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Background. The mostly Berriasian (Early Cretaceous) Purbeck Group of southern England has produced a rich turtle fauna dominated by the freshwater paracryptodires Pleurosternon bullockii and Dorsetochelys typocardium. Each of these species is known by numerous relatively complete shells and by a single cranium. The two other turtles found in the Purbeck Group (Hylaeochelys belli, a species of uncertain affinities, and the terrestrial helochelydrid "Helochelydra" anglica) are known only from shell remains. Methods. In the present contribution, we describe a new turtle cranium from the Purbeck Group of Swanage, Dorset (southern England). We also explore the phylogenetic relationships of this new cranium and of Hylaeochelys belli in the context of a recently published global turtle matrix. Results. Before complete preparation, the new Purbeck cranium was provisionally referred to Dorsetochelys typocardium, but our analysis clearly contradicts a referral to this species in particular and to paracryptodires in general. In contrast, the new cranium shares a number of features with the Late Jurassic, coastal marine Thalassochelydia, including a posterolaterally open foramen palatinum posterius, a strong ridge on the posterior surface of the processus articularis of the quadrate, a strong posterior orientation of the processus articularis in ventral view, and a processus trochlearis oticum limited to the medial part of the otic chamber and bordered by a deep recess laterally. Our phylogenetic analysis confirms a placement of the new Purbeck cranium within the clade Thalassochelydia. Discussion. In terms of morphology, the new Purbeck cranium does not correspond to any known taxon. However, we refrain from naming a new species based on it because there is a good chance that this cranium actually belongs to the shell-based species Hylaeochelys belli (also recovered as a thalassochelydian in our phylogenetic analysis). Unfortunately, we lack any objective evidence to support

In 1999 a Kimmeridgian age vertebra of a sauropod dinosaur was discovered directly in a layer of clays from Cricqueboeuf in Normandy, France. The vertebra is now located at the Paleospace museum and was part of an inventory in 2015 as well as the subject of this Master thesis. Two shells of the oyster Deltoideum delta typical of the upper Jurassic, sits on the vertebra making it easy to identify the original stratigraphic position of the vertebra. The origin of the vertebra, found in situ in a bed of clays, and the presence of these oysters assure that the vertebra belongs to the Kimmeridgian (between 157,3 ± 1 and 152,1 ± 0.9 millions of years). No reworking is possible in this environment of low energy and with a such weight (2,430 kg). The position of the vertebra in the skeleton of a sauropoda has been ascertained in this study. It belongs to the caudal part of the skeleton, but the position in the tail was more difficult to find. Fortunately, with some literary review, the vertebra is identified as a middle caudal vertebra essentially based on its dimension and based on the presence of the articulation facets for a typical bone in the tail, the chevron. The goal of this study was also to find a clade of dinosaur to which we can link this vertebra. Based on its morphology, the base of the neural arch is located on the anterior two thirds of the centrum; this is a particularity of the Titanosauriform dinosaurs. After reviewing the sauropod fauna present during the Kimmeridgian in Europe, the two titanosauriforms to which this vertebra can be referred are Europasaurus holgeri from Germany and Lusotitan atalaiensis from Portugal. Arguments are established to compare with these two taxa. Cricqueboeuf’s vertebra seems to have some morphological characteristics of Lusotitan atalaiensis. It should be considered that the comparisons could have been done with closest fauna like sauropods of England but unfortunately, they stay very poorly known. The paleogeography of the, Under andra världskriget förstördes många paleontologiska samlingar och mycket få lämningar av sauropoder, stora växtätande, fyrfota dinosaurier från juratiden (för ungefär 208 till 146 miljoner år sedan), har bevarats i Frankrike. Ett fynd från Normandie, Frankrike av en trolig fossil ryggradsdel, donerat till Paleospace museum av fru och herr Hurtrelle, verkar vara det enda exemplaret av en sauropod som finns bevarad i offentliga samlingar.Målet med denna studie är att uppskatta ålder på den fossila skelettdelen, bestämma dess position i dinosauriens kropp, undersöka vilken gren av familjen Dinosauria som den tillhör och slutligen försöka bestämma dess möjliga geografiska levnadsplats.Kotan är täckt av två typiska ostron, Deltoideum delta, från den övre juratiden. Tack vare detta var det lätt att bestämma dess ursprungliga stratigrafiska läge. Ostronen visar att fossilet tillhör Kimmeridgian (mellan 157,3 ± 1 och 152,1 ± 0,9 miljoner år). Denna studie visar att fossilet ursprungligen är en del av svansen av en sauropod. Dess exakta placering inom svansen var svårare att bestämma men jämförande litteraturstudier visar att kotan förmodligen tillhör mittregionen av svansen. Detta baseras i huvudsak på kotans dimensioner och förekomsten av specifika morfologiska element som är typiska för ben på svansens undersida. En ryggkota består av ett centrum, neuralbågen och de artikulära ytorna för chevronbenet. Baserat på dess morfologi ligger basen av neuralbågen på de främre två tredjedelarna av centrumdelen. Detta är en särprägel hos Titanosaurier. Granskning av den sauropoda faunan under Kimmeridgian i Europa visar att dessa karaktäristiska drag hos ryggkotan indikerar att den kommer från titanosauriformen Lusotitan atalaiensis från Portugal.Den paleogeografiska rekonstruktionen under Kimmeridgian visar att fyndplatsen låg under vatten och Frankrike bestod av ett fåtal öar. I dagsläget vet vi väldigt lite vad gäller fördelningen av fauna mellan dessa olika öar, mycket på

Background. The mostly Berriasian (Early Cretaceous) Purbeck Group of southern England has produced a rich turtle fauna dominated by the freshwater paracryptodires Pleurosternon bullockii and Dorsetochelys typocardium. Each of these species is known by numerous relatively complete shells and by a single cranium. The two other turtles found in the Purbeck Group (Hylaeochelys belli, a species of uncertain affinities, and the terrestrial helochelydrid "Helochelydra" anglica) are known only from shell remains. Methods. In the present contribution, we describe a new turtle cranium from the Purbeck Group of Swanage, Dorset (southern England). We also explore the phylogenetic relationships of this new cranium and of Hylaeochelys belli in the context of a recently published global turtle matrix. Results. Before complete preparation, the new Purbeck cranium was provisionally referred to Dorsetochelys typocardium, but our analysis clearly contradicts a referral to this species in particular and to paracryptodires in general. In contrast, the new cranium shares a number of features with the Late Jurassic, coastal marine Thalassochelydia, including a posterolaterally open foramen palatinum posterius, a strong ridge on the posterior surface of the processus articularis of the quadrate, a strong posterior orientation of the processus articularis in ventral view, and a processus trochlearis oticum limited to the medial part of the otic chamber and bordered by a deep recess laterally. Our phylogenetic analysis confirms a placement of the new Purbeck cranium within the clade Thalassochelydia. Discussion. In terms of morphology, the new Purbeck cranium does not correspond to any known taxon. However, we refrain from naming a new species based on it because there is a good chance that this cranium actually belongs to the shell-based species Hylaeochelys belli (also recovered as a thalassochelydian in our phylogenetic analysis). Unfortunately, we lack any objective evidence to support