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Histological study of new specimens of sinacanth fin spines from the Lower Silurian of the northwestern margin of the Tarim Basin (Xinjiang, China) shows that they have the same histology as the fin spines of chondrichthyans. On this basis it is argued that sinacanths are one of the oldest known chondrichthyans, rather than acanthodians, and their spines are the oldest known shark fin spines. Previous studies on sinacanths are critically reviewed. The family Sinacanthidae is erected to include Sinacanthus and its relatives with more than 15 fin spine ridges per side.

• Read more about Early Silurian sinacanths (Chondrichthyes) from China

Several dental remains of a new suid, Siamochoerus banmarkensis gen. et sp. nov., have been collected in the Late Eocene Krabi basin in southern Thailand. This species is morphologically close to but more primitive than Dubiotherium waterhousi (formerly Palaeochoerus waterhousi), and represents one of the oldest known suids. The date of origination of suids can therefore be placed back to the Late Eocene or even earlier, and the early evolution and diversification of the family might have occurred largely in the Oligocene of Asia.

• Read more about The earliest known pig from the Upper Eocene of Thailand

Build-ups of the calcareous tube, Tymbochoos (gen. nov.) sinclairi (Okulitch), occur in mid Ordovician limestones of the Ottawa Valley; the oldest previously known build-ups of calcareous tubes are Devonian. The Tymbochoos build-ups occurred as elongate dune-shaped structures in tidal channels on intertidal flats, and as small isolated pillow-shaped structures on near-shore subtidal shoals. Clustered tubes radiated horizontally from small attachment areas and then grew vertically.

• Read more about Morphology and palaeoecology of a primitive mound-forming tubicolous polychaete from the Ordovician of the Ottawa Valley, Canada

The Grivetian Dipleura dekayi Zone of the Bolivian Altiplano, and adjacent stratigraphical levels, yield representatives of the phyllocarid genera Echinocaris and Dithyrocaris. The peculiar morphology and well-preserved original features of the exoskeleton allow erection of a new species, Echinocaris spiniger sp. nov. Discovery of a carapace with abdominal somites still connected allows identification of the corresponding tail piece and description of the complete exoskeleton of Dithyrocaris oculeus sp. nov., probably one of the earliest representatives of the genus.

• Read more about Mid Devonian phyllocarid Crustacea from Bolivia

Conodonts are generally found as disarticulated skeletal elements, yet almost all aspects of conodont research rely on knowledge of the original arrangement of these elements in the apparatus. Analysis of rare, articulated 'natural assemblages' of taxa assigned to the order Ozarkodinida reveals that there was no significant variation in the skeletal architecture within this major group of extinct agnathans.

• Read more about Skeletal architecture, homologies and taphonomy of ozarkodinid conodonts

The dryolestoid mammal Dorsetodon haysomi gen. et sp. nov. is described from the Purbeck Limestone Group (Lower Cretaceous) of southern England, on the basis of lower molars. Dorsetodon is assigned to the Paurodontidae, a family of Theria previously known only from North America. The distinction between Paurodontidae and Henkelotheriidae (from the Upper Jurassic of Portugal), although maintained for lack of solid contrary data, is argued to have been based on variable or subjective characters. A further small mammal, Chunnelodon alopekodes gen. et sp.

• Read more about New dryolestoid mammals from the basal Cretaceous Purbeck Limestone Group of southern England

The dinoflagellate family Areoligeraceae, now extinct, was prominent from the Late Jurassic through to the Paleogene. Some areoligeracean species extend into the Neogene but, until now, no genus was known to originate in that interval. Thus, Ramidinium gen. nov., represented by Ramidinium tridens sp. nov. from the Lower to Middle Miocene of the Jeanne d'Arc Basin, offshore eastern Canada, becomes the last known areoligeracean genus to have appeared.

• Read more about A new areoligeracean dinoflagellate from the Miocene of offshore eastern Canada and its evolutionary implications

• Read more about Brachidia of Late Ordovician and Silurian eospiriferines (Brachiopoda) and the origin of the spiriferides: errata

A rare but widespread neuropterid of Westphalian D and Stephanian age, Neuropteris obtusa (Brongniart) comb, nov., is redescribed from specimens from north-west Spain and Saarland, Germany. Its synonymy includes Neuropteris raymondii Zeiller, 'Mixoneura' subraymondii Wagner, 'Callipteris' discreta Weiss, and Neuropteris thompsoniana Darrah. Pustules in the interveinal areas of the pinnules in some specimens are interpreted as the probable result of fungal attack by rusts, although that they are glands cannot be excluded.

• Read more about Neuropteris obtusa, a rare but widespread Late Carboniferous pteridosperm

Diverse brachiopod faunas are recorded and partly described from the Korotkinskaya Formation of the central Taimyr Peninsula, northern Siberia, Russia. The lowest fauna (Beds 2 and 3) includes eight species of indeterminate late Ordovician age, the main fauna (Bed 4) consists of 39 species of mid Ashgill age, and the highest fauna (Beds 8 and 9), four species of late mid Ashgill age. The new species Amphiplecia bondarevi, Cyclospira orbus, Eospirigerina vetusta and Plectatrypa laticostata are described.

• Read more about Late Ordovician brachiopods from Taimyr, Arctic Russia, and their palaeogeographical significance