Uma equipe internacional paleontólogos do Grupo de Biología Evolutiva da UNED, do Museu Nacional de História Natural e da Ciência, da Fundación de Historia Natural Félix de Azara (Universidad Maimónides), do CONICET e da Faculdade de Ciências da Universidade de Lisboa, apresentam no XII Congresso Nacional de Geologia, realizado no final de junho, em Évora, algumas mais recentes descobertas sobre os fósseis do Jurássico Superior de Pombal.
As jazidas fossilíferas de Andrés e Junqueira em Pombal, com cerca de 150 milhões de anos, têm revelado uma extraordinária diversidade de fósseis de dinossáurios e outros vertebrados, reforçando a importância de Pombal como uma das principais regiões portuguesas para o estudo do Jurássico Superior. Entre os resultados apresentados destaca-se o estudo de um pequeno réptil esfenodonte (grupo atualmente representado pela Tuatara) encontrado na jazida de Andrés (Santiago de Litém, Pombal). Neste trabalho intitulado “A new Opisthodontian sphenodontian from Pombal (Portugal) and its implications for Late Jurassic lepidosaur evolution”, e apresentado pelo paleontólogo Francisco Ortega, o excelente estado de conservação do fóssil permitiu melhorar o nosso conhecimento sobre a evolução destes animais no continente europeu durante Jurássico Superior. O resumo desta apresentação encontra-se abaixo:
Sphenodontians are relics today of a once diverse and globally distributed component of Mesozoic terrestrial ecosystems. Yet, their Upper Jurassic European record remains scarce and fragmentary outside classic localities such as Solnhofen (Germany) and Cerin (France). Here we report a new sphenodontian from the Tithonian of the Lusitanian Basin (Andrés site, Pombal, Portugal), representing one of the most complete specimens of a fully terrestrial sphenodontian from the European Upper Jurassic. The material reported in preliminary studies includes a partial skeleton preserving a complete skull and articulated postcrania. The specimen comes from fluvial to floodplain deposits of the Bombarral Fm., indicating a fully terrestrial environment linked to a low-energy meandering river system. Comparative anatomical analysis supports its assignment to Opisthodontia, showing close affinities with the North American species Opisthias rarus, particularly in mandibular structure and dentition. However, a unique combination of cranial and dental features justifies its recognition as a distinct taxon. Phylogenetic analyses based on recent datasets of eusphenodontians recover this taxon within a lineage of terrestrial opisthodontians distributed across Laurasia during the Late Jurassic. The presence in Portugal of a form close to Opisthias rarus supports hypotheses of episodic faunal connectivity between North America and southwestern Europe across the proto-North Atlantic during the Kimmeridgian–Tithonian interval, followed by regional differentiation. The exceptional preservation of this specimen not only provides new insights into the anatomy of early opisthodontians but also expands the known geographic range of this poorly represented group into the Iberian landmass and reinforces the Lusitanian Basin as a key region for understanding Late Jurassic vertebrate diversity and paleobiogeography. Moreover, this represents the first definitive record of sphenodontians in the Iberian landmass, together with forms from the UK, suggesting a previously underestimated diversity of terrestrial sphenodontians in Europe and expanding our understanding of their ecological and evolutionary roles.
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