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A numerical cladistic analysis of the conodont family Palmatolepidae has been undertaken to determine the applicability of the technique to group-wide systematic revision. Results suggest a new hypothesis of relationships that is considerably more parsimonious than trees compatible with existing hypotheses of relationships, or trees that are even loosely constrained stratigraphically.

• Read more about Conodonts meet cladistics: recovering relationships and assessing the completeness of the conodont fossil record

A new jawless vertebrate, Cornovichthys blaauweni gen. et sp. nov., is described from a single complete specimen from the Achanarras fish bed at Achanarras Quarry in Caithness, northern Scotland. The Achanarras fish bed consists of lacustrine laminites and was deposited in a major deep-water phase of the Orcadian lake during the deposition of the cyclic Caithness Flagstone Group. The Achanarras fish bed is of Middle Devonian (Eifelian) age. The new animal compares closely with Euphanerops, one ofthe Frasnian 'anaspids' (Hyperoartii) of the Escuminac Formation at Miguasha, Quebec, Canada.

• Read more about A new jawless vertebrate from the Middle Devonian of Scotland

Two samples of ammonoids belonging to the Oppeliidae, Sublunuloceras virguloidesHecticoceras (Brightii) canaliculatum, are analyzed to estimate the intraspecific variability of embryonic shell features. The study of embryonic shell characters reveals two main shapes of protoconch, flattened and round. Prosiphons may be straight or slightly curved. New parameters for area are added to the linear parameters commonly found in the literature. Prosiphon length and caecum area vary greatly whereas protoconch and ammonitella diameter vary only slightly, and the ammonitella angle is almost constant.

• Read more about Embryonic ammonoid shell features: intraspecific variation revisited

Skeletal encrusters and carbonate hardgrounds are rare in siliciclastic sands and gravels because of high levels of abrasion and sediment movement. An exception to this is the Maastrichtian Qahlah Formation of the Oman Mountains, a sequence of coarse siliciclastic sediments deposited on a shallow marine shelf above wavebase and at an equatorial palaeolatitude. This unit contains intercalated carbonate hardgrounds and other hard substrates which were encrusted and bored.

• Read more about Palaeoecology of hard substrate faunas from the Cretaceous Qahlah Formation of the Oman Mountains

Four fragmentary mandibles from the Stonesfield Slate facies, Taynton Limestone Formation, Middle Bathonian (Middle Jurassic), England, represent two species of AmphitheriumA. prevostiiA. rixoni sp. nov. Both species had five lower premolariform teeth. The composite formula for the lower dentition of Amphitherium appears to have been I/4, C/1, P/5, M/6-7. The seventh molar is not present in the presumably oldest individual, and its presence is regarded as probably an individual variation.

• Read more about Dental morphology of the Jurassic holotherian mammal Amphitherium, with a discussion of the evolution of mammalian post-canine dental formulae

Scanning electron microscopy of polished, slightly etched rock surfaces of samples from the Silurian of Gotland, Sweden, revealed the presence of excellently preserved calcareous microfaunas and microfloras. This paper illustrates several morphotypes of calcareous micro-organisms of unknown biological affinity, attributed to the new family Ovummuridae.

• Read more about A new family of calcareous microfossils from the Silurian of Gotland, Sweden

A review of evidence for parasitism on graptoloid graptolites is presented. The phenomenon is rare, having been recorded in only a few biserial forms and straight monograptids. Most periderm outgrowths secreted as a response to parasitism are small and blister-like, but in two new specimens remarkable tubular outgrowths occur. These would have had a detrimental, but clearly not fatal, influence on the functioning of these graptolites, particularly with regard to the hydrodynamics and buoyancy of the rhabdosorne and the energy expended in secreting additional periderm.

• Read more about Parasitism on graptoloid graptolites

A brief outline is presented of the geological conditions prevailing in the hard-water lake that produced the Las Hoyas fossiliferous site in the Serrania de Cuenca (north-east central Spain). The corresponding Barremian laminated limestones contain varied fossil remains including plants. The fern component of the assemblage is described in the present paper. Ten taxa are referable to the families Matoniaceae. Dicksoniaceae and Schizaeaceae, whilst eight are unclassified. A new species of Dicksoniaceae is described: Coniopteris laciniata.

• Read more about Early Cretaceous ferns from lacustrine limestone at Las Hoyas, Cuenca Province, Spain

The Late Tortonian-Early Messinian Abad Member in the Sorbas Basin, south-east Spain contains abundant foraminifera. Planktonic foraminifera have been used to reconstruct the environmental conditions that developed within the basin. Benthonic foraminifera reveal a detailed picture of the palaeoenvironment. After an initial deepening episode, from upper epibathyal (c. 200 m) depths to lower epibathyal (c. 1000 m) depths, the basin progressively shallowed to shelf depths (c.

• Read more about The Late Tortonian–Early Messinian foraminiferal record of the Abad Member (Turre Formation), Sorbas Basin, Almería, south-east Spain

Recent investigations of the Lower Devonian fauna of North Viet Nam have provided abundant invertebrates, among which chonetoidean brachiopods are especially common. Their good preservation has allowed the revision of eight of the nine species described in the literature. The North Vietnamese chonetoidean fauna is mainly characterized by the diversity of representatives of the Family Strophochonetidae (stropochonetines and parachonetines), which includes nine species.

• Read more about Lower Devonian chonetoidean brachiopods from Bac Bo, North Viêt Nam