The discovery of a new stem turtle from the Middle Jurassic (Bathonian) deposits of the Isle of Skye, Scotland, sheds fresh light on the early evolutionary history of Testudinata. 1995; Joyce 2009): (Past due Triassic, Argentina); (Late Triassic, USA); (Early Jurassic, South Africa); and (Early Jurassic, USA). Perhaps more importantly, these discoveries have prompted major reappraisals of basal turtle associations (Rougier 1995; Joyce TRV130 HCl 2007) that have challenged what may be termed the traditional interpretation of turtle phylogeny (e.g. Gaffney & Meylan 1988; Gaffney 1991, 2007; Gaffney 1996). According to the traditional model, the turtle stem group consists of only and (1995) and Joyce (2007) suggested the turtle stem group was significantly more diverse and that several varieties previously thought to be basal members of the crown group should be considered as stem taxa. Following from this fresh interpretation of basal turtle associations, the origin of the turtle crown group (Testudines Joyce 2004; see the electronic supplementary material for any definition of clade titles used in this paper) techniques from the Past due Triassic to no later on than Past due Jurassic (Joyce 2007). Some evidences, including reappraisal of fragmentary material from your Bathonian of England (Scheyer & Anquetin 2008), suggest that the crown group may have arisen in the Middle Jurassic. In this context, the Middle Jurassic represents a critical interval for understanding turtle development and the origin of the crown group; however, the fossil record for this period is definitely sparse and is made up mainly of poorly known Pancryptodiran (Joyce 2004) TRV130 HCl taxa (e.g. Nessov 1995; Tong 2005; Peng 2005; Scheyer & Anquetin 2008). However, two additional stem turtles from your Jurassic have TRV130 HCl been explained recently: (Sukhanov 2006; Middle Jurassic, Russia) and (Sterli 2008; Middle to Late Jurassic, Argentina). and are both known on the basis of partial cranial and postcranial remains from a small number of individuals. Here, we describe a new stem turtle from your Bathonian (Middle Jurassic) of the Isle of Skye, Scotland. This fresh taxon is known from at least six individuals and represents the most complete Middle Jurassic turtle explained to date. As a result, it provides useful fresh insights into the development and palaeoecology of stem Testudines. 2. Systematic palaeontology Testudinata Klein 1760 (Joyce 2004) gen. et sp. nov. (a) Etymology from your Scottish Gaelic term for island; from your Greek term for turtle; in honour of Dr Michael Waldman, co-discoverer of the Cladach a’Ghlinne locality (together with the late Prof. R. J. G. Savage) and the person responsible for introducing one of us (S.E.E.) to the site. (b) Holotype NMS G 2004.31.15 (National Museums of Scotland, Edinburgh), a partial skull (figure 1gen. et sp. nov. Stereophotographs of the skull NMS G TRV130 HCl 2004.31.15 (holotype) in (in the TRV130 HCl electronic supplementary material): (a) a partial shell (missing part of the left side of the plastron), with poorly preserved cervical vertebrae and a partial shoulder girdle; (b) a complete shell (carapace figured in number 2gen. et sp. nov. (sp., crocodilians, the lepidosauromorph sp., numerous squamates, pterosaurs, dinosaurs, the synapsid and early SCDGF-B mammals (Waldman & Savage 1972; Savage 1984; Evans & Milner 1994; Waldman & Evans 1994; Evans & Waldman 1996; Barrett 2006; Evans 2006). (e) Analysis Relatively small turtle (carapace length of approx. 250C300?mm) characterized by the following list of features: presence of nose; elongated postorbital skull; absence of flooring of the cavum acustico-jugulare; processus interfenestralis of the opisthotic more slender than that of more basal forms (e.g. can be explained. (a) Dermal roofer elements Nasals are present and contact one another along the midline for all of their size. The prefrontal has a reduced dorsal exposure and does not meet the additional prefrontal medially. The descending process of the prefrontal contacts the vomer ventrally, but it is definitely unclear whether or not it contacts the palatine. No evidence helps the presence of a lacrimal or lacrimal foramen in any specimen. The frontal forms part of the dorsal margin of the orbit avoiding contact between the prefrontal and postorbital. Internal parts of the parietal (representing the anterior extension of the braincase wall and processus substandard parietalis) are unfamiliar in all specimens. NMS G 2004.31.16f shows a posterolateral contact between the parietal and squamosal on the skull roof, which suggests the absence or weak development of an top temporal emargination. The jugal is definitely longer than high and forms a large part of the posteroventral margin of the orbit. There is no sign of a cheek (lower temporal) emargination. The quadratojugal has a long dorsal suture with the postorbital, preventing the jugal from achieving the squamosal. Posteriorly, the quadratojugal does not participate in the formation of the.