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Five types of brachiopod-bivalve assemblages occur in Terebratula Beds and in the lower part of the Karchowice Beds (Middle Triassic, Muschelkalk) from the Strzelce Opolskie Quarry (Upper Silesia). These are: (1) Brachiopod coquina Assemblage dominated by the terebratulid brachiopod Coenothyris vulgaris; (2) Crumpled/Wavy Limestone Assemblage including bivalves and brachiopods; (3) Bivalve Coquina Assemblage dominated by pseudocorbulid bivalves; (4) Hardground Assemblage dominated by the brachiopod Tetractinella trigonella; and (5) Crinoid Limestone Assemblage dominated by crinoid columnals and the brachiopod Punctospirella fragilis. The distribution of the assemblages correlates with the eustatically-controlled lithological variation in the carbonate- dominated sequence of the Upper Silesian Muschelkalk. The brachiopod coquinas are parautochtonous remnants of terebratulid banks which thrived during the high bioproductivity but low oxygen conditions. Those conditions were caused by the biogenic influx generated from the terrains flooded during the Middle Triassic transgression. During the regressive phase, that resulted in the gradual decrease in bioproductivity and parallel increase in oxygen levels, the terebratulid banks were replaced by pseudocorbulid banks. With the further regression - and thus, the further increase in oxygen level - pseudocorbulid banks were replaced by the assemblages indicative of well-oxygenated oligotrophic environments (Hardground and Crinoid Limestone Assemblages). The observed changes in the faunal composition reflect mainly differences in metabolism and feeding strategy among dominant taxa.
The evolutionary changes of the Early Cretaceous (Valanginian) marine gastropod Rissoina (Buvignieria) sp. from Wąwał (central Poland) show a pattern typical of the Ancient Lake Concept. Its morphology is stable during period of unstable conditions and starts to change gradually when the environment becomes stable. The linear character of the evolutionary changes of Rissoina sp. and lack of evolution among co−occuring gastropods suggests that the rate of evolution was controlled by intrinsic factors, not the environment.
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Cope's rule concerns only the radiation phase of a clade, overlooking the phase of the clade decline; thus it is incomplete. Changes of body size during the entire evolutionary history of a clade are exemplified here by three trilobite groups - Ptychopariina, Asaphina and Phacopida. Increasing diversity of the clade is associated with increase in maximum body size during the radiation phase, and decreasing diversity is generally associated with a decrease in maximum body size. Two basic patterns of the maximum body size changes are observed during the decline of the clade. The first one is characterized by a high correlation between diversity and the maximum body size, and indicative of species attrition that is nonselective with respect to the body size. The second one is characterized by a weak correlation between diversity and maximum body size, and typical of selective species attrition in relation to size.
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Middle Triassic ammonoids from Silesia, Poland

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A description of new ammonoid specimens (Acrochordiceras aff. damesi, cf. Acrochordiceras sp. indet., Discoptychites cf. dux, ?Paraceratites sp., cf. Balatonites sp. indet., Beneckeia buchi) from the Lower Muschelkalk (Anisian, Middle Triassic) of Silesia (southern Poland) is presented. The detailed stratigraphic position of the new finds is given. The description is supplemented with a list of all species of ammonoids found hitherto in Silesia, which was a southern part of the Germanic Basin during the Anisian. Beneckeia and Noetlingites were typical of epicontinental seas and usually appeared in the early part of transgressions. Other ammonoids entered from the Tethys into the epicontinental sea of the Germanic Basin during the maxima of transgressions. Some of them (balatonitids, paraceratitids, bulogitids, Discoptychites and probably Acrochordiceras) were successful colonizers which established their own populations in the Germanic Basin and evolved towards morphologies typical of epicontinental seas. Other (Beyrichites sp., Paraceratites binodosus, and 'Trachyceras' sp.) are regarded as unsuccessful immigrants or empty shells drifted post-mortem from the Tethys.
In this review paper the environmental aspect which surrounds the road engineering objects is presented. The main road engineering objects are: roads, bridges, tunnels and the resistance constructions. This paper presents also law requirements for design and building roads’ engineering objects. Every stage of environmental element has been followed. The infl uence between road and the surrounding is analyzed. The algorithm for the environmental analysis of roads designing and building is also presented.
