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51.
A rich and diverse assemblage of arthropods and non‐biomineralized macroalgae occurs in the Upper Devonian marine deposits of the Holy Cross Mountains, central Poland. The phrase Kowala Lagerstätte is herein proposed for the fossil‐bearing deposits confined to the lower Famennian marly shale and limestone succession of the famous Kowala Quarry. The arthropod fauna is represented by phosphatic exoskeletal remains that still preserve the fine micro‐ornamentation of the cuticle. The fauna includes crustaceans and crustacean‐like taxa such as thylacocephalans, phyllocarids and angustidontids (in order of abundance). The non‐biomineralized algae, represented by at least three morphotypes, occur as carbonaceous compressions of their thalli while still preserving fine details including bundles of thin tubular projections. Although their general appearance is reminiscent of some Early Palaeozoic non‐calcified Dasycladales algae, their true taxonomic position is still uncertain. Lithology, as well as faunal and phytoplankton content point to a pelagic sedimentary environment. Impoverished benthic fauna, sediment lamination and geochemical signatures indicate at least periodic bottom‐water dysoxic to anoxic conditions. Thus, the preservation of arthropod cuticle and non‐calcified algae was primarily governed by oxygen‐deficient bottom waters that prevented bioturbation and scavenging during their burial.  相似文献   
52.
Cuvillierinella salentina Papetti and Tedeschi, 1965 and its related species of the Rhapydioninidae family are widely distributed in the Western Mediterranean region by Campanian–Maastrichtian time. C. salentina, the type species of the genus, is studied in rich populations from its Italian type locality, and several other spots from Greece and Spain. It shows great variability: the well-known type coexists with streptospiral tests almost devoid of endoskeleton and wholly planispiral tests with fine mesh-like endoskeleton, as well as many intermediates. Such populations reflect the large capacity of evolution of at least the group of miliolids from which these populations are derived, if not the species itself. The genera Murciella and Cyclopseudedomia are probably the most direct offshoots, but other taxa appear to arise from this species or at least from the same stock of origin. In the same genus and at the same time (middle part of Campanian age, “CsB6a” zone), two new species are described, both hesitating between the streptospiral and planispiral coiling: – C. fluctuans nov. sp., from Greece, A tests being either streptospiral or planispiral, with primary and secondary chamberlets taking the aspect of polygonal isodiametric network and – C. perisalentina nov. sp., from Italy, with persistent streptospiral coiling and disordered arrangement of secondary chamberlets which allow us to consider its relation with species of the genus Pseudochubbina, hitherto of completely enigmatic origin. Assigned to the same genus, from Upper Campanian–Lower Maastrichtian time (“CsB6b” zone), C. aff. pylosensis, probably related to C. pylosensis, is studied from several populations, and constitutes, with the above mentioned species, what is called C. gr. salentina. Based on material from the CsB6b zone, the new genus Metacuvillierinella nov. gen. is introduced; M. decastroi nov. sp., type species of the new genus, known from Greece and Italy, shows characters common to C. gr. salentina, such as milioline to streptospiral nepionic coiling, large endoskeleton mesh, associated with some original characters, such as the unusual conjunction of the advolute coiling and absence of any final unrolling together with very low dimorphism of generation; this results in flat tests, often sigmoid shaped in axial section, very rare in the family. Thus, the genus Cuvillierinella, and especially C. salentina, appears as a possible source, or at least not far from the origin, of a number of taxa related to one another, constituting a large part of the Rhapydioninidae family. They are gathered together inside the new subfamily Cuvillierinellinae, distinct from the subfamily Rhapydionininae sensu stricto (comprising Rhapydionina and Fanrhapydionina) which makes a different and parallel branch, from Upper Campanian (CsB6b zone) to the end of Cretaceous time (CsB7 zone).  相似文献   
53.
About one hundred papers and studies have been utilized for a synthesis of ostracode palaeobiogeography during the Frasnian and Famennian. The pelagic entomozoid species have worldwide distributions: they are not used for distinguishing the palaeobiogeographic areas. Five provinces probably existed during the Frasnian and five during the Famennian. The palaeobiogeographic area of the Palaeotethys is constant during this time. There are important faunistic relations between the Western Canadian Platform and the Russian Platform, that is to say, along the Northern margin of the North-Atlantic Continent, during Late Devonian time. The province of Southeastern Asia remains isolated. The number and limits of the palaeobiogeographic areas have been controlled by climate and some geographical barriers.  相似文献   
54.
