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1.
A new species,Clathrocorys gracilis nov. spec. of Tripocyrtidae (Radiolarians: Nassellaria) from surface water in northern South China Sea, is described in this
paper. The new species has four radial beams arising from the cephalic base centre, each foot with cup-shaped structure and
ramified bar in the proximal section (near cephalic base), and each wing with a large mesh in the middle, a medium mesh and
a small mesh on each side respectively.
Project supported by the NSFC (No. 40276044) and the Chinese Academy of Sciences (No. KSCX2-SW-101B). 相似文献
2.
Rony Huys 《Marine Ecology》1991,12(1):1-34
Abstract. Two new genera of Tantulocarida are described from the Ligurian deep sea (Western Mediterranean) off Corsica. Xenalytus scotophilia is referred to the Microdajidae and differs from Microdajus GREVE in thoracopodal segmentation as well as in the presence of coupling spines on thoracopod 6 and longitudinal lamellae on the cephalic shield. Aphotocentor styx is placed in the Deoterthridae and holds an intermediate position between Deoterthron BRADFORD & HEWITT and Boreotantulus HI/YS & BOXSHALL. Some aspects of cephalon internal structure are described for the first time and give a possible explanation for the mechanism of stylet protrusion. The external structures of the oral disc are described using SEM. The discovery of well-developed muscles in the trunk and thoracopods is discussed in the light of the benthic phase the tantulus passes through. The boundary between the thorax and abdomen in the tantulus is reinterpreted, corroborating the 5–7-5 bodyplan of the hypothetical urmaxillopodan as found in the Upper Cambrian Skaracarida and possibly also Dala peilertae MOLLER. Some aspects related to dispersal, infection, and feeding are reinterpreted or approached from a different perspective. SEM of Microdajus langi GREVE gives evidence that the tantuli hatch via a conspicuous slit located at the posterior end of the female trunk sac. A worldwide key to the tantulocaridan families and genera is given, and distributional records are compiled. It is suggested that Tantulocarida might be common representatives of the temporary meiobenthos and that their present species number represents only the tip of the iceberg. 相似文献
3.
4.
于1985-1986年在长江口的底栖生物取样中,采到大量双壳类软体动物标本。鉴定表明,其中一新种,被定名为中华团结蛤Abra simica sp.nov。,属樱蛤超科中的双带科(Semelidae)。模式标本保存于中国科学院海洋研究所。 相似文献
5.
6.
报道了中国碱蓬属植物一新种——垦利碱蓬Suaeda kenliensis J.W.Xing sp.nov.。该种与南方碱蓬Suaeda australis(R.Br.)Moq.相近,但系一年生,种子具圆盘状和卵形两种形状,直径约2~3mm,叶长可达5~7 cm,无不定根,与南方碱蓬相区别。垦利碱蓬生长于潮间带和海水周期性淹没处。耐高盐,区域内海水盐度为25,滩涂表层含盐量在退潮后经日晒蒸发可达60‰以上。常形成单一种群的红海滩植被景观。模式标本存:中国科学院海洋生物标本馆;编号:MBM286537。采集地:莱州湾垦利海域潮间带泥滩。采集人:邢军武、曲宁、钟芳。 相似文献
7.
Burmaneura minuta gen. et sp. nov., the first araripeneurine antlion in amber, is characterized, described and compared with the modern and Mesozoic Myrmeleontidae. The precise position of the fossil within this group is debatable. Interestingly, despite a rather rich fossil record, all Mesozoic Myrmeleontidae belong to subfamilies that are not recorded in the Cenozoic, although this might merely reflect the artificiality of the classification as the extinct groups may be paraphyletic with respect to their younger counterparts (e.g., Araripeneurinae may very well be nothing more than a stem group of no classificatory value). 相似文献
8.
Annulipsyllipsocus andreneli gen. et sp. nov. and A. inexspectatus gen. et sp. nov., the first records of the Psyllipsocidae from the Cretaceous amber of Myanmar are described, illustrated and their taxonomic position discussed. The new genus is characterized by antennae with 16 segments; flagellomeres with secondary annulations; radial cell closed, five-angled, bulged on its R1 border; triangular pterostigma. Species belonging to Annulipsyllipsocus gen. nov. are polymorphic. The described taxa represent the earliest evidence for polymorphism in Psocodea. A checklist of all known species of Psyllipsocidae is given. 相似文献
9.
Fossil leaves resembling Nothofagaceae have been investigated from the Eocene of western Antarctica and a new form genus Nothofagofolia is proposed for these kinds of fossils. Some new specimens belonging to this form genus are described. They were collected
from the Fossil Hill locality of Fildes Peninsula, King George Island, South Shetland Islands, western Antarctica. Two new
species, two new combinations and an unnamed species are reported. A number of published Nothofagus leaf fossils from the same locality are discussed and revised. As a result of these studies of Nothofagus leaf morphology, we conclude that (1) Nothofagus probably originated in high latitudes of the Southern Hemisphere during the middle-late Late Cretaceous and diversified,
dispersed gradually to the lower latitudes of the same hemisphere; (2) leaf morphological characters are significant for the
systematics of the family Nothofagaceae, especially at the intrageneric level; and (3) extant species of Nothofagus known from southern temperate areas have more primitive leaf morphological characters and lower leaf ranks than those from
tropical mountains as well as those of the Fagaceae and Betulaceae.
Supported by the Foundation of State Key Laboratory of Palaeobiology & Stratigraphy, Nanjing Institute of Geology and Palaoentology,
Chinese Academy of Sciences (Grant No. 013106), the National Natural Science Foundation of China (Grant No. 30670159) and
the Fund of Innovation Program by Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences 相似文献
10.
Wang Wenli Institute of Natural History Beijing Natural History Museum Yang Zunyi 《《地质学报》英文版》1993,67(3)
A new insect family Liaoximordellidae (fam. nov.) has been named for a well-preserved specimen which was collected from the Upper Jurassic outcropping west of Daxinfangzi Village, Lingyuan County, Liaoning Province. The specimen can not be put into Mordellidae or Praemordellidae because it possesses some original and intermediate characters in morphology. It serves the study of mordellid evolution. Besides, the fossil group associated with the insect is important for the stratigraphic division of the Mesozoic in western Liaoning. 相似文献