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基于壳板和齿舌形态对中国沿岸几种常见多板纲软体动物的分类研究 总被引：1，自引：1，他引：0
多板纲软体动物统称石鳖,是软体动物门较为低等的一个类群,在软体动物的系统进化中占有重要的地位。但有关我国沿海多板纲软体动物的调查研究十分欠缺,而且对中国沿海多板纲的分布状况和区系特点尚不明确,并存在着一些鉴定错误和分类混乱现象。本研究利用10%Na OH溶液处理齿舌部获取齿舌带和壳板的方法,通过扫描电镜和显微镜观察拍照,对我国沿岸常见多板纲软体动物中5科7属13种的齿舌和壳板形态结构进行了描述,并进行了比较研究。 相似文献
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R. C. Murdoch 《新西兰海洋与淡水研究杂志》2013,47(2):175-178
Plaxiphora boydeni n.sp. from wave‐exposed rocky shores of southern New Zealand is described and illustrated. This is the first published record of the genus from the New Zealand mainland. P. boydeni is readily distinguished from the 2 other New Zealand species of the genus, which occur in the subantarctic region, by the absence of bristle‐tufts on the girdle. 相似文献
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Melisa P. CHARó Gisela D. CHARó Guillermo ACE?OLAZA Jose L. CAVALLOTTO 《《地质学报》英文版》2022,96(4):1181-1198
The Late Pleistocene littoral ridges of southern South America, especially those of the north of Argentinean Patagonia, contain remains of mollusk shells with bioerosion traces. Eleven sites from marine isotope stages (2 from MIS 7, 4 from MIS 5e) and five sites from modern beaches from northern Río Negro Province, with 40 taxa (17 bivalves and 23 gastropods) were analyzed, in the area between west of Baliza San Matías and Las Grutas (41°S). Three ichnogenera were identified in deposits of MIS 7: Entobia, Gastrochaenolites (Domichnia) and Oichnus (Praedichnia) with one ichnospecies (G. torpedo). Six ichnogenera were identified in deposits of MIS 5e: Entobia, Meandropolydora, Pinaceocladichnus, Iramena, Caulostrepsis and Oichnus with one ichnospecies (O. simplex). Seven ichnogenera were identified from modern beaches: Entobia, Meandropolydora, Iramena, Caulostrepsis, Pinaceocladichnus, Gastrochaenolites (Domichnia) and Oichnus (Praedicnia), with two ichnospecies (O. simplex and O. paraboloides). On this basis, it is inferred that Pleistocene benthic communities were constituted from cheilostome bryzoans and polychaete annelids, together with drilling bivalves, predatory gastropods and overall warm-water species of mollusks. Of these, Chama iudicai was found on Plicatula gibbosa from MIS 7 and MIS 5e. The record of warm temperature species suggests a higher sea surface temperature (SST) than the present one and/or the influence of the warm southward Brazilian Current affecting the waters of Golfo San Matías. On the modern beaches surveyed, there is an increase in polychaete annelids, cheilostome bryzoans, temperate-cold species and drilling bivalves, as well as sandy substrate species, which together with an increase of Gastrochaenolites and Caulostrepsis, suggest a colder climate due to the greater influence of the Malvinas Current during the Holocene. 相似文献
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Comparative phylogeography and population genetic structure of three widespread mollusc species in the Mediterranean and near Atlantic 
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下载免费PDF全文 Although several studies have evaluated the genetic structure and phylogeographic patterns in many species of marine invertebrates, a general model that applies to all of them remains elusive. For example, some species present an admixture of populations with high gene flow, whereas others exhibit more complex patterns characterized by small‐scale unstructured genetic heterogeneity, even at a local scale. These differences are thought to be due to clear biological aspects such as direct versus indirect development, or the presence of lecithotrophic versus planktotrophic larvae, but few studies compare animals with similar distributions and life modes. Here, we explore the phylogeographic and genetic structure patterns in two chiton (Chiton olivaceus and Lepidopleurus cajetanus) and one abalone (Haliotis tuberculata) species co‐occurring in the same habitat. Samples were obtained from shallow rocky bottoms along the Iberian Peninsula (Atlantic and Mediterranean coasts), Italy, Croatia and Greece, and the mitochondrial markers COI and 16S rRNA gene were sequenced. Our data show evidence of admixture and population expansion in C. olivaceus and H. tuberculata, whereas L. cajetanus exhibited a ‘chaotic patchiness’ pattern defined by a high genetic variability with locality‐exclusive haplotypes, high genetic divergence, and a lack of geographic structure. Shared haplotypes were sampled in both coasts of Iberia (for H. tuberculata) and in the Western and Eastern Mediterranean (for C. olivaceus), potentially indicating high dispersal ability and a recent expansion. The processes underlying the fine‐scale structuring in L. cajetanus remain a mystery. These results are especially interesting because the reproductive mode of the two chitons is similar but differs from that of the abalone, with a veliger larva, while instead the genetic structure of C. olivaceus and H. tuberculata are similar, thus contrasting with predictions based on the life history of the three molluscs and showing that the genetic patterns of marine species may be shaped by many factors, including historical ones. 相似文献
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Vanessa Mendonça Catarina Vinagre Henrique Cabral Ana C. F. Silva 《Marine Ecology》2015,36(4):1098-1106
This study presents a new approach to examining European chiton habitat use according to morphological characteristics. Time‐search transects were conducted on four Portuguese rocky shores at two shore levels. The chiton species, abundance and individual morphometric features were recorded and related to the substratum dominant epiphytes and surface roughness. The chiton Lepidochitona cinerea (Linnaeus 1767) was the dominant species (77%), followed by Leptochiton algesirensis (Capellini 1859) (15%) and Acanthochitona crinita (Pennant 1777) (8%). Species abundance did not vary significantly with shore level or amongst shores. Six colour morphs were considered for Lepidochitona cinerea, four for A. crinita and one for Lepidochiton algesirensis. Substratum characteristics significantly explained the variation in species and colour morph distribution. There was a high correlation between the presence/absence and type of epiphytic algae and the substratum surface roughness level. We hypothesize that three mechanisms operating either independently or in interaction may explain the non‐random distribution of colour polymorphisms according to their habitat characteristics: (i) presence of algae that are part of their diet; (ii) use of rock as shelter – for instance, crevices and cover resulting from algae fronds and; (iii) morph–rock colour matching as a camouflage mechanism to reduce predation pressure. 相似文献
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