《Geobios》2016,49(3):191-200
Non-calcified algal remains were collected from the lower Famennian deposits at the Kowala quarry in the Holy Cross Mountains, central Poland. Each specimen is represented solely by vegetative organs. On the basis of the material collected, a new algal genus and species has been formally erected. Vittella dixii nov. gen., nov. sp. (Order ?Bryopsidales) includes thalli consisting of long bundles of hair-like filament structures arranged in parallel fashion to the thallus length. Some other algal remains are regarded as Inocaulis-like forms. They possess long, flat blades with entire margins, and are ornamented with very dense, hair-like projections. The rest of the specimens found so far has been illustrated and tentatively classified as probably belonging to either Bryopsidales or Dasycladales algae. The exceptional preservation of the non-calcified algal thalli investigated suggests that special taphonomic conditions have prevailed during sedimentation of the lower part of the Famennian Kowala section. These may have involved rather rapid burial in oxygen-restricted (dysoxic and anoxic) sea-bottom environment, inhibiting the activities of scavengers and bioturbators, as well as oxidative degradation. The preservation of the algae, together with sedimentological and geochemical characteristics of the host rocks indicate that they rather represent parautochthonous assemblage, buried close to their natural habitat.  相似文献   
55.
《Palaeoworld》2022,31(2):258-276
Late Devonian–Early Carboniferous spores recovered from the depths of 2140 m to 2031.3 m in the CSDP-2 Borehole in the southern Yellow Sea are systematically documented to characterize palynological associations for the stratigraphic correlation. The taxonomic study identifies 96 species belonging to 48 genera, including a re-examination of 33 previously described and indeterminate species. Three palynological associations are established for the Wutong Formation in the CSDP-2 Borehole. In ascending order, these are the late Famennian Aneurospora asthenolabrataGeminospora lemurata (AL) Association from the proposed Guanshan Member, the latest Famennian Cymbosporites circinatusAsperispora acuta (CA) Association from the lower part of the proposed Leigutai Member, and the Tournaisian Auroraspora macraLophozonotriletes involutus (MI) Association of the upper part of the latter member. The AL and CA associations are correlated with the palynological assemblages in the Guanshan Member, and those in the lower to middle parts of the Leigutai Member of the Wutong Formation that outcrops in the suburbs of Nanjing and southern Jiangsu. The MI Association is similar to those derived from the uppermost beds of the subsurface Wutong Formation and is dated as early Tournaisian.  相似文献   
56.
Stromatoporoidea recorded for the first time from the Lower Famennian of the Kuznetsk Basin are described. The assemblage studied includes three new species, Actinostroma quasifenestratum sp. nov., Kyklopora tomiensis sp. nov., and Coenostroma rarum sp. nov., and three previously known species of different genera.  相似文献   
57.
58.
The Canning Basin of northwestern Australia is a key area for understanding global changes at the “Kellwasser Events” and the Frasnian‐Famennian boundary. Frasnian stromatoporoid‐coral‐cyanobacterial reef platforms stretched out for enormous distances along the palaeoshelf but in the early Famennian they were completely replaced by cyanobacterial reef platforms. An iridium anomaly in the sequence was formerly believed to be at or close to the boundary and was interpreted as possible evidence for an asteroid impact. Recent field work and detailed biostratigraphy in the area east and southeast of Fitzroy Crossing has given dating relevant to the timing and extent of sea level changes, hypoxic incursions and reef backstepping. Goniatites and conodonts provide correlations with the international biostratigraphy.

In the Horse Spring area the stage boundary falls within the Virgin Hills Formation which normally has a rich pelagic goniatite, nautiloid and conodont fauna. In the latest Frasnian (Zone 13 of Klapper 1989; regional Sphaeromanticoceras lindneri Zone) large allochthonous reef blocks moved downslope into the open marine basin. A diverse gastropod fauna is associated with the last atrypid brachiopods. The faunal record at the immediate boundary is obscured by dolomitisation but manticoceratid goniatites range into this level. There is no evidence for the organic‐rich dark Kellwasser limestone facies.

In the McWhae Ridge area two Frasnian goniatite horizons with Beloceras trilobites and the giant Mamicoceras guppyi and Sphaeromanticoceras lindneri transgress over the reef slope. Stromatolitic cyanobacterial beds mark condensations. Again there is no trace of the oxygen‐depleted Kellwasser facies. However, as at Horse Spring, manticoceratids persisted into dolomitic marker beds that have no other preserved macrofauna. The iridium anomaly associated with Frutexites postdates the Frasnian‐Famennian boundary and was formed by cyanobacterial concentration.  相似文献   
59.
This study defines a new bivalve species, Naiadites devonicus nov. sp., of Famennian (Late Devonian) age. The material was excavated from the non-marine deposits of the Waterloo Farm Lagerstätte in South Africa, which form part of the Witpoort Formation (Witteberg Group, Cape Supergroup) of the Cape Fold Belt region. The type material of Naiadites devonicus nov. sp. is preserved in metamorphosed, clayey to silty mudstones of a coastal estuarine to lagoonal facies, deposited along the shoreline of the Agulhas Sea, in a high-palaeolatitude Gondwanan setting. The new bivalve species is the stratigraphically oldest representative of the genus Naiadites Dawson. It is a faunal element of a high-latitude palaeoecosystem, immediately preceding the Hangenberg extinction event at the end of the Late Devonian.  相似文献   
60.
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