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In Jurassic Phragmoteuthis huxleyi Donovan (Order Phragmoteuthida) the siphuncular wall shows unique structural and morphological features. The septal neck is short, about one-eighth of chamber length, but the connecting ring is extremely long, extending through 5-6 chambers. The permeable siphuncular wall in each chamber is, therefore, unusually thick and consists of 5-6 consecutive connecting rings.

• Read more about Siphuncular structure in some fossil coleoids and Recent Spirula

Phragmoteuthida from the Lower Jurassic (Upper Sinemurian) of Dorset, England, are fully described for the first time. Two species are recognized and described: Phragmoteuthis montefiorei (J. Buckman) and P. huxleyi sp. nov. Phragmocones have an apical angle of between 20 and 30 degrees, and relatively few chambers compared with belemnoids. The conotheca is multi-layered. The siphuncle is thick-walled. The pro-ostracum is long and three-lobed as in the Triassic species. Arms are short and bear pairs of slightly curved hooks.

• Read more about Phragmoteuthida (Cephalopoda: Coleoidea) from the Lower Jurassic of Dorset, England

Key aspects of the morphology, autecology, systematics and taphonomy of the crustacean syncarids from the Montceau Lagerstätte (Upper Carboniferous, Stephanian B; France) are presented. Palaeocaris secretanae is the most abundant faunal element of the Montceau biota and shows striking morphological similarities with Palaeocaris typus from the Mazon Creek Lagerstätte (Westphalian D; Illinois, USA).

• Read more about Syncarid crustaceans from the Montceau Lagerstätte (Upper Carboniferous; France)

Fossil eggshells from the Late Miocene Urumaco Formation of north-western Venezuela are reported. Stereomicroscopy and scanning electron microscopy were used to examine shell gross morphology and ultrastructure, respectively. Diagnostic turtle features in the eggshells include a distinct pattern of crystal aggregations within the shell units. The eggs had an elliptical shape with a maximum diameter of c. 56.5 mm and width of c. 43.5 mm, as measured in a specimen preserving the egg's outline.

• Read more about A nesting site and egg morphology of a Miocene turtle from Urumaco, Venezuela: evidence of marine adaptations in Pelomedusoides

Isolated material of 21 graptolite species from the upper Telychian of Latvia and Estonia is described. New thecal structures are recognized in Streptograptus, for example enrolment of the disto-lateral margin of the flange in distal S. nodifer thecae, possession of proximal lobes in S. wimani and elongated proximal lobes in S. sp. 3. S. spp. 1 and 2 both possess a nozzle, but do not have coiled metathecae. Thecal asymmetry in Oktavites falx is shown to be the reverse of that in O. spiralis. Several new Streptograptus and Monoclimacis species remain to be described.

• Read more about Isolated graptolites from the Telychian (Upper Llandovery, Silurian) of Latvia and Estonia

The first abundant, well-preserved fossils of the unusual archosauromorph reptile Trilophosaurus jacobsi Murry are from an Upper Triassic bonebed in the lowermost Trujillo Formation of the Chinle Group in Borden County, Texas. A nearly complete left side of the skull and incomplete but articulated mandible of a juvenile individual demonstrate that Trilophosaurus jacobsi Murry is referable to Trilophosaurus, so the putative procolophonid genus Chinleogomphius is a junior objective synonym of Trilophosaurus. Features of T. jacobsi that diagnose it from T.

• Read more about Revision of the archosauromorph reptile Trilophosaurus, with a description of the first skull of Trilophosaurus jacobsi, from the Upper Triassic Chinle Group, West Texas, USA

A new Pleistocene megatheriine, Megatherium celendinense sp. nov., is reported from a cave in the north of the Peruvian Andes.

• Read more about Megatherium celendinense sp. nov. from the Pleistocene of the Peruvian Andes and the phylogenetic relationships of megatheriines

Brachiopods from the late Ordovician (late Caradoc) Dulankara Formation of the Chu-Ili Range, Kazakhstan, are reviewed. Those from the upper two members of the formation, the Degeres and Akkol members, are systematically described. New genera from the Dulankara Formation are Nikitinamena (Plectambonitoidea: Leptellinidae), with type species Nikitinamena bicostata sp. nov., and Weberorthis (Orthoidea: Plectorthidae), with type species Mimella brevis Rukavishnikova.

• Read more about Late Ordovician brachiopods from the Dulankara Formation of the Chu-Ili Range, Kazakhstan: their systematics, palaeoecology and palaeobiogeography

Geometric morphometric analysis using relative warps is applied to the skull roof of 62 species of stereospondyls and their closest outgroups (i.e. basal archegosauriforms) from among temnospondyl amphibians. Twenty-one landmarks and five taxonomic groups are used for comparisons. Their skull evolution is quantified in a morphospace defined by two relative warps axes. The majority of groups show poor concordance between morphological and phylogenetic distances. The only exception is represented by Yates and Warren's study of stereospondyl relationships, in which concordance is high.

• Read more about Geometric morphometrics of the skull roof of stereospondyls (Amphibia: Temnospondyli)

A seed-bearing pinnate leaf found in the Chinle Formation of Late Triassic age in Arizona appears to be an archaic seed fern that more closely resembles typical Carboniferous-Permian seed fern leaves than any younger form. The fossil, which is described here as Chilbinia lichii gen. et sp. nov., incorporates characters of several Palaeozoic taxa.

• Read more about Chilbinia gen. nov., an archaic seed fern in the Late Triassic Chinle Formation of Arizona, USA