We document a new species of ovulate cone (Pararaucaria collinsonae) on the basis of silicified fossils from the Late Jurassic Purbeck Limestone Group of southern England (Tithonian Stage: ca. 145 million years). Our description principally relies on the anatomy of the ovuliferous scales, revealed through X-ray synchrotron microtomography (SRXMT) performed at the Diamond Light Source (UK). This study represents the first application of SRXMT to macro-scale silicified plant fossils, and demonstrates the significant advantages of this approach, which can resolve cellular structure over lab-based X-ray computed microtomography (XMT). The method enabled us to characterize tissues and precisely demarcate their boundaries, elucidating organ shape, and thus allowing an accurate assessment of affinities. The cones are broadly spherical (ca. 1.3 cm diameter), and are structured around a central axis with helically arranged bract/scale complexes, each of which bares a single ovule. A three-lobed ovuliferous scale and ovules enclosed within pocket-forming tissue, demonstrate an affinity with Cheirolepidiaceae. Details of vascular sclerenchyma bundles, integument structure, and the number and attachment of the ovules indicate greatest similarity to P. patagonica and P. carrii. This fossil develops our understanding of the dominant tree element of the Purbeck Fossil Forest, providing the first evidence for ovulate cheirolepidiaceous cones in Europe. Alongside recent discoveries in North America, this significantly extends the known palaeogeographic range of Pararaucaria, supporting a mid-palaeolatitudinal distribution in both Gondwana and Laurasia during the Late Jurassic. Palaeoclimatic interpretations derived from contemporaneous floras, climate sensitive sediments, and general circulation climate models indicate that Pararaucaria was a constituent of low diversity floras in semi-arid Mediterranean-type environments.

No abstract

This study focuses on new records of freshwater bivalves from the Late Jurassic Vega, Tereñes and Lastres formations of Asturias, northern Spain. Five new taxa Mujanaia abeuensis gen. et sp. nov., 'Unio' asturianus sp. nov., Margaritifera? lagriega sp. nov., Asturianaia colunghensis gen. et sp. nov. and Asturianaia lastrensis gen. et sp. nov. are described and included in the families Unionidae and Margaritiferidae (Unionida); they are compared and contrasted with other European, Asiatic and North American species. Their discov-ery constitutes the oldest records of Unionida in Spain, and they provide new palaeogeographical data on the distribution and origin of this group in Europe. These taxa are also an effective tool for the environmental reconstruction of the Jurassic ecosystems of Spain's Dinosaur Coast.

No abstract

Three freshwater bivalve taxa are described from the Villar del Arzobispo Formation (Late Jurassic-Early Cretaceous) of Riodeva, Teruel, Spain. The stratigraphic range of the large and geographically widely distributed bivalve Margaritifera, previously recorded from the Early Cretaceous of Spain and southern England, is recognised to extend back probably into the Late Jurassic. This new record extends the palaeogeographic and temporal distribution of the family Margaritiferidae in Europe.