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Three specimens of the small breviconic ellesmeroceratid Paradakeoceras minor Flower, 1964 from the Tremadocian of the New York area preserve the annular elevation and muscle scars in moulds of the body chamber. The annular elevation is positioned at the base of the body chamber and is wider on the convex side of the shell than on the concave side. Multiple paired muscle scars can be seen within this annular elevation. A well-preserved body chamber of the breviconic ellesmeroceratid Levisoceras cf. edwardsi Ulrich, Foerste and Miller is described.

• Read more about Some lesser known features of the ancient cephalopod order Ellesmerocerida (Nautiloidea, Cephalopoda)

The two plesiosauroid species from the Posidonia shale of Holzmaden, 'Plesiosaurus'guilelmiimperatoris and 'Plesiosaurus'brachypterygius, do not belong to Plesiosaurus but form new monotypic genera. The new genus Hydrorion is erected for 'P.'brachypterygius, and the genus Seeleyosaurus is re-established for 'P.'guilelmiimperatoris. The recently described species Plesiopterys wildii is regarded as a junior synonym of S. guilelmiimperatoris. A short phylogenetic analysis shows that S. guilelmiimperatoris and Muraenosaurus are basal elasmosaurs. H.

• Read more about The taxonomic and phylogenetic position of the Plesiosauroidea from the Lower Jurassic Posidonia Shale of south-west Germany

Current models for the exceptional preservation of Burgess Shale fossils have focused on either the HF-extractable carbonaceous compressions or the mineral films identified by elemental mapping. BSEM, EDX and microprobe analysis of two-dimensionally preserved Marpolia, Wiwaxia and Burgessia identifies the presence of both carbonaceous and aluminosilicate films for most features, irrespective of original lability.

• Read more about Fossil diagenesis in the Burgess Shale

Currently the beetle family Coptoclavidae consists of four subfamilies known from the Upper Triassic-Lower Cretaceous (Aptian). We describe two new subfamilies, three new genera and five new species from the Las Hoyas (Cuenca Province) and El Montsec (Lleida Province) localities of Barremian (Early Cretaceous) age from Spain: the first new subfamily, Hispanoclavinae, is from Las Hoyas and comprises one new genus, Hispanoclavina, and two new species, H. diazromerali and H. gratshevi; the second, Coptoclaviscinae, is represented at El Montsec by one new species of Coptoclavella (C. inexpecta).

• Read more about Coptoclavid beetles (Coleoptera: Adephaga) from the Lower Cretaceous of Spain: a new feeding strategy in beetles

New fossil remains of the anthracothere genus Merycopotamus Falconer and Cautley, are described. Most of them were discovered by the Harvard University and Geological Survey of Pakistan joint research project (Y-GSP) in the well-dated Middle and Late Miocene deposits of the Potwar Plateau in northern Pakistan. This new material led us to revise the systematics of the genus with the validation of three species, M. nanus Falconer (M. pusillus Lydekker), M. dissimilis Falconer and Cautley, and M.

• Read more about Anatomical revision of the genus Merycopotamus (Artiodactyla; Anthracotheriidae): its significance for Late Miocene mammal dispersal in Asia

In Ordovician ostracodes (genus Incisua) a new kind of sexual dimorphism is described, which is the first example among this group with males being the heteromorphs. The valves of males are larger and less frequent than the females, and are characterized by having a furrow in the ventral part. The furrow may have functioned as a device to enable the two sexes to cling together during mating.

• Read more about A new kind of sexual dimorphism in Ordovician ostracodes

A bryozoan fauna from carbonate mud-mounds is described from subsurface well cores from the Upper Ordovician (Lower Ashgill) Jifarah (Djeffara) Formation of Tripolitania, north-west Libya. Among a diverse assemblage dominated by trepostomes, nine species of bryozoans are identified, including Jifarahpora libyensis gen. et sp. nov. Delicate and robust branching, encrusting and nodular bryozoan growth forms are all common.

• Read more about Bryozoan mud-mounds from the Upper Ordovician Jifarah (Djeffara) Formation of Tripolitania, north-west Libya

Forty-five specimens of Leptomitus conicus sp. nov. have been collected from the base of the Murero Formation (Caesaraugustan, Middle Cambrian) in the Murero area of Zaragoza, north-east Spain. The new species is a small obconical sponge, which has coarse oxeas forming parallel rods that run the whole length of the specimens in the manner typical of the genus. The biostratigraphy and facies of the levels with Leptomitus conicus have been analysed. Palaeoecological information derived from associated trilobites, brachiopods and ichnofossils shows that L.

• Read more about The demosponge genus Leptomitus and a new species from the Middle Cambrian of Spain

This paper describes the diversity, taphonomy and palaeoecology of angiosperm leaves that dominate a palaeoflora of Cretaceous (Cenomanian-Coniacian) age from the Mata Amarilla Formation in the Austral Basin, south-west Patagonia, Argentina. Twelve morphotypes of angiosperm leaves are recognized based on foliar morphotype analysis of more than 500 specimens. These were divided into six morphological groups based on major architectural patterns.

• Read more about Diversity, taphonomy and palaeoecology of an angiosperm flora from the Cretaceous (Cenomanian–Coniacian) in southern Patagonia, Argentina

We re-examine the type series of 'Sinemys'wuerhoensis Yeh (at least 20 specimens, including several shells and skulls on three slabs of matrix and one isolated skull) from the Early Cretaceous Tugulu Group of China. Our study shows that the type series of 'S.'wuerhoensis is actually a chimera made up of at least three distinct taxa. The holotype of this taxon should be assigned to the basal eucryptodire genus Xinjiangchelys Yeh. As there are no characters that distinguish 'S.'wuerhoensis from Xinjiangchelys species, we consider it to be a nomen dubium.

• Read more about The type series of 'Sinemys' wuerhoensis, a problematic turtle from the Lower Cretaceous of China, includes at least three taxa