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Brachiopods of the orders Strophomenida, Orthotetida, and Athyridida from the late middle Frasnian–early Famennian interval (hassi to triangularis conodont zones) in the Namur-Dinant Basin (southeastern margin of Laurussia; southern Belgium) are described. Nine genera and subgenera represented by 12 species are recognized here. One new genus, Retrorstrophia, and one new species, Douvillina area, are erected. Crinisarina stainbrooki is proposed to solve the homonymy between C. reticulata (Gosselet, 1877) and Cleiothyridina reticulataStainbrook, 1947, the type species of CrinisarinaCooper and Dutro, 1982. A lectotype is selected and illustrated for C. reticulata. A new name is also proposed for Athyris reticulataChen and Xu, 2000, which is assigned here to Crinisarina: C. shashishanensis nom. nov. In southern Belgium, the last representatives of the families Douvillinidae and Leptostrophiidae (Strophomenida) are from the Upper rhenana Zone (late Frasnian). Athyridid brachiopods, especially the representatives of the subfamily Cleiothyridininae constituted a significant part of the early Famennian recovery faunas with spiriferids and rhynchonellids, just after the late Frasnian mass extinction.
We present a critical review of the alpha taxonomy and evolution of Eocene North American paromomyid primates, based on analysis of more than 570 stratigraphically controlled dental and gnathic specimens from the early Eocene of the southern Bighorn Basin, Wyoming (Wasatchian, Willwood Formation). In addition to documenting numerous previously unpublished specimens of known taxa (including deciduous teeth), we also describe a new species, Phenacolemur willwoodensis n. sp., from the upper part of the Willwood Formation (Wa 5 and 6). The new species is intermediate in size between Phenacolemur simonsi and Phenacolemur citatus and has both primitive features (e.g., retention of m2–3 paraconids, relatively long molar trigonids) and derived traits (e.g., relatively reduced paraconid on m1 and no p4 paracristid, unlike Paromomys). Overall patterns of dental evolution in southern Bighorn Basin paromomyids provide some support for previously hypothesized periods of faunal change (Biohorizons). In particular, Phenacolemur praecox evolves into the similarly sized but morphologically distinct Phenacolemur fortior at Biohorizon A, and P. fortior is replaced by P. citatus just below Biohorizon B. Two taxa previously believed to have become extinct at Biohorizon A (Ignacius graybullianus, P. simonsi) are shown to have persisted about a million years longer than previously thought. The Bighorn Basin paromomyids are of general interest in comprising a very dense sample that allows for the study of patterns of evolution against the backdrop of well-understood patterns of change in other mammalian lineages, and in climatic variables.
Black shales of the Coroico Formation are part of a thick succession of Lower and Middle Ordovician strata that were deposited in the Cordillera Oriental foreland basin along the margin of West Gondwana. The basin was inhabited primarily by a cool-water, Atlantic-type graptolite fauna. Newly discovered material from rocks that crop out near the town of Consata in NW Bolivia include unexpected warm-water or Pacific-type elements such as Parisograptus caduceus and Pseudotrigonograptus within an assemblage dominated by abundant pendent Didymograptus specimens, Cryptograptus schaeferi, and diplograptaceans such as Oelandograptus oelandicus and Hustedograptus bulmani n. sp. Parisograptus caduceus has generally been considered to be restricted to oceanic depths below those of the epipalagic realm that occupied continental shelves, whereas the remainder of the assemblage is more characteristic of relatively shallow water, epicratonic sites. We interpret this mixed assemblage to be the Atlantic Province, West Gondwanan equivalent of the off-shore isograptid biofacies that is much more widely known from low latitude sites around the globe. These results suggest that in this region of West Gondwana, the properties of local water masses (productivity and physical features such as temperature, salinity, or oxygenation) strongly influenced graptolite species distribution and led to biofacies differentiation among coeval assemblages. It also suggests that some isograptids inhabited the epipelagic biotope in mid to high latitude regions. The new species Hustedograptus bulmani is described herein.
A bone bed in the middle part of the Javelina Formation (Maastrichtian) in Texas yielded parts of about 37 identifiable ceratopsid dinosaur bones, mostly appendicular and limb girdle elements belonging to one juvenile and two adult individuals of Torosaurus cf. utahensis. The bone bed is a lag assemblage comprising large immobile parts of the skeletons accumulated in an abandoned stream channel. In general form and proportions the postcranial bones are similar to those in Pentaceratops sternbergi and are not as robust as those in Torosaurus latus or Triceratops horridus. A few cranial elements are preserved, including parts of a parietal, squamosal, maxilla, and two dentaries. The form of the parietal fragment is comparable to that of a more nearly complete specimen of Torosaurus cf. utahensis collected nearby at about the same stratigraphic level. The bone bed material provides a basis for the first skeletal reconstruction of this enigmatic horned dinosaur. Most characters used in diagnoses of T. utahensis and T. latus are inadequate. Only the raised bar along the squamosal/parietal suture, present in T. latus; and the midline epiparietal, absent in T. latus, may discriminate the two species.
Bivalves from the Late Devonian pelagic or Hercynian Facies of classical regions such as eastern North America and Europe have not been investigated for almost a century.
