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The relatively rich assemblages of shark teeth from pelagic limestone (Mississippian, late Viséan, late Asbian-middle Brigantian) of three northern European regions: the Rhenish Mountains (Westenfeld Quarry, Germany), the Holy Cross Mountains (Todowa Grząba at the edge of Ostrówka Quarry, Poland), and Derbyshire (Cawdor Quarry, Matlock, England, UK) display certain similarities, with the absolute predominance of the teeth of Falcatidae (small Symmoriiformes) and the constant presence of Thrinacodus spp. The largest and most diverse assemblage from Todowa Grząba contains at least three species of a falcatid Denaea, a xenacanthimorph Bransonella nebraskensis, a newly described phoebodontid Thrinacodus dziki sp. nov., a few ctenacanthiform and euselachian teeth, and two abraded euchondrocephalan dental elements. Anachronistidae, common in the most of late Viséan pelagic faunas, are absent from Todowa Grząba and Westenfeld. The material under study differs from the shallow-water chondrichthyan fauna, hitherto described from the Mississippian carbonate platform facies, by its taxonomic content (particularly almost total absence of Euchondro-cephali), generally lower diversity, and higher frequency of small teeth.
Fourty two species referred to 21 genera and 2 subgenera are described; one genus and 5 species are new: Diphyphyllum rarevesiculosum sp.n., Lithostrotion (Siphonodendron) dobrolyubovae sp.n., L. (S.) rossicum strzelcense subsp.n., L. (S.) rossicum parvum subsp.n., Lublinophyllum fedorowskii gen. et sp.n. Genera Orionastraea and Turbinatocaninia are for the first time recorded in Poland. Heterophyllidae with 5 septa and pentagonal cross-section are recorded. Blastogeny has been studied in 13 species and subspecies. Axial increase has been studied in detail in Lithostrotion (Siphonodendron) dobrolyubovae sp.n. Taxonomic division of Rugosa based on blastogeny, is demonstrated to be questionable in some cases. Fusion of corallites has been observed in colonies of Lithostrotion and Lonsdaleia colonies. Existence of holotheca in Orionastraea aff. magna Kato & Mitchell has been proved.
Two new species of sphenophyllalean strobili with in situ spores are proposed from the Radnice Basin of the western and central Bohemian Carboniferous continental basins of the Czech Republic. Bowmanites brasensis sp. nov. from Břasy (Matylda Mine) and B. pseudoaquensis sp. nov. from Ovčín locality are determined mainly on the basis of their spores, which are about 100 μm in diameter. The thick−walled exine of the miospores is laevigate or sometimes very finely scabrate on the proximal contact area. Spores resemble the dispersed species Punctatisporites obesus. Cones of B. brasensis and B. pseudoaquensis are organically connected with stems having prominent blade leaves and represent a new group of sphenophyllalean strobili.
The fusulinid foraminifers of Schellwienia arctica (Schellwien, 1908) have been investigated from Polakkfjellet Mt., south Spitsbergen, and used as biostratigraphic marker for the latest Carboniferous-?earliest Permian strata of the Treskelodden Formation. A series of thin sections enable to investigate the internal structure and growth pattern of individual specimens. The observed variation of growth suggests dynamic environmental conditions at the investigated location and most likely over one-year long life span of this foraminifer.
Sphenacodontid synapsids were major components of early Permian ecosystems. Despite their abundance in the North American part of Pangaea, they are much rarer in Europe. Among the few described European taxa is Neosaurus cynodus, from the La Serre Horst, Eastern France. This species is represented by a single specimen, and its validity has been questioned. A detailed revision of its anatomy shows that sphenacodontids were also present in the Lodève Basin, Southern France. The presence of several synapomorphies of sphenacodontids—including the teardrop-shaped teeth—supports the assignment of the French material to the Sphenacodontidae, but it is too fragmentary for more precise identification. The discovery of sphenacodontids in the Viala Formation of the Lodève Basin provides additional information about their ecological preferences and environment, supporting the supposed semi-arid climate and floodplain setting of this formation. The Viala vertebrate assemblage includes aquatic branchiosaurs and xenacanthids, amphibious eryopoids, and terrestrial diadectids and sphenacodontids. This composition is very close to that of the contemporaneous assemblages of Texas and Oklahoma, once thought to be typical of North American lowland deposits, and thus supports the biogeographic affinities of North American and European continental early Permian ecosystems.
