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71.
《Journal of Natural History》2012,46(19-20):1179-1218
This paper deals with some of the Amphipoda Maeridae and Melitidae, i.e. one species in the genus Dulichiella and two in Elasmopus, collected during the Hourglass cruises, a 28-month sampling programme at 10 stations (5–73 m depth) on the central West Florida shelf. A key to world Elasmopus species is provided.  相似文献   
72.
利用来自欧洲中期天气预报中心(ECMWF——European Centre for Medium-Range Weather Forecasts)的长时间序列、高精度的ERA-40海表10 m风场资料,对北大西洋海域海表风场的季节特征、长期变化趋势进行深入研究,研究发现:(1)北大西洋海域的海表风速等值线在各季均大致呈东西带状分布,且由高纬度向赤道表现出高—低—高—低的分布特征。MAM和SON期间海表风速的分布特征较为相似,大值中心分布于北半球西风带海域;DJF期间的海表风速为全年最大;JJA期间的海表风速为全年最小。加勒比海海域常年存在一风速的相对大值中心。从多年平均来看,风速存在一明显的、范围较广的大值区:西风带海域,加勒比海也存在一范围较小的大风区。(2)1958年至2001年期间,北大西洋海域的海表风速以0.0049 m.s-1.a-1的速度显著性逐年线性递增。(3)北大西洋海表风速的变化趋势表现出较大的区域性差异:呈显著性逐年线性递增的区域主要分布于30°N以下的低纬度海域,变化趋势在0.01~0.025 m.s-1.a-1左右,西班牙东北部近海的递增趋势最为强劲,达到0.035 m.s-1.a-1以上,墨西哥湾和加勒比海则呈显著性逐年线性递减,趋势为-0.015 m.s-1.a-1左右,其余海域的海表风速无显著变化趋势。(4)近44年期间,北大西洋海域的海表风速存在明显的突变现象,突变期为1972年前后。  相似文献   
73.
南大西洋、南印度洋冷空气活动的统计分析   总被引:2,自引:0,他引:2       下载免费PDF全文
采用 NCEP1 995~ 1 997年逐日 2 .5°× 2 .5°经纬网格点再分析资料 ,统计分析了 70 0 h Pa逐日 2 4 h变温分布和演变特征 ,讨论了影响南大西洋、南印度洋冷空气源地、路径和季节变化特征 ,以及冷空气活动与大气环流背景之间的关系 ,提出了影响南大西洋和南印度洋冷空气活动的天气过程模型  相似文献   
74.
75.
The multi-spatial variability modes of the Atlantic Meridional Overturning Circulation (MOC) are identified in the natural coupled simulation of two climate models, the MOC either oscillates at decadal scales with strong cross- equatorial flow or fluctuates locally at interannual scales with weaker cross-equatorial flow. Former studies mainly emphasize the paleo-environmental and paleo-climatic impacts of the meridional overturning states transition; this analysis indicates the existence of the multi-spatial variability modes of the MOC at interannual to decadal scales. Further analysis indicates that the conventionally used MOC index, which is defined as the maximum zonal mean meridional stream-function of the North Atlantic, cannot properly describe the multi-spatial variability characteristics of the MOC.  相似文献   
76.
In this paper, material belonging to the genus Schizomavella, collected along the Croatian coast of the Adriatic Sea, is revised. Nine species were identified, including five species new to science: S. cornuta, S. halimedae, S. linearis, S. mamillata, S. adriatica sp. nov.,S. mystacea sp. nov., S. rosae sp. nov., S. stanislavi sp. nov. and S. tubulata sp. nov. Previous records of Schizomavella from the Adriatic are also discussed. The checklist of Adriatic Schizomavella species is updated to 11 species; a further two species are doubtful owing to wrong previous identifications. The presence of a calcified ‘hood’ covering the opesia of the suboral avicularium is described and its function is discussed. The morphological diversity of ovicells within the genus Schizomavella is compiled and discussed.

http://zoobank.org/urn:lsid:zoobank.org:pub:987D8AE0-1E02-430D-9AB5-50B77BEAF52E  相似文献   

