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1.
Multiplicatispirifer, a new delthyridoid brachiopod genus with a gently divergent capillate micro-ornamentation and bifurcating costae on flanks, sulcus and fold, has been identified in the Mdâouer-el-Kbîr Formation of the Dra Valley (southern Anti-Atlas, Morocco). Its type speciesMultiplicatispirifer foumzguidensis n. gen., n. sp., at present the only species of this genus, is described. This form has hitherto been determined asFimbrispirifer orStruveina by various authors. In this work, the new genus is compared with the multiplicate and capillate spiriferid genera with bifurcating costae which also have costae in the sulcus and on the fold:Costispirifer andPerryspirifer from North America,Elymospirifer from South China,Borealispirifer from Asia andMultispirifer from Central Europe. The relation ofMultiplicatispirifer to the fimbriateFimbrispirifer, Struveina andVandercammenina, from which it is distinguished by its capillate micro-ornamentation, is discussed. The new genus is hitherto only known from the Moroccan southern Anti-Atlas. Its colsest relatives, taxa ofCostispirifer, occur in the Eastern American Realm (Gaspé, Canada and the eastern United States) and the Nevada Province (western United States).Multiplicatispirifer occurrences are restricted to the Lower/Upper Emsian boundary interval (upper Lower Devonian). The reasons for a possible migration corridor between North America and North Africa before Emsian time are discussed.  相似文献   

2.
Two new species ofPseudopetigurus are described from northern Hunan Province, China.P. deprati n. sp. is abundant in the upper Zitai Formation (upper Arenig) of Shuanghong, Baiyun, Shimen County, andP. expansus n. sp. occurs throughout the Jiuxi Formation (Arenig — lower Llanvirn) of Panjiazui, Taoyuan County. These formations represent outer shelf facies from the Jiangnan Transitional Belt of the South China Plate, close to the southeast margin of the Yangtze Platform. BothP. deprati andP. expansus show similarities to Upper Ordovician species ofPseudopetigurus recorded from South China. Other species ofPseudopetigurus are known almost entirely from cranidia, but pygidia and librigenae are also described for both new species, and the first known hypostome assigned to the genus is described forP. expansus. These two species are ecologically important members of offshore trilobite faunas during the Arenig — Llanvirn and define the outer shelfPseudopetigurus Association of South China. Despite being a deep-water genus,Pseudopetigurus is biogeographically restricted to the western margin of the Gondwanan craton and neighbouring regions of Baltica.   相似文献   

3.
The earliest Permian faunal successions of central Patagonia show compositional changes that probably reflected the environmental warming at the end of the Gondwana glaciations. Bivalves of Asselian to probably Early Tastubian age are described. A new genus,Sueroa, is proposed to reunite a previously known species and a new species,Sueroa andreisi n. sp. Another five new species:Parallelodon? quichaurensis n. sp.,Heteropecten cortignasi n. sp.,Etheripecten saraviae n. sp.,Streblopteria montgomeryi n. sp. andPraeundulomya moreli n. sp. are described. Two previously known species:Malimania patagoniensis (González) andEuchondria sabattiniae González are revised and new occurrences are reported. A further eleven species are described, but they are left in open nomenclature being because they are insufficiently known; these are:Phestia? n. sp.,Modiolus sp.,Palaeoneilo sp.,Stutchburia sp.,Schizodus sp.,Vacunella? sp.,Edmondia sp.,Myonia? n. sp.,Myonia? sp. andPachymyonia? n. sp.  相似文献   

4.
Phyllocarids other thanNahecaris stuertzi are rare in the Hunsrück Slate. The few specimens, mostly fragmentary, are here described and referred to seven different taxa:Heroldina rhenana, Ceratiocarina fam. et gen. indet.,Montecaris? sp.,Nahecaris? halssi, Nahecaris sp.,Dithyrocaris? sp., and Rhinocarididae gen. et sp. indet. Almost none of them yields diagnostic characters permitting identification at even generic level. Some may be different body regions of the same taxon. The Hunsrück Slate phyllocarids, includingNahecaris, preserve characters which indicate an affinity with the leptostracan Malacostraca. Schram’s (1986) reassignment of the phyllocarids to the Class Phyllopoda is therefore rejected.  相似文献   

