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A new mitrate from the Lower Ordovician of southern France

The mitrocystitid mitrate Vizcainocarpus dentiger gen. et sp. nov. originates from the Lower Arenig of the Montagne Noire, France. Its distinctive features are two dorsal areas of polyplated integument, thorn-like projections on the postero-ventral head plates and a leftward-opening mouth. A preliminary cladistic analysis shows that V. dentiger is more derived than Chinianocarpos thorali and is the most primitive mitrocystitid with a differentiated centro-dorsal plate D12 and with the upper lip plate n rigidly incorporated in the skeleton.

Early Cambrian brachiopods from North Greenland

A silicified late Early Cambrian (early Toyonian) brachiopod assemblage is described from the Paralleldal Formation of Peary Land, central North Greenland. The fauna comprises Acareorthis profunda sp. nov., Pelmanella borealis gen. et sp. nov., Kutorgina cingulata, and Agyrekia aff. obtusa. The assemblage is comparable to faunas described from the Lower Cambrian (Botomian) of south Tien-Shan, Kirgizia, and the lower Middle Cambrian (Ordian) of New South Wales, Australia.

Anatomy and relationships of the pareiasaur Pareiasuchus nasicornis from the Upper Permian of Zambia

A well-preserved and newly prepared skull has enabled a critical re-evaluation of the genus Pareiasuchus (Reptilia; Pareiasauridae) and the species Pareiasuchus nasicornis. The skull is heavily ossified, deeply sculptured, akinetic and anapsid. The skull roof sutures are described for the first time. Most elements typical of basal amniotes are present; however, the postparietal is a single median ossification, the tabular is absent, and a ' supernumerary element' (possibly a modified cervical osteoderm) is present.

Postcranial morphology and locomotor behaviour of two early Eocene miacoid carnivorans, Vulpavus and Didymictis

The postcranial skeletons of two contemporaneous early Eocene carnivorans, the miacid Vulpavus and the viverravid Didymictis, are described and compared with behaviourally diverse small and medium-bodied extant carnivorans. Body mass estimates based on the cross sectional geometry of humeri and femora indicate that these two taxa were similar in size, estimates for both genera ranging from about 3.5 to 7.5 kg. It is argued that Vulpavus was well adapted for climbing and was possibly arboreal, with locomotor behaviours comparable to those of the coatimundi (Nasua).

Permian Supaia fronds and an associated Autunia fructification from Shanxi, China

Three new species of bipartite Supaia frond, one associated with an Autunia ovuliferous organ have been identified. S. shanxiensis sp. nov. from Central Shanxi is roughly similar in gross morphology to Supaia species from the Permian Hermit Shale of North America, but differs in the size, shape and othe features of the frond. It can also be distinguished by the pinnules having an entire margin, a faintly decurren base and being more closely spaced, and the venation consisting of a weak mid-vein. S. contracta sp.

Two Devonian mitrates from South Africa

The anomalocystitid mitrate Placocystella africana (Gydo and Voorstehoek shales, upper Emsian-lower Eifelian, Bokkeveld Group, Cape Province, South Africa) is redescribed. The internal anatomy of the head, the tail morphology and part of the nervous system are reconstructed for the first time. P. africana belongs to the family Allanicytidiidae, together with four other Silurian and Devonian species from Gondwana. The monophyly of the Allanicytidiidae is supported by cladistic analysis. A second mitrate from the upper Emsian of the Bokkeveld Group, Bokkeveldia oosthuizeni gen. et sp. nov.

The morphology and shell microstructure of the thecideidine brachiopod Ancorellina ageri from the Lower Jurassic of Argentina

Serial sectioning of complete shells of Ancorellina ageri enables the first description of dorsal valve internal morphology and shell microstructure. The diagnostic description by Mancenido and Damborenea (1990) is inadequate, as the supposedly diagnostic features of the Ancorellina hemispondylium are known to occur in the Aalenian thecidellinid Moorellina. However, the Ancorellina brachidium, consisting of a laterally supported bifurcating column, is currently unique in the Thecideidina. The early ontogeny conforms with the thecideid pattern.

Lower Cambrian cambroclaves (incertae sedis) from Xinjiang, China, with comments on the morphological variability of sclerites

Four species of cambroclave, an enigmatic group whose position within the Metazoa is unresolved, are described from the Lower Cambrian Yurtus Formation of western Xinjiang, China. Cambrodavus bicornis is similar to a number of previously described species, including C. absonus from approximately equivalent age strata of South Australia. As in many cambroclave taxa, morphological variability of individual sclerites appears to be considerable. Morphometric analysis of four populations of C.

First record of footprints of terrestrial vertebrates from the Upper Permian of the Cis-Urals, Russia

The first tetrapod footprints from the Upper Permian of Russia are identified as Anthichnium ichnosp., on the basis of a short track from the Severodvinskian Gorizont (upper Tatarian, uppermost Permian) of Kulchomovo, 75 km east-north-east of Orenburg, southern Pre-Urals basin. The footprints are preserved in a ripple-marked sandstone unit, and appear to show an animal swimming, then crawling through wet marginal sediment, and finally moving on to firmer substrate. The sedimentary setting is an enclosed semi-arid foreland basin, close to high mountains.
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