The position of the Palaeozoic Anthracoptilidae has been a major problem of insect systematics for over a century. The previous hypotheses suggested affinities of Anthracoptilidae with the Palaeodictyopteroida, Protorthoptera, Hypoperlida, stem-Mantodea, Paraneoptera, Holometabola, or Eoblattida. Herein we put forward a new hypothesis based mainly on a comprehensive re-evaluation of the wing venation characters and re-examination of the type material of Anthracoptilus perrieri and Mesoptilus dolloi. The Anthracoptilidae are considered as belonging to the paoliid lineage, sister group of the Dictyoptera. In particular this result refutes the presence of Mantodea in the Paleozoic fossil record. The two families Strephocladidae and Strephoneuridae, are considered as junior synonyms of the Anthracoptilidae, while the previous synonymy of the Anthracoptilidae with the Ischnoneuridae is rejected. We consider the Permarrhaphidae, previously considered as synonym of the Anthracoptilidae, (and Permarrhaphus) as Insecta incertae sedis. The following new taxa are proposed: Mesoptilus carpenteri sp. nov. from the early Permian of Wellington Formation in Oklahoma (USA) which extends the range and distribution of the genus; Pseudomesoptilus gen. nov. is designated to include Mesoptilus sellardsi; Strephocladus permianus sp. nov. from the middle Permian of South of France; Westphaloptilus gallicus gen. et sp. nov. from the Bashkirian of the North of France.
The cameral and intrasiphonal deposits of a Pennsylvanian straight nautiloid (Pseudorthoceratidae) are studied in order to understand the formation of these deposits. The specimens from the Buckhorn Asphalt deposit (Oklahoma) are exceptionally preserved including original aragonite and microstructures. The specimen investigated survived a predation attempt and shows bite marks on the phragmocone. This is the second report of an ectocochleate cephalopod and first report of an orthoconic nautiloid which survived massive damage of conch and siphuncle. For the first time, a high−magnesium calcitic mineralogy of cameral deposits is documented. These deposits were formed in alternation with aragonite in a chamber which was perforated during the unsuccessful predation attempt. The animal formed the chamber deposits throughout its entire lifetime and the siphuncle played a major role in formation of the cameral deposits.
An early Late Tournaisian (Early Carboniferous/Mississippian) ammonoid fauna is described from the Tafilalt of south−eastern Morocco. Twelve genera, four of which are new, and eleven new species are represented: Becanites africanus sp. nov., Triimitoceras epiwocklumeriforme gen. et sp. nov., Irinoceras minutum sp. nov., Muensteroceras quadriconstrictum sp. nov., Eurites bouhamedensis sp. nov., Ouaoufilalites ouaoufilalensis gen. et sp. nov., Helicocyclus fuscus sp. nov., Pericyclus mercatorius sp. nov., Orthocyclus(?) sp., Bouhamedites enigmaticus gen. et sp. nov., Winchelloceras antiatlanteum sp. nov., and Progoniatites maghribensis gen. et sp. nov. Palaeogeographic analysis of Late Tournaisian ammonoid assemblages shows strong endemism at the species−level, but genera and families had a nearly global distribution in the equatorial seas. The new fauna contains the stratigraphically oldest known representatives of the important Carboniferous goniatite families Girtyoceratidae and Goniatitidae.
The verneuiliid brachiopod Changshunella yangi gen. et sp. nov. is described from the Early Carboniferous Muhua Formation of Guizhou, China. This rather unusual form is characterized by having very small shell dimensions (2.6–4 mm in length), a very high flat procline ventral interarea, and by having three prominent plications on both valves that are arranged in opposed folding; the last feature is characteristic for the family Verneuiliidae. We suggest that the family has been derived from an offshoot of the stock that produced the superfamilies Spiriferoidea, Paeckelmanelloidea, and Brachythyridoidea by developing opposed folding and loss of dental plates or dental adminicula as exemplified by Verneuilia and Changshunella gen. nov.
The Late Carboniferous amphibian genus Limnerpeton Fritsch, 1881 is revised on the basis of the type specimens of the eight original species described by Fritsch using material from Nýřany, Třemošná and Kounov, now in the Czech Republic. The type species Limnerpeton modestum is a nomen dubium restricted to a mandible that almost certainly belongs to an amphibamid temnospondyl but is not critically diagnostic. “Limnerpeton” laticeps and “Limnerpeton” macrolepis lectotypes are both small individuals of the same taxon as the later described Mordex calliprepes Steen, 1938 and thus form part of the hypodigm of Mordex laticeps comb. nov. “Limnerpeton” elegans is now Limnogyrinus elegans and is a member of the temnospondyl family Micromelerpetontidae. “Limnerpeton” obtusatum is a specimen of the microsaur Microbrachis pelikani. “Limnerpeton” dubium is an indeterminate tetrapod, probably either a temnospondyl or a pelycosaur. “Limnerpeton” difficile is a nomen dubium but the type is probably a small specimen of the tuditanomorph microsaur Crinodon limnophyes. “Limnerpeton” caducum is almost certainly a specimen of the ophiderpetontid aïstopod Oestocephalus granulosus. Several other described small temnospondyls from Nýřany are discussed and shown to be specimens of either Limnogyrinus elegans, Mordex laticeps or Amphibamidae incertae sedis. The tetrapod fauna at Nýřany includes four dissorophoid temnospondyls as proposed by Milner (1986) but with two changes in nomenclature. They comprise the branchiosaurid Branchiosaurus salamandroides, the micromelerpetontid Limnogyrinus elegans, the amphibamid Platyrhinops cf. lyelli and the primitive trematopid Mordex laticeps. These represent four of the five major dissorophoid families and demonstrate that the group had already diversified by the late Westphalian.