This is a second paper dealing with juvenile and little known Mesozoic gastropods from Siberia and the Timan region. This part contains description of gastropods belonging to Neogastropoda and Heterobranchia. Described are 16 species, five of them are new. They are: Sulcoactaeon uralicus, S. timanicus, S. bojarkensis (Bullinidae), Vasju- gania vasjuganensis (Acteonidae), and Biplica siberica (Ringiculidae). The new genus Vasjugania (Acteonidae) is proposed. Eight species are left in the open nomenclature. The protoconch of Siberian Khetella, illustrated here for the first time, suggests that this genus belongs to Purpurinidae and the whole family is a possible stem group for the Neogastropoda. Apart from Khetella the Siberian fauna seems to be of cosmopolitan character having common elements both with Europe and North America.
The Campanian (Upper Cretaceous) seep carbonate at Omagari (Hokkaido, Japan) yields a monospecific association of the terebratulide brachiopod Eucalathis methanophila Bitner sp. nov. The association is the only occurrence of brachiopods known from the post−Early Cretaceous history of chemosynthesis−based communities. Unlike many earlier rhynchonellide−dominated hydrocarbon seep associations—which disappeared in Aptian times—this association is composed of chlidonophorid terebratulides. It is hypothesised here that large rhynchonellide brachiopods have been outcompeted from chemosynthesis−based associations by large chemosymbiotic bivalves (especially lucinids) and that this seep association containing numerous terebratulide brachiopods originated as a result of immigration from the background fauna settling in a seep that lacked numerous large bivalves but offered some hard substrates for brachiopod attachment. Some living chlidonophorids are known to settle around seep/vent localities or more generally in deep−water hard−substrate settings. We review occurrences of brachiopods in chemosynthesis−based associations and show that brachiopods immigrated repeatedly to seep/vent environments. Eucalathis methanophila Bitner sp. nov. represents the oldest and single Mesozoic record of the genus. The new species is similar in ornamentation to three living species, Indo−Pacific E. murrayi, eastern Atlantic E. tuberata, and Caribbean E. cubensis but differs in having a higher beak and wider loop. Additionally the studied species is nearly twice as large as E. tuberata.
Sixteen gastropod species from two Campanian (Upper Cretaceous) hydrocarbon seep localities in Hokkaido, Japan are described. Seven species are new: the acmaeid limpet Serradonta omagariensis; three turbinids: Homalopoma abeshinaiensis, Cantrainea yasukawensis, and C. omagariensis; the trochid Margarites sasakii; the seguenzioid Cataegis nakagawensis; and the provannid Provanna nakagawensis. The most common species in the investigated localities are acmaeid limpets (S. omagariensis), tiny turbinids (H. abeshinaiensis, C. yasukawensis, C. omagariensis), and provannids/hokkaidoconchids (P. nakagawensis and Hokkaidoconcha hikidai). The Upper Cretaceous associations described here do not resemble Lower Cretaceous associations known from other regions but are composed of species similar to gastropods from Recent hydrocarbon seeps and hydrothermal vents in the Northwestern Pacific. This strongly suggest that this region possesses a regional pool of gastropods in chemosynthesis−based communities at least since Late Cretaceous time. The only group of gastropods described here which has no Recent counterpart is the Hokkaidoconchidae. A comparison to gastropods from plesiosaur falls and sunken wood of the same age and region strongly suggest that these invertebrate communities do not differ significantly from the coeval hydrocarbon seep communities described herein.
Two Campanian methane seep sites in the Nakagawa area of Hokkaido (northern Japan) yield fossils of the limpet genera Serradonta and Bathyacmaea that appear to have had the same substrate preference as do their modern counterparts. Serradonta cf. vestimentifericola was a species having an elongated and strongly compressed shell adapted to living on vestimentiferan tubes, like its modern relatives. Bathyacmaea cf. subnipponica was an acmaeid with a relatively elongated shell but with a more rounded aperture than Serradonta and thus apparently attached to small hard objects other than worm tubes. One Bathyacmaea specimen was found attached in situ to an ataphrid gastropod shell. The restricted present−day distribution of Serradonta possibly reflects its spreading route exclusively through the hot vent and cold seep communities settled by vestimentiferans.
