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71.
浒苔(Enteromorpha prolifera)的分类鉴定、生境习性及分布   总被引:7,自引:0,他引:7  
结合过去的工作基础,对2008年5月底以来黄海西部沿海水域漂浮聚集的绿藻样品进行了分类学研究.经鉴定,其为绿藻门石莼目石莼科浒苔属的浒苔Enteromorphaprolifera,其主要分类鉴定特征为藻体暗绿色或亮绿色、管状扁压、中空、主枝明显、分枝较多、密集且细长.文中对其生境习性及其分布特征也作了较详细地介绍.  相似文献   
72.
Two new species of genus Ectopleura, i.e., Ectopleura elongata sp. nov. and E. triangularis sp. nov. are described in the present paper based on type specimens from the Taiwan Strait. The types are deposited in the Third Institute of Oceanography, State Oceanic Administration, Xiamen, China.  相似文献   
73.
A new non-marine ostracod Mongolocypris kohi sp. nov. is described from the upper Lower Cretaceous Jinju Formation of the Gyeongsang Basin, South Korea. This new species was described as Cypridea (Pseudocypridina) spp. by previous authors, but the typical rostrum shape, inconspicuous alveolar notch, the lack of alveolar ridge and the elongate limen are features that this species has in common with the genus Mongolocypris Szczechura, 1978. M. kohi sp. nov. is characterized by a reduced rostrum, the presence of a faint alveolar furrow and a slightly curved limen. This new species is considered an ‘early form’ of the genus Mongolocypris by its reduced rostrum and the faint alveolar furrow.  相似文献   
74.
The reliability of the first appearance datum of Globotruncana ventricosa as biozonal marker for the Campanian is discussed. The taxonomy and species concept of G. ventricosa and of Globotruncana tricarinata, that has been either regarded as junior synonym of Globotruncana linneiana or of G. ventricosa, are examined to avoid misidentifications, and one species is here formally described as new, Globotruncana neotricarinata nov. sp. The tropical and subtropical planktic foraminiferal assemblages from the Bottaccione section (Gubbio, Italy), from Deep Sea Drillig Project (DSDP) Site 146 (Caribbean Sea, central Atlantic Ocean), and from Ocean Drilling Program (ODP) Hole 1210B (Shatsky Rise, northwestern Pacific Ocean) are analyzed for the presence of biostratigraphic markers. Lowest and highest occurrence data have been checked in thin sections and washed residues in the Bottaccione section. The comparative biostratigraphic analysis of the planktic foraminiferal distribution highlights: 1) the absence of G. ventricosa at the stratigraphic level at which it is supposed to first occur in the Tethyan area, 2) the presence of transitional specimens resembling G. ventricosa and thus erroneously used to identify the base of the G. ventricosa Zone, 3) the presence of a good sequence of bioevents that appear to be promising for regional and global correlations such as the appearance of Globotruncanita atlantica, Contusotruncana plummerae and the disappearance of Hendersonites carinatus. The correlation potential of these bioevents has been verified across latitudes by studying the Campanian planktic foraminiferal assemblage in pelagic sediments drilled on coastal Tanzania (western Indian Ocean), and at the deep-sea ODP Hole 762C (Exmouth Plateau, western Indian Ocean), that were located at 30°S and 47°S in the Late Cretaceous, respectively. Besides the known diachronous first appearance of G. ventricosa in the Southern Ocean sites, results confirm the difficulty in using G. ventricosa as zonal marker in the tropical and subtropical areas, and the validity of the first appearance datum of C. plummerae for regional and global correlations.  相似文献   
75.
The genus Debrunia is characterized by its myophoral organisation: the left valve posterior myophore is an erect plate, the anterior is a bulge or a crest, myophores of right valve are on shell wall, the ligament groove is inconspicuous and the cardinal apparatus tends to be shifted posteriorly. Shell habit varies from low conical to elongated cylindrical, and the shape of the left valve ranges from capuloid to flat. The taxonomic revision of Debrunia species of the Mediterranean regions reveals the presence of thirteen species, among which seven are described as new. Multiple Component Analysis and Cluster Analysis document the existence of five groups of species in correspondence with the height of the left valve and the commissural diameter. The longevity of Debrunia is high, 32 Myr, whereas its species have shorter durations which account for a significant biostratigraphic potential within the Valanginian–Albian time span. Debrunia has its FO (First occurrence) in the lower Valanginian and its LO (Last occurrence) in the Albian. Its developmental phase starts in the Hauterivian, marked by an increasing species diversity and a biogeographic expansion; and peaks in the late Barremian, followed by a collapse in diversity and a specific turnover, coeval with the “Agriopleura extinction event”. The mid-Aptian crisis is expressed by a drastic decline in species diversity, controlled by the overall restriction or demise of carbonate platforms in European regions. As elevators, Debrunia species tend to build dense monospecific aggregations and some of them possess a remarkable bioconstructional potential. The contribution of Debrunia to rudist communities is significant throughout the history of the genus.  相似文献   
76.