The teeth of a well known late Palaeozoic cladodont chondrichthyan, “Cladodus” occidentalis from Russia, USA, and England are restudied and a new generic name, Glikmanius gen. nov., is proposed for this species. Yet another tooth−based species, formerly described as ?Symmorium myachkovensis, occurring on the Russian Platform and in Nebraska, is considered to belong to the newly erected genus. Although there is no direct evidence that Glikmanius possessed fin spines, the broad similarity between its teeth and those of Ctenacanthus compressus suggests it had a ctenacanthiform affinity. The possible relationships between Glikmanius, Cladodus sensu stricto, “Ctenacanthus” costellatus, and Heslerodus, are suggested. However, the proposition put forward by an earlier author that the teeth of Heslerodus might represent the lower jaw dentition of G. myachkovensis, is rejected. The overall resemblance of Glikmanius teeth and those of Cladoselache and Squatinactis is recognised as convergent.
Stellate patterns, called astrorhizae, occurring in some Paleozoic stromatoporoids are by most authors regarded as integral elements of these enigmatic fossils. The finding of stellate structures on epithecae of rugose corals from the Lower Carboniferous of Central Laos seems to support, however, the idea that astrorhizae in Paleozoic stromatoporoids may represent traces of foreign organisms.
A new record of the chondrichthyan hybodontoid genus Lissodus is presented from two localities within the Mississippian (Tournaisian) rocks of Ireland. Five morphotypes of the genus are described within each of which occurs morphological variance. Specimens recovered and described herein are from crinoidal limestones whose palaeoenvironments are interpreted as ranging from a moderately shallow high−energy carbonate shelf, to relatively deep off−shore. The richest fauna recovered from the high−energy carbonate shelf, contains all five morphotypes raising the possibility that they may have been derived from a single species of shark. A discussion on the relationship between the five morphotypes and other Carboniferous Lissodus teeth is offered and it is argued that although the morphotypes differ slightly from other Carboniferous Lissodus teeth, they may belong to a closely related species not formally named until additional evidence is obtained. A mouth reconstruction using the teeth recovered from the Lower Carboniferous of Ireland is proposed.
The revision of shark teeth from the Pennsylvanian black shales of central USA, ascribed to “Phoebodus heslerorum” Williams, 1985 and Symmorium reniforme Cope, 1893, shows that “Ph. heslerorum” is a junior synonym of “Cladodus” divergens Trautschold, 1879. This species belongs neither to Phoebodus nor to Cladodus, so a new genus Heslerodus is proposed. Very common, robust cladodont teeth with a deep labio−basal depression and two buttons, often referred to as S. reniforme, do not belong to the latter species, but to “Cladodus” occidentalis Leidy, 1859. The generic affinity of “C.” occidentalis is yet undetermined, but it is possible that it represents ctenacanthoids.
Limnogyrinus elegans (Fritsch) is the most primitive micromelerpetontid temnospondyl from the Upper Carboniferous of Nýřany, Czech Republic. Arecent revision of the taxon by Werneburg (1994) attributed to this species a skull in dorsal aspect which was significantly larger than any previously reported and showed evidence of snout elongation. Restudy of this specimen demonstrates it to be a skull, visible in ventral aspect, of a juvenile of Cochleosaurus bohemicus, a more primitive edopoid temnospondyl, which is frequent in the Nýřany assemblage. Werneburg’s diagnosis of Limnogyrinusis revised and the problems of constructing ontogenetic series are discussed.
The types of the species belonging to the fusulinid genera Schubertella and Eoschubertella were examined from publications and type collections. Eoschubertella in general possesses all the features of Schubertella and therefore is a junior synonym of the latter. However, the concept of Eoschubertella best describes the genus Schubertina with its type species Schubertina curculi. Schubertina is closely related to the newly established genus Grovesella the concept of which is emended in this paper. Besides Schubertella, Schubertina, and Grovesella, the genera Mesoschubertella, Biwaella are reviewed and three new species, Grovesella nevadensis, Biwaella zhikalyaki, and Biwaella poletaevi, are described. The phylogenetic relationships of all Pennsylvanian–Cisuralian schubertellids are also proposed. Barrel−shaped Grovesella suggested being the very first schubertellid that appears sometimes in the middle–late Bashkirian time. In late Bashkirian it is then developed into ovoid to fusiform Schubertina. The latter genus gave rise into Schubertella in early Moscovian. First Fusiella derived from Schubertella in late Moscovian, Biwaella—in early Gzhelian and Boultonia—in late Gzhelian time. Genus Mesoschubertella also developed from Schubertella at least in Artinskian, but may be in late Sakmarian.
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