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The number, outline and arrangement of muscle scars on the internal mould of the body chamber of five species of Early and Middle Ordovician nautiloids from Baltoscandia are described. The ellesmeroceratids Oelandoceras haelluddenense Foerste and Pictetoceras oliviae King have 9-10 pairs of muscle scars. The oncoceratid Phtanoncoceras ellipticum (Lossen), and Botellusoceras torpense gen. et sp. nov., order and family indeterminate, have eight and nine pairs of muscle scars, respectively. The tarphycerid Estonioceras imperfectum (Quenstedt) has four pairs of muscle scars.

• Read more about Nautiloids with multiple paired muscle scars from Lower–Middle Ordovician of Baltoscandia

Early Middle Ordovician graptolites from the Albjara and Lovisefred drill cores (Scania, southern Sweden) can be differentiated into the Isograptus victoriae, Isograptus sp. nov. 2 and Maeandrograptus schmalenseei, Arienigraptus dumosus type/Pseudisograptus manubriatus biozones of Castlemainian and Yapeenian age and the Arienigraptus zhejiangensis and Undulograptus sinicus biozones of early Darriwilian age, replacing the old, long-ranging Didymograptus hirundo Biozone. Faunas from the drill cores include a number of species not previously recognized in Scandinavia.

• Read more about Early Middle Ordovician graptolite biostratigraphy of the Lovisefred and Albjära drill cores (Scania, southern Sweden)

Syntrophiidine brachiopods are a rare and poorly known component of Ordovician Baltoscandian faunas. They appear in the East Baltic in the Billingenian (lower Arenig) as part of the earliest known benthic assemblages dominated by elements of the Palaeozoic Evolutionary Fauna. These faunal assemblages usually include bryozoans, ostracodes, and the earliest known porambonitoids, strophomenides and endopunctate orthides, such as Idiostrophia and Orthidium, which later became characteristic of the Whiterockian brachiopod assemblages in Laurentia, but by that time had disappeared from Baltica.

• Read more about Ordovician (Arenig–Caradoc) syntrophiidine brachiopods from the east Baltic region

The fossiliferous site of Mahenge, Tanzania, interpreted as a small lake that formed in a kimberlite intrusion, has yielded a vertebrate assemblage that includes scarce frog remains. Radiometric dating of the pipe indicates that the volcanic activity took place at 45.83 +/- 0.17 Ma, whereas infilling of the crater was completed in 0.2-1.0 myr after emplacement. The frogs, described herein, are preserved as partially articulated skeletons that represent a new pipine taxon, Singidella latecostata gen. et sp. nov.

• Read more about A new pipine frog from an Eocene crater lake in north-central Tanzania

A new species of chimaeroid, Ischyodus rayhaasi sp. nov., is described based primarily upon the number and configuration of tritors on palatine and mandibular tooth plates. This new species is named in honour of Mr Raymond Haas. Fossils of I. rayhaasi have been recovered from the Upper Maastrichtian Fox Hills Formation and the Breien Member and an unnamed member of the Hell Creek Formation at sites in south-central North Dakota and north-central South Dakota, USA.

• Read more about A new species of Ischyodus (Chondrichthyes: Holocephali: Callorhynchidae) from Upper Maastrichtian shallow marine facies of the Fox Hills and Hell Creek formations, Williston Basin, North Dakota, USA

Micrhystridium-like acritarchs are widely distributed in basal Cambrian cherts and phosphorites in South China. This paper describes similar acritarchs from the basal Cambrian Yurtus and Xishanblaq formations in Tarim, north-west China. The taxonomy of these acritarchs is revised. The basal Cambrian acritarch assemblage in Tarim and South China is characterized by three genera: Asteridium Moczydlowska, Heliosphaeridium Moczydlowska and Comasphaeridium Staplin, Jansonius and Pocock. This assemblage is named the Asteridium-Heliosphaeridium-Comasphaeridium (AHC) acritarch assemblage.

• Read more about Basal Cambrian microfossils from the Yurtus and Xishanblaq formations (Tarim, north-west China): systematic revision and biostratigraphic correlation of Micrhystridium-like acritarchs

A new metazoan, Skeemella clavula gen. et sp. nov., is described from the Middle Cambrian Pierson Cove Formation of the Drum Mountains, Utah, USA. Skeemella is similar to vetulicolians, but differs from other examples of this group in the relative proportions of the anterior and posterior sections, the large number of divisions, and the elongate bifid termination. The posterior section is arthropodan in character. The similarity of this fossil to vetulicolians throws hypotheses of their deuterostome affinity into question and highlights their problematic status.

• Read more about A new metazoan from the Middle Cambrian of Utah and the nature of the Vetulicolia

A new skull belonging to the species Eurhinodelphis cocheteuxi (Cetacea, Odontoceti, Eurhinodelphinidae), found in the upper Lower-Middle Miocene of Antwerp (Belgium, southern margin of the North Sea Basin) associated with its ear bones (periotic, tympanic bullae, malleus and incus), is the basis of a redescription and systematic revision of the species. This species is then used as an isolated taxon in a phylogenetic study of extinct and extant odontocetes. The main results of the cladistic analyses are: a sister-group relationship between E.

• Read more about Phylogenetic affinities of the long-snouted dolphin Eurhinodelphis (Cetacea, Odontoceti) from the Miocene of Antwerp, Belgium

Palaeozoic corals and stromatoporoids exhibit a variety of internal banding phenomena, many of which have been commonly interpreted as annual growth bands. We evaluate bands through analysis of colonial corals and stromatoporoids from three stratigraphic intervals: Upper Ordovician of Manitoba Canada, and Llandovery-Wenlock and Ludlow of Gotland, Sweden.

• Read more about Classification and controls of internal banding in Palaeozoic stromatoporoids and colonial corals

Vendoconularia triradiata Ivantsov and Fedonkin, recently described from Vendian (latest Proterozoic) strata of Russia, has been interpreted as a six-sided conulariid cnidarian. However, comparison of published illustrations of V. triradiata with Palaeozoic conulariids suggests that certain key features of the anatomy of V. triradiata should be reinterpreted. Specifically, features previously homologized with the corners of conulariid thecae may actually be homologous to the conulariid midlines.

• Read more about Reinterpretation of a conulariid-like fossil from the Vendian of Russia