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1.
Middle Permian Pseudoalbaillella from the Xiaodong area in South China were studied using fossil morphology. Short forms of Pseudoalbaillella fusiformis (Holdsworth and Jones), Pseudoalbaillella internata Wang, and Pseudoalbaillella monacantha (Ishiga and Imoto), characterized by a short and skirt-like pseudoabdomen, were confirmed. We conclude that the short forms were derived from their respective species by breaking off during disruptive processes. If this is true, there may be structurally weakened parts in the pseudoabdomen.  相似文献   
2.
Nikolaos Salakius 《Geobios》1982,15(6):873-889
A new, strongly spiroconvex Globotruncana species,Globotruncana pseudoconica nov. sp., is described from the Maastrichtian of Tunisia. It is distinguished from Globotruncana conicaWhite in morphology and phylogeny. Some Maastrichtian, strongly spiroconvex specimens referred to as Globotruncana conicaWhite, are shown to be identical to Globotruncana pseudoconica nov. sp. The new species reveals close affinity with Globotruncana falsostuartiSigal from which it has evolved during the middle Lower Maastrichtian.  相似文献   
3.
The Campanian–lower Eocene sedimentary succession in the Kharga Oasis yields rare cephalopods that have so far received little attention. Eight cephalopod species; six nautiloids and two ammonites, are identified in the study area. The nautiloids are referred to five genera in three families. All nautiloid species are recorded from the Paleocene and Eocene rocks, two of which are described as new, as follows: Cimomia kurkurensis nov. sp. and Deltoidonautilus hassani nov. sp. The two ammonite species are Libycoceras ismaelis (von Zittel, 1884) and Baculites ovatus Say, 1820, representing the families Sphenodiscidae and Baculitidae, respectively. Baculites anceps of Quaas (1902, non Lamarck, 1822) from the Maastrichtian of the Western Desert of Egypt is here assigned to Baculites ovatus. The palaeobiogeography of these species is studied in detail.  相似文献   
4.
Kurzfassung  Anhand von Material aus den mitteldevonischen Kalkmulden der Eifel (Rheinisches Schiefergebirge) wird eine auf Kelch- und Armsegmenten der Cupressocrinitidae C.F.Roemer, 1854 aufliegende und deutlich getrennte Skelettschicht als Exoplacoidschicht beschrieben. Aufbau, Morphologie, Ultrastruktur und geochemisches Signal werden vorgestellt, die Funktionsmorphologie diskutiert. Die Ausbildung der Exoplacoidschicht führt innerhalb der bisher monotypischen Familie Cupressocrinitidae C.F.Roemer, 1854 zur Abtrennung der neuen GattungenRobustocriniles n. gen. undAbbreviatocrinites n. gen. Die GattungRobustocrinhes n. gen. undCupressocrinites Goldfuss, 1831 besitzen eine monolamellare Exoplacoidschicht und unterscheiden sich durch weitere anatomische Merkmale von der durch eine multilamellare Exoplacoidschicht charakterisierten GattungAbbreviatocrinites n. gen. Dieser Gattung wird neben anderen, bisherCupressocrinites untergeordneten ArtenAbbreviatocrinites geminatus n. gen. n. sp. mit besonders deutlicher multilamellarer Exoplacoidschicht zugeordnet.   相似文献   
5.
《Comptes Rendus Palevol》2018,17(6):351-356
Fossils belonging to Ripidiinae are rare. Here, we describe and figure a remarkable new genus and species of Ripidiinae, Protoripidius burmiticus gen. et sp. nov., from the Upper Cretaceous amber of Myanmar. Protoripidius can be placed in the extant subfamily Ripidiinae based on the widely separated and abbreviated elytra (in male), unfolded hind wings, simple claws and the absence of tibial spurs. Protoripidius bears many transitional features shedding new light on the relationships of the two extant tribes of Ripidiinae. The discovery also highlights the palaeodiversity of the subfamily Ripidiinae in the mid-Cretaceous.  相似文献   
6.
Citizen science Citizen science is performed on a honorary basis. Citizen scientists (”Citizen Science proper“) have no professional employment in the relevant field of research and differ very much in their educational background, specific knowledge and amount of time dedicated to the subject of research. Today, citizen science has become especially important in some fields neglected by professional science, e.g. regional research. Recently, another form of citizen science has gained much attention, in which usually many citizen scientist are active (”Citizen Science light“). Internet, smartphone and georeferencing by GPS are important tools for collecting, documenting and communicating the observation data. Besides the scientific results, social relevance through participation and information of citizens (e.g. for conservation issues) play a very important role in these projects. The recently strongly increasing interest in and contribution to citizen science plays an important role to strengthen the link and communication between science and society.  相似文献   
7.
A remarkably specialized parasitoid wasp of the family Scelionidae (Platygastroidea) is described and figured from mid-Cretaceous (Cenomanian) amber of the Hukawng Valley in northern Myanmar. Geoscelio mckellari Engel and Huang, gen. et sp. nov., is unique for its combination of a compact body, 12 antennal flagellomeres, a 1-2-2 tibial spur formula, a distinct malar sulcus, deeply impressed notauli, complete reduction of the wings, and basal crenulae on the metasomal terga and sterna, among many other features, and is placed within a separate tribe, Geoscelionini Engel and Huang, trib. nov. This is the first flightless species of Platygastroidea known from the Mesozoic, and its affinities with other Mesozoic and extant lineages are discussed.  相似文献   
8.
The discovery in the uppermost Jurassic of Lebanon of a species of the ostracod genus Microceratina Swanson, 1980 (Eucytherurinae), of which the oldest known species was until now of Maastrichtian age, confirms the Tethyan origin of this genus. Two new species are created: Microceratina bhannesensis nov. sp. from the Upper Jurassic (Kimmeridgian) of Lebanon, and Microceratina azazoulensis nov. sp. from the Cenomanian of Morocco. The genera Chapmanicytherura Weaver, 1982 and Erratacytheridea Herrig et al., 1997, are considered as probable junior synonyms of Microceratina. An exhaustive bibliographical analysis allowed to identifying several other Cretaceous species susceptible to be assigned to the genus Microceratina.  相似文献   
9.
Relationships of the newly discovered dwarf crocodiles from Mauritania were inferred from mitochondrial 12S sequences. Specimens from 13 different Crocodylus niloticus populations (from East Africa, West Africa and Madagascar) were compared. Additional representatives of the genus Crocodylus (one from Africa and one from Australia), the African genus Osteolaemus and the South American alligatorid Paleosuchus palpebrosus (as outgroup) were included in the analysis. Maximum-likelihood and Bayesian analyses yielded relationships that were strikingly different from currently prevailing phylogenetic hypotheses. Both analyses consistently revealed two groups, one consisting of the monophyletic West- and Central African populations and the other of a paraphyletic group containing the East African and Madagascan populations. High genetic divergence between those groups indicates separation on the species level. Furthermore ‘Ccataphractus is clearly shown not to be a member of the genus Crocodylus. The resulting nomenclatural changes are discussed. To cite this article: A. Schmitz et al., C. R. Palevol 2 (2003).  相似文献   
10.
Jeannine Geyssant 《Geobios》1985,18(5):677-680
The type-species of the genus SimocerasZittel isS. biruncinatum (Qu.). This genus includes the species-group biruncinatum (Qu.) — admirandum (Zitt.). The new genus Volanoceras is created for the volanense (Opp.) species-group which is excluded from the genus Simoceras.  相似文献   
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