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Ataxonomic survey of benthic marine animals from coastal regions of Hainan Island, South China Sea, revealed specimens of a new species of Eunice (Polychaeta: Eunicida: Eunicidae), Eunice uschakovi n. sp., collected from the intertidal zone. The species belongs to the group of Eunice that has yellow tridentate subacicular hooks and branchiae scattered over an extensive region of the body. It resembles E. miurai and E. havaica in having both bidentate and tridentate falcigers, but can be readily distinguished by branchial features. Comparisons between E. uschakovi and the two related species are presented. 相似文献
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基于中国科学院海洋生物标本馆历年收藏的标本对明管虫属开展了分类学研究，共发现两种明管虫：Hyalinoecia tubicola （Müller，1776）（明管虫）和H.papillata Imajima，1999（乳突明管虫）。二者均采集于南海北部海域沙质基底，Hyalinoecia tubicola广泛分布于广东省沿岸海域向南至西沙群岛，H.papillata则首次报道于中国南海，其区别于H.tubicola在于第一疣足具伸长舌状、两侧边缘具有乳突的前刚叶（ vs.耳状前刚叶、边缘光滑）。本文详细提供了二者的形态学描述和绘图。 相似文献
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Abstract. Important intertidal sabellarian reefs are built by the polychaete Sabellaria alveolata (LINNÉ ) in the Mont Saint-Michel Bay in Normandy at Champeaux (France). Typical profiles and plans were done over a ten year period. At the same time, population dynamics were examined during the last six years. At this site a nearly complete morphological cycle spread itself over more than ten years. Initially built on rock substrate (primary settlement phase), the studied reefs actually lie on a sandy shore. The growth phase begins by stages of balls which are then joined with new settlements between or on older tubes (secondary settlement). This phase comes to an end with an important platform stage. Then, the destruction phase brings us back to dead eroded reefs on which new worms can settle (secondary settlement). This cycle seems to be independent of the age of the living population, although new settlements of young worms and also sufficient hydrodynamics seem necessary. 相似文献
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Abstract. During a 12-month period (from May 2000 to the end of April 2001), the reproductive activity of three Exogoninae species was studied: Grubeosyllis clavata (Claparède, 1868), G. vieitezi (San Martín, 1984) and Sphaerosyllis (Sphaerosyllis) hystrix Claparède, 1863. A sample consisting of two replicates was collected every second month, and the individuals of each species were counted and assigned to different reproductive categories (immature, mature, and bearing eggs or embryos). The populations of the three species showed a dramatic decline in numbers during summer 2000. In regard to the reproductive activity, the two species of Grubeosyllis showed a continuous activity during the whole year, with a peak in July for G. vieitezi and in September and November for G. clavata . In contrast, S. (S.) hystrix had a pause in its reproductive activity in late summer when no mature or offspring-carrying specimens were found. A relationship between the reproductive cycle and the brooding type (dorsal eggs versus ventral embryos) is likely, although further studies on other exogonin species are necessary to confirm the hypothesis suggested by the present results. 相似文献
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Gary R. Gaston 《Estuarine, Coastal and Shelf Science》1985,20(5):603-613
The effects of hypoxic bottom water, an annual event, were documented on the inner shelf off Cameron, Louisiana during the summer of 1981. Populations of most species of macrobenthos were dramatically reduced. In an area of fine sediment that was numerically dominated by polychaetous annelids, the most severely affected populations were those of tube-dwelling and surface-feeding species. Burrowing species were less influenced by the hypoxia. 相似文献
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Abstract. Population dynamics and secondary somatic production data of a population of the polychaete Hediste diversicolor (O. F. Müller) are reported. Monthly samples were taken in a small muddy-sand flat in the Gernika estuary (Basque Country, North Iberian Peninsula) from May 1991 to May 1992. In addition to H. diversicolor abundance, temporal variation of the infauna and sediment conditions were analysed. Size measurements were employed to estimate H. diversicolor biomass and several cohorts were differentiated based on the size distribution. Secondary production was estimated based on cohort summation of growth increments following individual cohorts through time. Results are compared with those of other H. diversicolor populations located along the whole latitudinal gradient of distribution of the species. 相似文献
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Platynereis dumerilii is found in large numbers in parchment-like tubes attached to sublittoral accumulations of detached maroalgae (principally Laminaria saccharina) in Kames Bay, Isle of Cumbrae and Lochranza, Isle of Arran. Its rôle in weed decomposition has been examined by comparing its responses (behavioural choice, growth rates, absorption efficiencies of both carbon and protein, gut retention times and rate of faecal output) to fresh and rotting weed. Worms grew significantly on either diet, with older individuals gaining more weight than small individuals. Animals of a standard size (derived from measurements of maximum bite size) feeding on fresh weed, however, grew significantly faster than those feeding on rotting weed. The former had a significantly higher protein absorption efficiency which was linearly related to protein content of ingested weed. This was not so on rotting weed. Organic carbon absorption efficiencies did not differ significantly between the two groups, neither did gut retention times nor rates of faecal output. Given a choice, Platynereis chooses to build its tube, and to feed, on fresh kelp—a strategem which ensures both maximum scope for occupancy before fronds decay and a superabundance of preferred food. Platynereis feeds around its tube entrance, recropping small areas for 2–3 days, prior to switching to another area nearby. Ciliate population densities on Platynereis faeces are much lower than on either homogenized or intact weed, associated with their lower, nutritional value (at first). Platynereis bubes act to bind kelp fronds together stabilizing the faecal input to infaunal detritivores. Platynereis is an example of a detritivore which exploits the detrital substratum directly. 相似文献
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