New fossil genus with a new species, Stellularis longirostris Chen, Yao and Ren, gen. et sp. nov., from the family Procercopidae, are described. New specimens were collected from the Lower Cretaceous non-marine sedimentary strata from the Yixian Formations of northeast China. The exceptionally well-preserved materials reveal fine details of the body structure and morphology including rostrum, legs, abdomen, anteclypeus and ovipositor. The genera Luanpingia Hong, 1983 and Cathaycixius Ren, Lu, and Guo, 1995 are discussed.  相似文献   
77.
对作者于1998~2003年间在中国沿海采集的褐毛藻属 Halothrix 标本进行了分类研究。经鉴定,确认有4个种,即可疑褐毛藻H. ambigua Yamada、细弱褐毛藻H. gracilis Luan et Ding sp. nov.、褐毛藻 H. lumbricalis (Kuetzing) Reinke和垫状褐毛藻 H. pulvinata Luan et Ding sp. nov.,其中新种2个。文中对这4个种进行了较详细的特征描述,以及较完整的其他分类学信息,并编制了检索表。细弱褐毛藻H. gracilis Luan et Ding sp. nov.的长同化丝稍细,直径15~55μm,中、上部细胞较长,长宽比为1.3~3;短同化丝的细胞较多,10~17个;具有匍匐丝体。垫状褐毛藻 H. pulvinata Luan et Ding sp. nov.具有明显垫状的基部,由多数无色丝体组成,丝体细胞13~20个,细胞长宽比为1.3~11,长同化丝在基部多分枝。其研究结果在一定程度上丰富了我国大型海藻的物种多样性。模式标本保存在中国科学院海洋研究所海洋生物标本馆(AST)。  相似文献   
78.
Two new species of wasps belonging to the family Ephialtitidae,Praeproapocritusflexus sp.nov.and Proapocritus parallelus sp.nov.,from the Middle Jurassic Jiulongshan Formation of southeastern Inner Mongolia,China,are described and illustrated.Praeproapocritus vulgates Rasnitsyn & Zhang,2010 and six species of Proapocritus,P.densipediculus,P.sculptus,P.longantennatus,P.formosus,P.atropus,and P.elegans,all described by Rasnitsyn and Zhang in 2010,are first record from the Middle Jurassic of China.These two new findings supplement the morphological understanding of ephialtitids in the Middle Jurassic of China and broaden the diversity of ephialtitids in their by-gone ecosystems.  相似文献   
79.
An early Berriasian (Berriasella jacobi Zone) ammonite fauna is described for the first time from the Alborz Mountains in northwest Iran. It has been collected from a section located near the village of Shal (Talesh region); in addition to rare phylloceratids, lytoceratids and Neolissoceras, the majority of ammonites belong to the neocomitid subfamily Berriasellinae. With the exception of a new genus and species, Taleshites fuersichi, these taxa are common in European and North African Tethyan successions. Associated calpionellids confirm the early Berriasian age of the ammonite-bearing levels.  相似文献   
80.
This paper and a companion article present illustrated guides to the identification of sub-fossil chironomid larvae (Insecta: Diptera: Chironomidae) preserved in the sediments of low- and mid-elevation lakes in East Africa. They are based on analysis of surface-sediment death assemblages from 61 lakes located in the humid to semi-arid environments of equatorial East Africa (Uganda, Kenya, Tanzania), supplemented with similar surface-sediment samples from 12 lakes in the Horn of Africa (Ethiopia), and sub-recent core samples from six lakes in Kenya and two in Uganda. We analyzed about 11,000 specimens and identified 98.4% of these to species, species group, genus, or tribe level depending on current -taxonomic knowledge of the various genera considered and the taxonomic resolution of preserved diagnostic features. We distinguished 90 different sub-fossil morphotypes, of which 16 are Tanypodinae, 19 are Orthocladiinae, and 55 are Chironominae. Diagnostic characters distinguishing these morphotypes from each other resemble differences at the species level in the better-known Holarctic fauna, hence we consider most of our morphotypes equivalent to morphological species or groups of closely related species. In this paper we focus on the Tanypodinae and Orthocladiinae, with special attention to the high taxon richness among the Pentaneurini. Patterns of cephalic setation were found to facilitate identification of Tanypodinae both at the genus and species level, and contributed to improved taxonomic resolution in sub-fossil East African material. High taxon richness and numerical abundance of the Orthocladiinae in our study lakes indicates that a considerable number of African Orthocladiinae is adapted to warm standing-water environments.  相似文献   
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