A group of small, radially ribbed bivalves frequently occurs in association with ammonoids and conodonts in pelagic cephalopod limestones and shales of the latest Frasnian and early Famennian. These bivalves have traditionally been assigned to the Late Silurian genus PraecardiumBarrande, 1881. Re-studying the types of the Late Devonian taxa, Cardium? vetustumHall, 1843, Cardiola duplicataMünster, 1840, Praecardium clymeniaeBeushausen, 1895, Praecardium melletesClarke, 1904, and Praecardium multicostatumClarke, 1904 shows that they differ significantly from Praecardium.
As a result, two new genera, Vetupraeca n. gen. and Mucopraeca n. gen, are established. Furthermore, neotypes are designated for Cardiola nehdensis, Kayser, 1873 and Vetupraeca clymeniae (Beushausen, 1895), and lectotypes are chosen for Mucopraeca multicostata (Clarke, 1904) and Vetupraeca duplicata (Münster, 1840). These bivalve taxa were widely distributed in the subtropical to tropical, latest Frasnian/early Famennian outer shelf habitats of Laurussia and Gondwana.
Based on a thorough examination of field and museum Climactichnites specimens, two species of this trace are recognized, each representing a unique behavioral variant produced by a soft-bodied animal in Late Cambrian intertidal environments. C. wilsoni represents surface-produced trails, whereas C. youngi is re-erected for burrows produced below the surface. Burrowing behavior is supported by: 1) the presence of C. youngi within, rather than on, the surface of beds; 2) the orientation of some burrows inclined to bedding; and 3) the occasional presence of distinct burrow fills. Burrows can also be distinguished morphologically from surface traces by the absence of lateral ridges and the presence of fine, mm-scale striations or grooves superimposed on the transverse bars and furrows. Burrowing behavior for the Climactichnites trailmaker was previously unknown and thus represents a new, although not entirely unexpected, behavior for this mollusk or mollusk-like animal. The body impression of the sedentary animal is removed to Musculopodus sedentarius n. igen. and isp. In the future, Musculopodus may be expanded to include the resting traces of other soft-bodied animals known from the fossil record. Currently, Climactichnites is known only from very shallow to emergent strata of North America; reports of this fossil in other parts of the world are misidentified trails produced by other animals.
Three fossil taxa of megapodagrionid damselflies are described and figured from the Paleogene localities in Europe on the basis of isolated wings. Eckfeldia superstes (Wappler, 2003) gen. nov. is described from the laminated mudstones of middle Eocene age from Eckfeld Maar, Germany. Furagrion jutlandicus (Henriksen, 1922) gen. nov. is recorded from the laminated claystones of lowermost Eocene age from the Ølst and Fur-Formation, Denmark, and an undetermined megapodagrionid damselfly is recognized from middle Eocene strata. Taphonomy and color preservation in the fossils are briefly considered. Characters used for phylogenetic analyses in extant and fossil Megapodagrionidae are discussed. The biogeographic and paleoecological implications of the new European fossils are briefly discussed.
Crowns of four crinoid species, Talarocrinus planusWeller, 1920, Phacelocrinus longidactylus (McChesney, 1860), Ampelocrinus mundus? Kirk, 1942, and Phanocrinus maniformis (Yandell and Shumard, 1847) are reported from the limestones of the Wymps Gap Member of the Greenbrier Formation in northern West Virginia. Collectively these species indicate an early Chesterian age for the Wymps Gap Member, with the occurrence of T. planus indicating correlation with the Ridenhower (Paint Creek) Formation of the Illinois Basin. A review of the 17 species currently placed in Talarocrinus suggests that the Talarocrinus zone ranges no higher than the Ridenhower Formation in the Upper Gnathodus bilineatus conodont zone of the late Visean. The new occurrence of A. mundus extends its range upwards from the Genevievian substage of the Chesterian.
Previous studies have used sequence stratigraphy to correlate the Wymps Gap Member with the lower part of the Union Limestone Formation of the Greenbrier Group in southern West Virginia, which in turn has been correlated with the Ridenhower Formation. The occurrence of T. planus in the Wymps Gap Member provides independent confirmation of the correlations based on sequence stratigraphy between the Appalachian and Illinois basins. Correlation of the overlying Reynolds Member of the Mauch Chunk Formation with the Glen Dean Formation of the Illinois Basin suggests a significant unconformity between the Greenbrier Formation and Mauch Chunk Formation in northern West Virginia.
Upper Carboniferous and Lower Permian shallow marine rocks in the Pequop Mountains of northeastern Nevada contain an abundance of fossils, especially fusulinids and fasciculate corals. As the composite stratigraphic section in this area represents the most nearly complete sequence of this type of corals anywhere in the Cordilleran miogeocline, this study was undertaken to document their occurrence sequentially. This information should be useful for comparison with other sections in the miogeocline containing similar corals.
Only one species of Durhamina is present in the Gzhelian rocks. Durhamina, Heintzella, and Paraheritschioides occur in the Asselian rocks, and all of these genera plus Wilsonastraea are present in the Sakmarian part of the section. Corals in the Artinskian and Kungurian are represented by an advanced species of Durhamina and the very advanced durhaminid, Sandolasma.
Newly described species are: Durhamina primitiva, D. snyderi, Sandolasma perplexa, Heintzella davydovi, Paraheritschioides nevadaensis, and Wilsonastraea fraseri.