5.
《Palaeoworld》2023,32(2):235-251
Middle to Late Ordovician brachiopods from the Huadan Formation (upper Darriwilian–Sandbian) of Ningnan County, southern Sichuan Province, are systematically documented here for the first time. The locality belongs to the western margin of the Upper Yangtze Platform, South China palaeoplate, and the brachiopod fauna includes one new genus and three new species as well as five other constituents: Hingganoleptaena sp., Acculina zhongliangziensis n. sp., Ningnanmena longisepta n. gen. n. sp., Kassinella (Trimurellina) minuta n. sp., Lepidorthis typicalis Wang, 1955, Protoskenidioides weixinensis Zhan and Jin, 2005, Porambonites transversus Xu, Rong and Liu, 1974, and Psilocamerella sp. Taxonomically it is a typical representative of a Middle to early Late Ordovician brachiopod fauna, and, together with some other evidence from other fossil groups like trilobites, conodonts, chitinozoans, a late Darriwilian–Sandbian age could be inferred for the horizon yielding this fauna. According to the richness of each constituent, this fauna is suggested to be called the Acculina-Ningnanmena fauna (ANF). Numerical palaeogeographical analysis shows that two broad palaeobiogeographic provinces could be recognized during this particular time interval, and, although the ANF is grouped into the South China cluster, it shares very little similarity with other representatives of that group except for two cosmopolitans. It further confirms that the Great Ordovician Biodiversification Event (GOBE), in other words the Ordovician radiation, was actually manifested by the strong localization of major marine organisms such as brachiopods, trilobites, graptolites, etc.  相似文献   

6.
A new genus and three new species of Figitinae (Hymenoptera: Figitidae) are described from Colombia: Ferpereira Pujade-Villar n. gen., Ferpereira fiorellae Pujade-Villar n. sp., Neralsia levis Pujade-Villar & Petersen-Silva n. sp., and Figites colombiensis Pujade-Villar & Paretas-Martínez n. sp., which is the first species of Figites Latreille from Colombia and the second from South America. The diagnostic characters of these new taxa are illustrated.  相似文献   

7.
The first calcitic thecas of edrioasteroids from the Rheinisches Schiefergebirge are described:Timeischytes leunisseni n. sp.,Timeischytes prescheri n. sp. andRhenopyrgus sp. are from the Middle Devonian of the Eifel Hills. The morphological features ofTimeischytes lead to the assumption that in this genus paedomorphosis has been a long-lasting process.  相似文献   

8.
9.
A new middle Ordovician fauna including conodonts and brachiopods is described from the early Llanvirn Zhyrykaus Formation, Malyi Karatau Range, southern Kazakhstan. The fauna includes the lingulate brachiopodsHyperobolus fragilis n. sp. andTalasotreta apollonovi n. gen. n. sp., as well as the conodontsCordylodus? cf.horridus, Drepanoistodus? sp.,Erraticodon sp.,Parapaltodus simplicissimus, Prioniodus (Baltoniodus) sp.,Protopanderodus cf.varicostatus, andWalliserodus sp. s. f. It represents the first record of Llanvirn conodonts and Ungulate brachiopods from southern Kazakhstan.  相似文献   

10.
Four outcrops (three of which were new) in the Northern Rhenish Schiefergebirge delivered several ophiuroids from the high Famennien. Following forms are described:Protaster?ubaghsi n. sp. and a juvenile protasteroid, gen. et spec, indet., 2 new species ofFurcaster to be treated taxonomically only after revision of this genus, many specimens ofOphiaulax decheni showing plates of the primary rosette and other hitherto undescribed structures,Stephanoura belgica with many juvenile specimens, andOnychaster?velbertensis n. sp. as the first representative of the Onychasteridae in the Rhenish Schiefergebirge.  相似文献   

11.
An early Lochkovian trilobite faunule from the Catavi Formation, Cochabamba Department, Bolivia, includesPaciphacops waisfeldae n. sp. andKazachstania gerardoi n. sp. The latter species also occurs in the upper part of the Los Espejos Formation in the Precordillera of San Juan, Argentina, and the former is sister species toP. argentinus (Thomas 1905) from the Los Espejos Formation. South AmericanPaciphacops species are allied to North American, rather than Australian, congenerics.Kazachstania Maksimova 1972 appears to include some species previously assigned toReussiana ?najdr 1987. Records ofPaciphacops andKazachstania provide evidence that earliest Devonian trilobites of Andean South America are largely geographically widespread taxa.  相似文献   

