温度为10 ℃.滤水率与壳高呈典型的幂函数关系.根据滤水率与壳高的关系、獐子岛海域养殖虾夷扇贝的壳高频率分布情况以及总生物量,推算出不同月份的群体滤水能力,结合獐子岛的潮差、水面面积等数据,计算出其在该海域的食物限制性指标--清滤效率.结果显示:目前獐子岛养殖虾夷扇贝的清滤效率平均为0.054<1,虾夷扇贝的养殖量低于养殖容量,在养殖密度和规模上,尚有很大的发展空间.  相似文献   
25.
《Journal of Natural History》2012,46(17):2119-2149
Surveys of the amphibians and reptiles on Nosy Be (an island off north-west Madagascar) and nearby islands were undertaken between 1991 and 2001 and are discussed here in view of biodiversity considerations and conservation efforts. Since Nosy Be is the type locality of several amphibian and reptile taxa, their exact status is of crucial importance for the nomenclatural stability of many groups of the Madagascan herpetofauna. A total of 20 amphibian and 61 reptile species (excluding marine reptiles) was confirmed for this archipelago. Other species (Mantidactylus horridus, Androngo elongatus, Typhlops madagascariensis, T. reuteri, Micropisthodon ochraceus and Pararhadinea melanogaster) were not found during these inventories, but are quoted in the literature or housed in herpetological collections, and are considered as likely to be present at Nosy Be. A further 18 taxa are tentatively excluded from its fauna, due to biogeographic incongruence and/or lack of reliable voucher specimens. Few taxa are so far only known from the island; they may represent endemics or may have been overlooked on the adjacent mainland. They are respectively Stumpffia pygmaea, Mabuya lavarambo, Lygodactylus h. heterurus, Lycodryas granuliceps and Typhlops reuteri. Heterixalus tricolor too is likely to be present on Nosy Be only, but the difference with respect to taxa present on the mainland needs to be confirmed. Several species are known from nearby islands and islets surveyed (11 amphibians and 26 reptiles). A few of them (Heterixalus 'variabilis', Kinixys belliana, Furcifer oustaleti, Mabuya comorensis, Paracontias milloti) are present on some of these islands but have not yet been found on Nosy Be. Much of the field research was conducted at Lokobe, a strict nature reserve still characterized by good forest coverage (typical of the Sambirano Domain), and an important area of biodiversity. With 15 amphibian and 45 reptile species, Lokobe hosts 81% of the overall Nosy Be herpetofauna: of the species found during our surveys, only Heterixalus tricolor, Hoplobatrachus tigerinus, Gehyra mutilata, Phelsuma dubia and Crocodylus niloticus were only found outside the reserve. In view of this, the protection of Lokobe should be assured and reinforced. Except for Lokobe, habitats on Nosy Be are largely anthropogenic, and have a lower species diversity, especially where there is intensive agriculture. At other sites (e.g. ylang-ylang and coffee plantations) and in forested bands along roads, species diversity is still high: careful management of these anthropogenic habitats might also assure the survivorship and conservation of a diverse herpetofauna outside the protected area.  相似文献   
26.
海南万宁礼纪青梅林(续完)   总被引:2,自引:0,他引:2  
海南万宁礼纪青梅林(续完)梁淑群,林英,杨小波,黄世满,符史新,谢国干(海南大学)礼纪青皮林自然保护区植物名录面类植物门PTERIDOPHYTA1松叶蕨科Psilotaceae1)松叶蕨Psilotumnudum(Linn,)Griseb2水龙骨科P...  相似文献   
27.
海南岛的棕榈科藤本植物资源   总被引:1,自引:0,他引:1  
笔者对海南岛的棕榈科藤本植物资源进行了调查。海南岛分布有3属12种棕榈科藤本植物。这些植物资源中有5种是海南岛有发展前途的人工种植的藤种;有4种是海南岛的特有种。为有效地保护和发展海南岛的棕榈科藤本植物资源提供了科学的依据。  相似文献   
28.
本文对七星岛底栖海藻种类组成、区系特点、季节分布、经济种类等进行了描述和探讨。  相似文献   
29.
Although petroleum exploration is being conducted in the Hong Kong region, high-quality hydrocarbon source rocks have never been found in this area. The Ping Chau Formation is only Mesozoic-Cenozoic sedimentary rock exposed in Hong Kong and its surrounding areas. The hydrocarbon source rock of the Ping Chau Formation is very rich in organic matters, which has an average total organic carbon (TOC) of 1.9% and chloroform bitumen ““A““ range from 0.14% to 0.24%. The total hydrocarbon content varies from 880 to 1800 ppm and the transformation ratio is specific from 5 to 9. The index of pyrolytic hydrogen is up to about 600 mgHC/gTOC. These data demonstrate the characteristics of the high-quality hydrocarbon source rock. The lamalginite is the major maceral of the source rock of the Ping Chau Formation, and geochemical characteristics also suggest that the organic materials of the source rock are of type I and type Ⅱ1, with abundant gammacerane, γ, β-caro-tane and C24 tetracyclic terpane, which indicate that it was formed in the salt water and brackish water sedimentary environment, and the source rock has evolved into a mature phase. The organic inclusions are found within calcite veins in cracks of the source rock, indicating that hydrocarbon has been generated and a secondary migration has happened. The source rock in the Ping Chau Formation is about 200-300 m thick, thus having considerable hydrocarbon potential. The discovery of the high quality hydrocarbon source rock in the Ping Chau Formation will certainly provide insight on hydrocarbon resource exploration in the South China Sea area.  相似文献   
30.
本文根据东西连岛的区位和发展条件,确定了连岛的开发方向和总体规划布局,并对过岛的发展规模进行了预测.  相似文献   
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