The objective of this report is to document first Mesozoic occurrences of chemosynthesis−based communities developed on large marine reptile carcasses. Micro−grazing provannid gastropods (typical of chemosynthetic communities) are associated with plesiosaurid skeletons in the Upper Cretaceous deposits of Hokkaido, northern Japan. The cancellous bones of the examined plesiosaurid bones contain a ubiquity of iron sulfides within the bone trabeculae, which provides evidence of anaerobic sulfate reduction of the bone lipids. We also report numerous microborings in the bone trabeculae, which might result from the activity of sulfur−oxidizing bacteria. This finding addresses the hotly debated problem of the emergence and radiation of whale bone faunas. We postulate that vertebrate bone environments in the Northwest Pacific region were settled repeatedly by animals from a regional pool of chemosynthesis−based communities that flourished in the methane seeps and/or hot vents that were present during the Late Cretaceous–Miocene.
Exceptionally well preserved specimens of the bivalve mollusc Modiola major were collected from a Lower Cretaceous (Barremian) hydrocarbon seep deposit in northern California. This material, together with the type series of M. major, and various other specimens from Upper Jurassic to Lower Cretaceous seep localities in California, is redescribed and referred to the hydrocarbon seep−restricted modiomorphid genus Caspiconcha. We include also a description of Myoconcha americana because some previous reports have incorrectly synonymized Myoconcha americana with Caspiconcha major. In addition, we report Caspiconcha sp. from a Lower Cretaceous (Albian) hydrocarbon seep from Hokkaido, Japan, and we review all currently described species of Caspiconcha, and other species that probably belong to this genus. We demonstrate that Caspiconcha had a widespread distribution in Late Jurassic to Early Cretaceous hydrocarbon seeps, but became rare thereafter, with the last representative occurring in Upper Cretaceous strata of Japan. This macroevolutionary pattern is similar to that observed in the seep−restricted brachiopods. After the decline of Caspiconcha at the end of the Early Cretaceous and its last occurrence in the Campanian, the ecological niche of epifaunal to semi−infaunal seep endemic bivalves was largely vacant and not reoccupied until the Eocene with the appearance of the vesicomyid and bathymodiolin bivalves. The formal placement of M. major into the genus Caspiconcha restricts the fossil record of mytilids at seeps to post−Mesozoic times, and thus there is less discrepancy between the fossil record of chemosynthetic mytilids and their divergence age estimates from molecular data.
We present a systematic study of late Paleocene macrofauna from methane seep carbonates and associated driftwood in the shallow marine Basilika Formation, Spitsbergen, Svalbard. The fauna is composed of 22 taxa, comprising one brachiopod, 14 bivalves, three gastropods, three crustaceans, and one bony fish. The reported fish remains are among the first vertebrate body fossils from the Paleogene of Spitsbergen. One genus is new: the munidid decapod Valamunida Klompmaker and Robins gen. nov. Four new species are described: the terebratulide brachiopod Neoliothyrina nakremi Bitner sp. nov., the protobranch bivalve Yoldiella spitsbergensis Amano sp. nov., the xylophagain bivalve Xylophagella littlei Hryniewicz sp. nov., and the munidid decapod Valamunida haeggi Klompmaker and Robins gen. et sp. nov. New combinations are provided for the mytilid bivalve Inoperna plenicostata, the thyasirid bivalve Rhacothyas spitzbergensis, the ampullinid gastropod Globularia isfjordensis, and the munidid decapod Protomunida spitzbergica. Thirteen taxa are left in open nomenclature. The fauna contains a few last occurrences of Cretaceous survivors into the Paleocene, as well as first occurrences of Cenozoic taxa. It is composed of chemosymbiotic thyasirid bivalves and background species common in the northern Atlantic and Arctic during the Paleocene. Our results provide no evidence for a Paleocene origin of vesicomyid and bathymodiolin bivalves typical for Eocene and younger seep environments; instead, the Paleo cene seeps of the Basilika Formation are more similar to their Late Cretaceous equi valents rich in thyasirids.
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