La história de las colecciones de Paleontología del Museu Geológico (MG-LNEG) de Lisboa está relacionada con los primeros trabajos de cartografía geológica de Portugal e incluye algunas de las primeras especies de dinosaurios descritas en el registro portugués. Estas colecciones son particularmente significativas porque incluyen diversos ejemplares hallados en localidades (algunas actualmente inaccesibles) de la región norte del sector central de la Cuenca Lusitánica en la que el registro fósil está aún poco conocido. En las XXXVII Jornadas de la Sociedad Española de Paleontología, celebrada en Cuenca, de 5 a 8 de octubre 2022, se presentó un trabajo en el que se hace una revisión de los fósiles asignados a Megalosaurus depositados en las colecciones del MG-LNEG. La revisión de estos materiales ha permitido identificar ejemplares que se pueden asignar a distintos grupos de dinosaurios, incluyendo ornitisquios (estegosaurios y ornitópodos), saurópodos (incluyendo diplodocinos) y terópodos (Torvosaurus, Allosaurus y otros tetanuros indeterminados), además de algunos restos de crocodilomorfos. El resumen del trabajo es el siguiente:
The Museu Geológico (MG-LNEG) of Lisbon houses an important collection of fossils that gave rise to the first palaeontological works on Portuguese Mesozoic vertebrates, including some of the first dinosaur species described in Portugal. This collection is particularly significant because it supported some of the earliest works of geological cartography of the country and includes several specimens collected in localities (some of them currently inaccessible) from the northern region of the central sector of the Lusitanian Basin (e.g., Ourém, Porto de Mós and Leiria), which fossil record is poorly known. Theropod remains are relatively scarce in the collection and generally composed by fragmentary materials, most of them assigned to the “wastebasket” taxon Megalosaurus. At that time, this was a poorly understood taxon that included materials from the Middle Jurassic of England but also other elements from distinct ages and belonging to different vertebrate groups. The fossils attributed to Megalosaurus in the MG-LNEG mostly consist of isolated tooth and vertebrae collected from different localities of the Lusitanian Basin, spanning from the Oxfordian–Kimmeridgian to the Tithonian in age. Most of these specimens were firstly assigned to Megalosaurus insignis, a species named based on a tooth from the Upper Jurassic of Normandy, or to the Portuguese species Megalosaurus pombali, described based on some isolated teeth from Upper Jurassic localities at Pombal and Lourinhã. However, both species are currently considered as nomen dubium and the original materials can only be determined as Theropoda indet. A review of the MG-LNEG Megalosaurus materials allowed to identify remains of crocodylifoms; stegosaurian and ornithopod ornithischians; sauropods (including diplodocines); and Torvosaurus, Allosaurus, and other indeterminate tetanuran theropods.
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