77.
78.
Until recently, Calanoides carinatus s.l. was assumed to be very widespread in the upwelling systems of the Atlantic, Indian and western Pacific Oceans. Molecular data, reported here, show that Calanoides from the eastern Atlantic and Arabian Sea are one species and distinct from C. carinatus s.s. The name Calanoides natalis Brady, 1914 is available for this species, which is fully re-described. The illustration by Brady of the male fifth leg and the currently reported genetic data lead us to conclude that C. natalis is distributed from the Bay of Biscay southwards along the eastern Atlantic, around the Cape of Good Hope, and northwards along the western boundary of the Indian Ocean as far as the Arabian Sea. A by-product of this study is the recognition that Calanoides macrocarinatus is a junior synonym of Calanoides brevicornis. Females of C. natalis are easy to distinguish morphologically from C. carinatus s.s. but are more similar to C. brevicornis, apart from size differences. From physical oceanographic evidence we conclude that the Indian Ocean is currently the upstream part of the distribution of C. natalis. Calanoides philippinensis is known to extend into the eastern Indian Ocean at tropical latitudes. It is not known if it is C. philippinensis that has been recorded along the western coast of Australia. An apparently undescribed species of Calanoides occurs on the eastern Australian coast.  相似文献   
79.
《Journal of Natural History》2012,46(13):1591-1604
The life cycle of the gymnophallid Bartolius pierrei Cremonte, 2001 Cremonte, F. 2001. Bartolius pierrei n. g. n. sp. (Digenea: Gymnophallidae) from Península Valdés, Argentina. Systematic Parasitology, 49: 139147. [Crossref], [PubMed], [Web of Science ®] [Google Scholar] (Digenea) at Fracasso Beach (the type locality) (42°25′S, 64°07′W), Península Valdés, Argentina, was elucidated. This digenean uses the clam Darina solenoides (Mactridae) as both first and second intermediate host. The Kelp Gull, Larus dominicanus, and the Red Knot, Calidris canutus rufa, a Neotropical migratory bird, act as definitive hosts. A prevalence of infection of 92% was found in the Red Knot. The cercariae of B. pierrei did not parasitize other invertebrates, not even the tellinid clam Tellina petitiana, which shares the intertidal habitat with D. solenoides. This fact could be explained by the behaviour of the cercaria and its strategy for penetration. The cercariae enter directly in the extrapallial space of the clam by piercing the exposed mantle border. Tellina petitiana could not be invaded by B. pierrei cercariae because it does not expose the mantle border when feeding. Because the Red Knot does not feed on T. petitiana, this behaviour may constitute an adaptive strategy of the parasite. Under laboratory conditions, cercariae lived up to 2 days, metacercariae became infective in 50 days, and the adult life is considerd to be shorter than 3 days. The short adult life span in gymnophallids could be a result of adaptation to migratory birds. This fact would ensure parasite dispersion (i.e. by covering long distances in a short time) and inter-breeding with other Darina-infesting populations located far apart. Bartolius pierrei is an endemic parasite of the Magellan Region, distributed where its intermediate clam host is present, from San José Gulf in Península Valdés to the southern tip of South America.  相似文献   
80.
《Journal of Natural History》2012,46(19-20):1209-1246
ABSTRACT

A genus of small, yellow mimallonid moths, Zaphanta Dyar, is revised. This genus has been shown to be sister to the remainder of Mimallonidae, and therefore has been placed in its own monogeneric subfamily, Zaphantinae St Laurent and Kawahara. Long considered monotypic or bitypic, Zaphanta have not been the focus of any systematic treatment. The moths belonging to this genus are found throughout Central and South America, and detailed examination of several disparate, as well as sympatric, populations of Zaphanta have revealed numerous undescribed species all of similar appearance, but with distinct male genitalia, which we describe here. We redescribe Z. infantilis Dyar and Z. fraterna Schaus, and describe the females of both for the first time. An additional nine new species are described and figured from the Amazon, Cerrado and Atlantic Forest: Z. acuta sp. nov., Z. anas sp. nov., Z. bahiana sp. nov., Z. beckeri sp. nov., Z. elephanta sp. nov., Z. elephanticula sp. nov., Z. machaera sp. nov., Z. rawlinsi sp. nov. and Z. stiletto sp. nov. One of these, Z. beckeri, may be extremely imperilled due to deforestation.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:B45DDB85-977F-42EF-9F2F-DB48827E521Ehttp://www.zoobank.org/urn:lsid:zoobank.org:act:C6F7DBF4-4871-403D-A387-DD920BA76D8Bhttp://www.zoobank.org/urn:lsid:zoobank.org:act:C4C8DAAF-8C60-4C16-A626-3641EA3817FBhttp://www.zoobank.org/urn:lsid:zoobank.org:act:6A57E1CC-D3E5-4E45-8C82-7006295ADF1Fhttp://www.zoobank.org/urn:lsid:zoobank.org:act:03241157-1925-4EF6-B426-A8E816C7E457http://www.zoobank.org/urn:lsid:zoobank.org:act:A00749E5-888C-45FB-8FAA-0302A402496Fhttp://www.zoobank.org/urn:lsid:zoobank.org:act:89132977-91DC-4424-9C0E-98A954E467CAhttp://www.zoobank.org/urn:lsid:zoobank.org:act:11AA3541-C7A4-4292-A5CA-10B89C5FAD2Chttp://www.zoobank.org/urn:lsid:zoobank.org:act:A5FA3ED1-5994-46B4-B018-1FA055C76496http://www.zoobank.org/urn:lsid:zoobank.org:act:F1C63621-EF30-40B1-B437-87A79BD7E339  相似文献   
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