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A new occurrence of the carbonaceous fossils Chuaria circularis and Tawuia dalensis is reported from subsurface Neoproterozoic in the Khastakh 930 Borehole in the Lena-Anabar Depression, northern Yakutia. Neoproterozoic deposits in this region are regarded as belonging largely to the Yudomian Stage. There have been no faunal records from this site and the strata directly underlying fossiliferous Permian deposits are, on lithostratigraphical grounds alone, regarded as Cambrian.

• Read more about Biostratigraphical implications of a Chuaria–Tawuia assemblage and associated acritarchs from the Neoproterozoic of Yakutia

A conulariid fauna from the Lower Visby Beds (uppermost Llandovery-lowermost Wenlock) is described, based on microscopic exoskeletal parts found in limestones and marls prepared using standard laboratory techniques for phosphatic fossils. Although not a single complete conulariid specimen has ever been found in the unit, conulariids were evidently abundant during the deposition of the Lower Visby Beds, as inferred from the microscopic fragments. So far, five species have been identified: Conularia sarae sp. nov., C. wimani sp. nov., C. sp. a, Metaconularia aspersa, and Pseudoconularia aff.

• Read more about Conulariid microfossils from the Silurian Lower Visby Beds of Gotland, Sweden

The hadrosaurid dinosaur Telmatosaurus transsylvanicus from the Late Cretaceous of the Hateg region of Romania is redescribed and its phylogenetic position among hadrosaurids and successive sister-taxa is evaluated. Hadrosauridae is defined and diagnosed as a monophyletic group on the basis of twelve of the best-known genera and species previously referred to this higher taxon. T. transsylvanicus lacks a number of features (among them, narrow mandibular condyle of the quadrate, narrow dentary teeth, single large carina on dentary teeth) that diagnose remaining members of Hadrosauridae.

• Read more about Telmatosaurus transsylvanicus from the Late Cretaceous of Romania: the most basal hadrosaurid dinosaur

Anatomically preserved one to five year-old stems are described from a Triassic site in the central Transantarctic Mountains. They are assigned to Kykloxylon fremouwensis gen. et sp. nov. and are regarded as related to the corystosperm stem Rhexoxylon on the basis of wood and pith anatomy and leaf trace organization. Kykloxylon axes possess a solid vascular cylinder of secondary xylem of the Dadoxylon type, but lack centripetal wood and a narrow pith. The bases of leaves attached to one-year-old stems of K.

• Read more about Petrified stems bearing Dicroidium leaves from the Triassic of Antarctica

A specimen of the Kimmeridgian pliosaur Pliosaurus brachyspondylus includes three elements which do not appear to be plesiosaurian. A pair of left and right dermal scutes are ascribed to an unidentified armoured thyreophoran ornithischian dinosaur, and a single fragment is less definitely ascribed to the same animal. It is presumed that the pliosaur had been scavenging a dinosaur corpse shortly before its own death, and that the scutes were transported inside the pliosaur's stomach.

• Read more about Remains of an ornithischian dinosaur in a pliosaur from the Kimmeridgian of England

Fossil hemiasterid echinoids of Hemiaster (Leymeriaster) are sexually dimorphic, females having wider gonopores than males. No other conspicuous morphological differences permit the two sexes to be distinguished, but in certain populations females achieve larger sizes than males and consequently seem hypermorphic.

• Read more about Sexual dimorphism in mid-Cretaceous hemiasterid echinoids

The Euthycarcinoidea is a superclass of the arthropod phylum Uniramia and one of the rarest groups of fossil arthropods. Only seven species in five genera have been described, from rocks of Late Carboniferous age in France and the USA, and of Middle Triassic age in France and eastern Australia. Here, a much older euthycarcinoid, from a mixed sequence of fluviatile and aeolian sandstones of probable Late Silurian age in Western Australia, is described as Kalbarria brimmellae gen. et sp. nov.

• Read more about A euthycarcinoid arthropod from the Silurian of Western Australia

A new large galeaspid, Bannhuanaspis vukhuci gen. et sp. nov., is described from the top part of the Si Ka Formation or the base of the Bac Bun Formation (Early Devonian, Late Lochkovian or Early Pragian) in the Phu Luong District, Bac Thai Province, northern Vietnam. The overall shape of its head shield is suggestive of the 'Polybranchiaspidiformes', but this morphology is regarded as a primitive feature for the Galeaspida.

• Read more about A new Early Devonian galeaspid from Bac Thai Province, Vietnam

Three large populations of graptoloids from the Middle Ordovician Utica Shale of Quebec contain Orthograptus quadrimucronatus micracanthus and Amplexograptus praetypicalis. Detailed orientation studies show that the two species reached the bedding plane at different times and were probably present in the water mass as monospecific shoals. Some size ranges of each population are orientated, suggesting that current sorting occurred. Few siculae are present, either because of current winnowing or because of geographical separation of growth stages in life.

• Read more about Population analysis and orientation studies of graptoloids from the Middle Ordovician Utica Shale, Quebec

Rhabdopleura obuti sp. nov. is described from the late Middle Cambrian Mayan Stage of the Sukhan Depression, Siberia, and is the second rhabdopleurid to be described from the Cambrian. It is probably one of the oldest' living fossils', remaining unchanged for over 520 Ma. This colonial pterobranch consists of stolonal and zooidal tubes. The creeping portion commonly found in most pterobranchs is reduced, with the colony adopting an erect growth habit. The stolonal tubes frequently show dichotomies and contain stolons. It is the earliest record of stolons.

• Read more about A new rhabdopleurid hemichordate from the Middle Cambrian of Siberia