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Revision and re-evaluation of the Early Jurassic dinosaurian ichnogenus Otozoum

Otozoum moodii Hitchcock, 1847 is one of the classic Connecticut Valley ichnotaxa established by Edward Hitchcock between 1836 and 1865. The taxon is redescribed, and AC 4/1a re-established as the holotype specimen. Otozoum minus and O. caudatum are synonymised with O. moodii. The syntypes of Kalosauropus pollex (nomen nudum) are described as O. pollex sp. nov. Cladistic, quantitative, and comparative methods of trackmaker identification suggest that Otozoum was made by a prosauropod dinosaur.

The Middle Jurassic flora from Stonesfield, Oxfordshire, UK

The Stonesfield 'Slate' of Oxfordshire has yielded a diverse Middle Jurassic flora, containing 25 morphospecies, dominated by remains of araucariacean and cheirolepidiacean conifers, bennettitaleans, and leaves of the possible gymnosperm Pelourdea. It mainly represents coastal vegetation, which included mangrove-like stands of Ptilophyllum, and conifers probably growing in lowland coastal habitats that were subjected to periodic water-stress. The Pelourdea leaves may have drifted in from drier, more upland habitats.

Wasatchian (early Eocene) pollen floras from the Red Hot Truck Stop, Mississippi, USA

Sediments at the Red Hot Truck Stop (RHTS), Mississippi, USA are important because they contain the lowest latitude record of both the earliest known Eocene plant and mammal fossils in North America. The RHTS contains the uppermost Tuscahoma Formation and the lowermost part of the basal Bashi and Hatchetigbee formations. The Tuscahoma Formation is composed of glauconitic sands and silts that represent estuarine to shallow marine sediments.

Evolutionary morphology of oblique ribs of bivalves

Fossil bivalves bearing oblique ribs first appeared in the Mid Ordovician but their diversity remained low during the Palaeozoic. The diversity soon increased after the Early Triassic, peaking in the Early Cretaceous. The Palaeozoic-Mesozoic record is dominated by burrowing bivalves (mainly pholadomyoids and trigonioids), which developed oblique ribs with symmetric profiles, probably adapted for shell reinforcement, although there are indications that the ribs of trigonioids also enhanced burrowing efficiency.

Llanvirn (Middle Ordovician) echinoderms from Llandegley Rocks, central Wales

A diverse Llanvirn echinoderm fauna is described from nearshore volcanogenic sandstones of Llandegley Rocks, Builth-Llandrindod Inlier, Powys. The fauna comprises six crinoids (including Cefnocrinus samgilmouri gen. et sp. nov., Iocrinus llandegleyi sp. nov.), three asteroids and one cystoid; at least two indeterminate crinoids and one asteroid represent undescribed taxa, but yielded insufficient material for formal description. Two complex radical root structures are among the oldest recorded examples.

Amphibian swimming traces from the Lower Permian of southern New Mexico

Fossilised traces of swimming amphibians, assigned to Batrachichnus delicatulus and Serpentichnus robledoensis igen. et isp. nov., are described from the Lower Permian of the Robledo Mountains, southern New Mexico. The B. delicatulus specimen is interpreted as a trackway of a small 'amphibian' (temnospondyl, nectridean, microsaur or juvenile embolomere) swimming straight ahead. S. robledoensis consists of repeated pes imprints separated by discontinuous, L-shaped imprints (body traces).

A Mid Devonian seed-megaspore from East Greenland and the origin of the seed plants

A new species of late Mid Devonian seed-megaspore from East Greenland is described and named as Spermasporites allenii. The formerly monotypic genus Spermasporites is emended to accommodate this new species. Rare specimens of S. allenii, with near complete sporangial contents, occur together with specimens showing proximally adhering microspores. These demonstrate that S. allenii was contained within a sporangium exhibiting extreme anisospory, which is interpreted here as functionally bisexual. This is a key element in understanding its reproductive function.

The trilobite family Nileidae: morphology and classification

Species of genera currently referred to Nileidae are reviewed, and those of Hemibarrandia, Lakaspis, Peraspis and Symphysurina are excluded from the family. Nileidae are united in having a distinctive form of the hypostome, the glabellar organ, in the shallowness or absence of external furrows on the axial and pleural regions, and in the development of strong ventral ridges on the axial region.

Shell repair and mode of life of Praenatica gregaria (Gastropoda) from the Devonian of Bohemia (Czech Republic)

Repaired shell injuries occuring in less than four per cent of examined specimens of the platyceratid gastropod Praenatica gregaria (Barrande, in Perner 1903) from the Lower Devonian (Pragian) of Bohemia probably result from non-lethal predatory attacks. The low frequency may reflect the resistance of the large, smooth, rapidly expanding shell to attack, but a high rate of fatal attacks could produce the same pattern. The habit of some platyceratid gastropods living on echinoderm calices may provide a refuge from benthic predators, but conclusive evidence for this mode of life in P.

New information on cranial and dental features of the Triassic archosauriform reptile Euparkeria capensis

The course of the nasolacrimal duct, interdental plate morphology, and most details of tooth and denticle morphology have not previously been described in non-archosauriform reptilkes. Here I describe these details in the Triassic archosauriform Euparkeria capensis. The nasolacrimal canal opens orbitally via a pair of foramina between the lacrimal and prefrontal. The canal arches over the antorbital fenestra, as in archosaurs. The term 'interdental unit' is introduced for the unit composed of an interdental septum and its accompanying interdental plate.
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