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The crystallographic orientation of structural elements in skeletons of representatives of Carboniferous Syringoporicae (Auloporida) has been analysed by scanning electron microscopy (SEM), petrographic microscopy and electron backscatter diffraction (EBSD) on specimens from the Iberian Peninsula. The skeletons of the tabulate corals of the Syringoporicae consist of biogenic calcite crystals, and their microstructure is composed of lamellae, fibres and granules, or of a combination of these.

• Read more about Crystallographic orientations of structural elements in skeletons of Syringoporicae (tabulate corals, Carboniferous): implications for biomineralization processes in Palaeozoic corals

New fossil mammals found at the base of Acantilados II Allomember of the La Meseta Formation, from the early Eocene (Ypresian) of Seymour Island, represent the oldest evidence of this group in Antarctica. Two specimens are here described; the first belongs to a talonid portion of a lower right molar assigned to the sparnotheriodontid litoptern Notiolofos sp. cf. N. arquinotiensis. Sparnotheriodontid were medium- to large-sized ungulates, with a wide distribution in the Eocene of South America and Antarctica.

• Read more about The oldest mammals from Antarctica, early Eocene of the La Meseta Formation, Seymour Island

The genus Agriopleura (Radiolitidae) is restricted to the Lower Cretaceous of the Mediterranean region, including the Middle East, and this rudist is apparently absent from the New World. Agriopleura underwent a size increase from late Hauterivian to mid-late Barremian, matching Cope's rule, followed by a Lilliput phase in the early Aptian. The relative development of radial bands increased through time and represents a key evolutionary index.

• Read more about Evolution of the rudist bivalve Agriopleura Kühn (Radiolitidae, Hippuritida) from the Mediterranean region

Interpretation of the enigmatic soft-bodied yunnanozoans from the Lower Cambrian (Stage 3, Series 2) Chengjiang Biota has remained controversial for decades because of their strange body plan and their variable taphonomic alteration. Proposed affinities have ranged from stem bilaterian to stem vertebrate. A study of over seven hundred slabs, many newly collected, from five sections at two localities demonstrates that yunnanozoans have sclerotized dorsal and axial segments, a body cavity, a unique feeding region and a coiled alimentary canal.

• Read more about New data on the palaeobiology of the enigmatic yunnanozoans from the Chengjiang Biota, Lower Cambrian, China

Calibration of the divergence times of sponge lineages and understanding of their phylogenetic history are hampered by the difficulty in recognizing crown versus stem groups in the fossil record. A new specimen from the lower Cambrian (Series 2, Stage 3; approximately 515 Ma) Sirius Passet Biota of North Greenland has yielded a diagnostic spicule assemblage of the extant demosponge lineages Haploscleromorpha and/or Heteroscleromorpha.

• Read more about A crown-group demosponge from the early Cambrian Sirius Passet Biota, North Greenland

The interrelationships and evolutionary history of molluscs have seen great advances in the last decade. Recent phylogenetic studies have allowed alternative morphology-based evolutionary scenarios to be tested and, most significantly, shown that the aplacophorans are sister group to polyplacophorans (chitons), corroborating palaeontological and embryological evolutionary scenarios in which aplacophorans are secondarily simplified from a chiton-like ancestor. Aplacophoran morphology therefore does not represent the plesiomorphic condition for molluscs as a whole.

• Read more about The origins of molluscs

The evolution of eukaryotes represents one of the most fundamental transitions in the history of life on Earth; however, there is little consensus as to when or over what timescale it occurred. Review of recent hypotheses and data in a phylogenetic context yields a broadly coherent account. Critical re-assessment of the palaeontological record provides convincing evidence for the presence of crown-group eukaryotes in the late Palaeoproterozic, and stem-group eukaryotes extending back to the early Archaean.

• Read more about Early evolution of the Eukaryota

This study, the third in the series of virtual issues of Palaeontology, examines the contributions the journal has made to the field of palaeobotany from 1961 onwards. I offer a personal selection of six papers representing four decades of research, with a range of specific geographical (Canada, Australia, China), temporal (Mesozoic, Devonian, Silurian) or more general (cycads, palynology, stratigraphy) focus.

• Read more about A palaeobotanical pot-pourri

No Abstract.

• Read more about Volume and Author Index

Hindeodus parvus and Hindeodus typicalis occur in a deep-water chert and claystone section in the Mino Terrane, Japan, which has been identified as a Jurassic accretionary complex. Conodont fossils are preserved as natural assemblages of impression fossils on bedding planes in claystone. In this study, 13 assemblages of Hindeodus species were recognized, comprising at most 13 elements which generally maintain the original composition and structure of an apparatus.

• Read more about Natural assemblages of Hindeodus conodonts from a Permian–Triassic boundary sequence, Japan