12.
The Lower Ordovician conodont species first described asScolopodusl peselephantis Lindström 1955, has a seximembrate apparatus of laterally compressed, variously curved and flexed coniform elements. These are very small and invariably striated or multicostate. The taxon is reassigned toDecoriconus Cooper 1975, a genus hitherto known by species from Upper Ordovician and Silurian strata. These younger species share several characteristic morphological features with the older species investigated in this work. When studied in detail, it was discovered thatD. peselephantis was the first species in a lineage which also included two successive new species. Of these,D. mercurius n. sp. occurs in the middle Arenig, whileD. pesequus n. sp. ranges from the late middle Arenig and at least through the Llanvirn, possibly even into the Caradoc. These new species, which were previously included intoS.? peselephantis, are described and their geographic distribution investigated. In addition, a probable homeomorphic form ofD. peselephantis, Toxotodus? gabriellae n. sp., is diagnosed.  相似文献   

13.
14.
A mass occurrence of schooling, weakly sclerotized eocaridid shrimps in the Early Devonian pelagic environment of northern Russia suggests that the body-plan of the Eumalacostraca originated as an adaptation to swimming in the open sea. They probably replaced their ecological analogues, the archaeostracan phyllocarids Caryocaris , as a consequence of the rebuilding of the global marine environment during the later Ordovician. This may explain the rarity of the eumalacostracans in the Devonian and the difficulty with documenting their links with the archaeostracans. The new eocaridid shows similarities to the Carboniferous Anthracophausia in the general appearance and weak sclerotization of the carapace and appendages, but lacks its derived characters. The morphology of the pleural lobes, which have minute spines, is the only identified distinguishing character of the proposed new genus and species Archangeliphausia spinosa gen. et sp. nov. Its carapace was probably firmly connected dorsally with the thoracic segments. The only associated fossils of the assemblage represent a bizarre archaeostracan Pechoracaris aculicauda gen. et sp. nov., with a weakly sclerotized carapace lacking any hinge or rostral plates but with reduced furca, an extremely long caudal spine and pleopods transformed into spines.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 142 , 83–90.  相似文献   

15.
Frasnian tentaculites from western part of Central-Afghanistan are described. Six of the 11 studied species are new:Dicricoconus dupliannulatus n. sp.,Dicricoconus ghukensis n. sp.,Dicricoconus gracilis n. sp.,Dicricoconus harundata n. sp.,Volynites kaminjensis n. sp. andAlternatus spatiosus n. sp. The fauna is appearing in two stratigraphic levels. The occurrence ofTentaculites donensis respectively ofDicricoconus tichomirovi, Dicricoconus tragula andUniconus livnensis confirmes the middle-upperfrasnian respectively the upperfrasnian age of both levels. The Devonian basin of Ghuk area was connected with the epicontinental sea of the Russian Plateform throughout the Frasnian and with the Libyan basin at least during upperfrasnian time.  相似文献   

16.
Three new species of the Oriental caliscelid planthopper genus Symplanella Fennah, S. hainanensis sp. n., S. recurvata sp. n. and S. zhongtua sp. n., are described and illustrated from South China. A checklist and a key to species of genus Symplanella are provided.  相似文献   

17.
Summary Neopolystoma kreffti n.sp. from the mouth and pharyngeal cavity ofEmydura krefftii (Pleurodira, Chelidae) in southern Queensland,N. macleayi n.sp. from the cloacal bursa, andN. australis n.sp. from the mouth and pharyngeal cavity ofEmydura sp. in New South Wales are described. The new species differ from other species of the genus mainly in the number and shape of the genital hooks. New locality records ofN. chelodinae fromChelodina longicollis and ofPolystomoides australiensis fromE. krefftii are given. ac]19821026  相似文献   

18.
Five new foliicolous species ofDimerella Trevisan (Gyalectaceae) are reported from a collection of lichens from Tanzania:D. flavicans sp. n.,D. pocsii sp. n.,D. subdilucida sp. n. ad int.,D. tanzanica, sp. n. andD. usambarensis sp. n. A determination key is provided to all the known African foliicolous species.  相似文献   

19.
From the Early Aptian (“Tæck”) of Heligoland (North Germany) three new species, one new genus and one new family of Teuthids are described:Mastigopbora stuehmeri n. sp.,Boreopeltis helgo landiae n. gen. n. sp. andMaioteuthis damesi n. sp. The new genusBoreopeltis n. gen. ist placed in the family Plesioteuthididae NAEF 1921. The genusMastigopbora OWEN 1856 previously attributed to the family Loligosepiidae van Regteren Altena 1949 is proposed as type genus of the new family Mastigophoridae. Two poorly preserved specimens cannot be identified specifically (?Trachyteuthis sp. andPlesioteuthis sp.).  相似文献   

20.
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