The Lower Ordovician (Tremadocian) linguliformean brachiopods of the southeastern part of the Anglo-Brabant Massif are documented systematically for the first time. The material belongs to a single Belgian locality (La Roche-en-Brabant), situated in one of the few valleys that incise the Mesozoic-Cenozoic cover, and more precisely from the topmost part of the siliciclastic Mousty Formation (Tangissart Member). Here, minute, poorly diverse linguliformeans are associated with planktic graptolites (Rhabdinopora) and nileid trilobites (Platypeltoides). They consist of three species belonging to three genera (Obolidae and Elkaniidae), of which only Broeggeria is known with certainty, due to the poor preservation of the material. In the Belgian part of the Stavelot-Venn Inlier, the presence of linguliformean brachiopods within the Floian Les Plattes Member of the Ottré Formation, which were reported more than 150 years ago, remains unconfirmed. The genus Broeggeria, known from several Belgian Tremadocian localities, is a relic from the Cambrian brachiopod fauna. By the Tremadocian it is well established globally between the Low-Latitude and High-Latitude provinces. The Belgian assemblage has strong similarities with assemblages from Baltica reflecting the early Palaeozoic changing palaeogeography.
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RBINS Staff Publications 2025
The lower Eocene (Ypresian) Cambay Formation at Vastan Lignite Mine in Gujarat, western India, has yielded a rich vertebrate assemblage including the earliest modern mammals and oldest birds of the Indian subcontinent. Among the herpetological faunas, snakes, lizards and amphibians are abundant, but, strangely, lizards are only represented by agamids. Here we describe the agamid assemblage based on numerous, diverse and well-preserved dentaries, premaxillaries, and maxillaries. At least four taxa are present at Vastan. Vastanagama susanae is characterized by dentaries with a large symphyseal facet, three anterior pleurodont teeth followed by acrodont teeth presenting a main cusp bordered by two lateral crests; the teeth increase in size posteriorly toward the coronoid process. Tinosaurus indicus exhibits a subdental ridge between the tooth row and the Meckelian canal, pleurodont symphyseal teeth including one that can be caniniform, and acrodont and tricuspid posterior teeth with poorly differentiated lateral cusps. Two other taxa represent two new genera and species. The first taxon presents multicuspid acrodont teeth with the main cusp surrounded by two or three progressively smaller lateral cusps. The second taxon presents pleurodont anterior teeth followed by a few acrodont teeth and ending with three or four subacrodont teeth near the coronoid process. Our results confirm that Agamidae (assigned to the Acrodonta) is the only lizard group present at Vastan, whereas many other groups are already present in the Early Eocene on the other continents. Agamidae is considered to have had a Gondwanan origin, with 52 genera and 420 species of extant agamids known from Asia, Australia, Africa and a few from Southern Europe. The oldest occurrence of formally recognized Acrodonta is found in the Jurassic of India. Other fossil agamids are known in the Upper Paleocene of Kazakhstan, Paleocene and Eocene of China, Early Eocene of Europe, Eocene of North America, and Middle Eocene of Pakistan. The diversity of the agamids in India and the absence of other lizard groups at Vastan tentatively support the Out-of-India hypothesis for agamids.
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