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Restudy of a hardground fauna from the Middle Jurassic of south-western Utah revealed the presence of thecideoid brachiopods. The absence of separated dorsal valves and the effects of abrasion and diagenesis hampered the description of the specimens. However, serial sectioning of complete shells revealed a thecidellinid which in its morphology and shell microstructure resembled Rioultina Pajaud from the Middle Jurassic of Europe. Important morphological differences clearly separate the new specimens from Rioultina and they are assigned to Stentorina sagittata gen. et sp. nov.

• Read more about The first thecideide brachiopod from the Jurassic of North America

Type specimens of Hyolithus tenuistriatus Linnarsson show this species to be the second definitive representative of the North American genus Nevadotheca in Scandinavia; H. subcostatus Wallerius is questionably assigned to that genus. Restudy of the types of the hyolithids Hyolithus pennatulus Holm confirms the earlier assignment of that species to Carinolithes Syssoiev and H. araneus Holm is assigned to Lovenedolithes gen. nov. Morphology of the orthothecids Hyolithus (Orthotheca) cor Holm, H. (O.) excavatus Holm and H.

• Read more about A revision of Holm's late Mid and Late Cambrian hyoliths of Sweden

Chemico-structures of shells representing all families presently assigned to the Linguloidea have undergone significant transformations since the Early Cambrian. Superficial hemispherical to hemi-ellipsoidal pits on the larval and/or mature shells are interpreted as casts of deformable, membrane-bound vesicles of mucus or rigid vesicles of glycoproteins or GAGs with thickened coats.

• Read more about Chemico-structural evolution of linguloid brachiopod shells

The first ichthyosaur to be recorded from the Pliensbachian Stage of the English Lower Liassic is described as Leptonectes moorei sp. nov., extending the geological range of Leptonectes to the Pliensbachian. According to criteria for assessing the maturity of ichthyosaurs, it is concluded that L. moorei is an immature individual of a relatively small, slender and short snouted species close to the earlier long-snouted L. tenuirostris (Conybeare) which ranges from the Rhaetian to the Sinemurian.

• Read more about A new Pliensbachian icthyosaur from Dorset, England

An intensive study of a collection of arthropods from the Cretaceous of Lebanon, formerly referred to as stomatopod larvae, reveals that these forms belong to the problematical arthropod class Thylacocephala. The species Protozoea hilgendorfi, P. damesi, and Pseuderichthus cretaceus display defining thylacocephalan characters such as a carapace enclosing the entire body bearing a large anterior optic notch; three pairs of large, raptorial appendages; and a posterior battery of small swimming limbs associated with muscle segments.

• Read more about Thylacocephala (Arthropoda: Crustacea?) from the Cretaceous of Lebanon and implications for thylacocephalan systematics

The new species Peltopleurus nuptialis is described on the basis of several well preserved specimens from the uppermost Ladinian Kalkschieferzone of Ca' del Frate. This new species is characterized by small size and the presence of hook-like fulcra on all fins except the caudal, and by tubercles on the rostral and nasal bones interpreted as secondary sexual traits. There is also a modified anal fin in supposed males, which probably acted as a gonopodium, pointing to a strong sexual dimorphism.

• Read more about Sexual dimorphism in a new species of the actinopterygian Peltopleurus from the Triassic of northern Italy

We examine the preservation, autecology and morphological variation for several characters of the Cretaceous gonorynchiform fish Dastilbe from the Lower Cretaceous of Brazil and Africa. More than 83 specimens were examined. We test species validity using characters of the caudal endoskeleton and meristic counts of fin-rays vs length. Evidence provided by fossilized soft tissues and slabs containing large individuals 'freeze framed' in the process of swallowing smaller prey meals, show that Dastilbe was predatory, at least as adults, as well as cannibalistic.

• Read more about The gonorynchiform fish Dastilbe from the Lower Cretaceous of Brazil

Conodonts, thelodonts and acanthodians have previously been collected from the Pridoli of Shropshire (Welsh Borderland) from bone beds such as the Ludlow Bone Bed. In general, specimens collected from these types of deposit are very abraded and make taxonomic studies difficult. This contribution describes well preserved thelodont microelements from two samples from the Downton Castle Sandstone Formation (Pridoli, Silurian) of the Much Wenlock area of Shropshire.

• Read more about A conodont, thelodont and acanthodian fauna from the lower Prídolí (Silurian) of the Much Wenlock area, Shropshire

A brief review of the unusual morphology and ontogeny of the ascoceratid shell is followed by revised description of the meagre British Silurian material assigned already to Ascoceras barrandei Salter and A. vermiforme Blake.

• Read more about The nautiloid cephalopod order Asococerida in the British Silurian

A new family of dragonflies, Palaeomacromiidae, based on Palaeomacromia multicellulata gen. et sp. nov., is described from the Late Paleocene Maiz Gordo Formation of north-western Argentina. The present discovery demonstrates that the present knowledge of the Early Cenozoic insect fauna of the Neotropical region remains very poor.

• Read more about A new libelluloid family from the Upper Paleocene of Argentina