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81.
This review of the literature shows that amphipod crustaceans create disturbance through predation on commercial harvests, attacks on macroalgae, introductions as exotic species, and interference competition. Amphipods are also affected by disturbance events, both man-made and natural. Anthropogenic disturbance includes environmental alteration by toxins, oil, organic enrichment, acidification, salinity alteration, and ships' wakes. Natural disturbances are space clearance by the feeding activities of other fauna, and physical disturbance by sediment erosion and ice scour.  相似文献   
82.
83.
《Journal of Natural History》2012,46(6):1419-1445
Seventeen species of Tardigrada from lakes and catchments on Signy Island, South Orkney Islands, are described. Two species, Echiniscus punctus and Isohypsibius laevis are new to science, and two, Oreella minor and Pseudechiniscus suillus, are new to the Signy Is. records.  相似文献   
84.
报道了安徽省2新分布记录种,分别为大戟科的山靛(Mercurialis leiocarpaSieb.et Zucc.)和齿裂大戟(Euphorbia dentata Michx.).该两种植物均具有一定的毒性,后者原产于美洲,为我国的入侵检疫物种,现在安徽黄山的山岔村、池州的江家冲附近发现有较大面积的分布,应予以关注.  相似文献   
85.
《Journal of Natural History》2012,46(6):1413-1419
Didogobius schlieweni sp. nov. is described from a single specimen collected among pebbles in shallow water at Unije island, near Cres, in the northern Adriatic Sea. The holotype has vivid dark and pale patterning, and is assigned to Didogobius on the basis of head neuromast patterns and meristic features. Diagnostic values of the latter are D2 I/12, A I/11, P 17, and LL 55–56. A key to species of the Chromogobius and Didogobius complex is provided.  相似文献   
86.
《Journal of Natural History》2012,46(6):1325-1331
A new genus of Conchaspididae, Asceloconchaspis gen. nov., is described for Asceloconchaspis milleri sp. nov., a new species from Florida, USA. Unlike other conchaspidids, the adult female and second instar of the genus lack legs. The presence of legs is one of the important, distinguishing characters at present separating the Conchaspididae from the Diaspididae. However, the new genus also possesses well-developed antennae and has multilocular disc pores on the abdomen in the adult female; these distinctly conchaspidid characters are never found in the Diaspididae. Asceloconchaspis is closely related to Fagisuga Lindinger, a monotypic genus with primitive characters described from South America on Nothofagus. A key to the four known genera of Conchaspididae is provided, and the morphology and distribution of the Conchaspididae are discussed.  相似文献   
87.
The order Misophrioida is recorded for the first time in Brazilian waters and the new species Archimisophria squamosa, with some important plesiomorphic features, is described.  相似文献   
88.
Summary

On investigation of a dense population of mud tube building polychaetes tentatively identified as Polydora ciliata it was found that many individuals also showed morphological characteristics more usually associated with other members of the same genus. This prompted the examination of the morphology of P. ciliata from a number of different areas with the aim of assessing the stability of some of the characters used in the taxonomy of its genus. These proved to be highly variable, did not group together consistently and overlapped with some of those of P. limicola (Annenkova) and P. ligni Webster. No clear distinction between P. ciliata and P. limicola could be made on the grounds of the characteristics examined but the overlap between P. ciliata and P. ligni was small.  相似文献   
89.
A new species under the name Scaptognathus ventridiscus sp. nov. is described from Japan. It differs from its congeners by the possession of a ventral disc in the male, a peculiar arrangement of dorsal plates and dorsal setae, and unique leg chaetotaxy.  相似文献   
90.
Eustigmaeus floridensis sp. nov. is described and illustrated based on female specimens collected from citrus trees in Florida, USA. The new species is closely related to Eustigmaeus arcuata, Eustigmaeus segnis and Eustigmaeus microsegnis, all known to occur in Florida. Eustigmaeus floridensis sp. nov. can be distinguished by larger dimples associated with setae sce, d2 and e1 containing at least four or more vacuoles centrally; dorsal body setae broadly lanceolate and feather-like, except c2, which is slender; anogenital area with striae and one pair of serrated aggenital (ag1) and three pairs of serrated pseudanal (ps1?3) setae. A key to the Eustigmaeus species known to occur across USA is also provided.  相似文献   
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