Tortoises (Testudinidae) are a clade of turtles highly specialized to terrestrial environments, mainly living in semi-arid conditions. Herein, we present Manouria morla sp. nov., a new species of the genus Manouria, which is considered to be the most basal extant testudinid genus. The studied material comes from the Ahníkov I fossil site, formerly known as Merkur or Merkur-North, located in the Most Basin in NW Bohemia (Czechia), dated to the Early Miocene (Burdigalian, MN 3). Manouria morla sp. nov. is the oldest member of the Manouria lineage, which nowadays inhabits SE Asia only, and therefore its biogeography and plausible European origin are discussed. The specific type of multiplication of plastral scutes in the inguinal region is discussed as a new morphological character diagnostic for the genus. Based on zoological studies, specific environmental requirements of the genus Manouria allow us to use this taxon as a proxy for the paleoclimate reconstruction of the Ahníkov I fossil site which suggests a broadleaf evergreen tropical wet forest. The simplified use of fossil testudinids as a proxy for reconstructing semi-arid palaeoclimate is therefore disproven.

The Late Miocene Gargano “Terre Rosse” in southern Italy has yielded a diverse vertebrate fauna that comprises an array of endemic taxa, including forms characterized by extreme sizes and unique morphologies. We here document new testudinid fossil remains from this insular assemblage. The material comprises a mandible, abundant (though mostly fragmentary) shell remains, appendicular elements, and a few vertebrae, originating from different localities within the Gargano assemblage. Based on its femur morphology, we tentatively refer the Gargano form to Solitudo, a late Neogene and Quaternary insular genus, otherwise known from a few Mediterranean islands. Unfortunately, the incomplete preservation of the trochanters hinders observation of the main diagnostic character of Solitudo, however, the similarities in the femoral head and diaphysis allow an open identification of the Gargano material as cf. Solitudo sp. Still, the Gargano tortoise offers new anatomical information on the Mediterranean insular tortoises. An interesting feature of the few preserved plastral elements is the presence of sulci as distinct raised ridges, a character that has been reported in other insular extant and extinct tortoises as well. The preserved hyoplastron has a medially straight and laterally concave humeropectoral sulcus and a wide axillary scute, pointing to some resemblance to geochelonans. Moreover, the morphology of the mandible from Gargano, which has its lingual serration reaching towards the symphyseal area, is also indicative of geochelonan affinities. If our identification is correct, the Gargano form would correspond to the earliest occurrence of Solitudo, denoting that this insular testudinid already radiated during the Late Miocene. A thorough overview of the diversity and taxonomy of insular testudinids from the Mediterranean islands is provided.

We reassess the taxonomy of the problematic taxon “Podocnemis” argentinensis from the Maíz Gordo Formation (late Paleocene) at Quebrada Queñoal (type locality), Departamento de Humahuaca, Jujuy province, Argentina. This plastron-based species was initially named as a member of the genus Podocnemis (Podocnemididae) based on the holotype and one referred specimen. Considering the dubious generic assignment of the holotype of “Podocnemis” argentinensis, we performed a thorough revision of the morphological characters of this taxon, based on the holotype and previously undescribed specimens from the same lithostratigraphic unit in the Casa Grande-Vizcarra river area (western flank of the Mal Paso Range, Tres Cruces Sub-basin) in Jujuy province, Argentina. The new referred specimens include a collection of shells found in association with one skull from Quebrada del Agujero, as well as some shells from Quebrada del Puesto in the same region. Comparison between the extended hypodigm of “Podocnemis” argentinensis and other podocnemidids suggests the assignment of this species to a new generic entity, based on the presence of a short preorbital skull portion with steeply curved prefrontal bones, both exoccipital bones with a dorso-medial process restricting the dorsal part of the foramen magnum to a narrow cleft, lateral orbits, absence of an interorbital groove, high maxillae, a large vomer and the generalized gular, extragular and humeral scute pattern. We included this species in a phylogenetic analysis to assess its relationships with other pelomedusoid turtles. It is recovered as the sister taxon of Gestemys powelli, with which it shares the following four synapomorphies: foramen posterius canalis carotici interni outside the basisphenoid, long basioccipital, reduced nuchal embayment and dorsoventral flattening of the shell. The clade including “Podocnemis” argentinensis and Gestemys constitutes a Paleogene Argentinean lineage which is more closely related to Erymnochelyinae and Peltocephalinae than to Podocnemidinae, a position supported by a more covered adductor fossa and a large anterior opening of the cavum pterygoidei.

Thalassochelydians represent one of the earliest radiations of coastal to marine-adapted turtles, spanning from the Jurassic to Cretaceous periods. This study describes Craspedochelys renzi sp. nov., a new thalassochelydian, “plesiochelyid” turtle from the Hauterivian stage of the Early Cretaceous in Colombia. It is the youngest and the only known record of “Plesiochelyidae’ outside Europe. The holotype, housed at the Naturhistorisches Museum Basel, was rediscovered after over 60 years and includes a partial shell, hindlimb bones, and caudal vertebrae. C. renzi shares key traits with “Plesiochelyidae”, including a V-shaped posterior plastral lobe lacking an anal notch; an indentation at the hypoplastra-xiphiplastra contact; an “intermediate” bone between neural 8 and suprapygal 1; a fully ossified carapace and bridge; and absence of carapacial fontanelles. Within “Plesiochelyidae”, it is assigned to Craspedochelys by its broader carapace, with an estimated length/width ratio of 4.12 for left costal 4, similar to other species in the genus; a relatively shorter plastron; and wider hyoplastra. Geological evidence links the specimen to the Moina Formation, a shallow marine deposit from the Hauterivian. This discovery expands the genus’ spatial and temporal range, underscoring its evolutionary and paleobiogeographic significance. It highlights the importance of museum collections in re-evaluating long-overlooked specimens, enriching our understanding of past biodiversity and turtle dispersal patterns.

The Division of Vertebrate Zoology at the American Museum of Natural History (AMNH) seeks an Assistant Curator in either the Department of Ornithology, Ichthyology, or Mammalogy to start on or after J...