Fossils of the endangered sturgeons and peddlefishes are widely distributed. We here report for the first time the presence of one of the extinct osteichthyes genus Cylindracanthus (Liedy 1856a) from the Early Eocene lignite-bearing successions of the Kutch Basin, India. The present well preserved rostrum is characterised by numerous wedge-shaped components encircling the central canal that runs along its length, paired at the base and each wedge contributing to the formation of a ridge. The rostrum lacks teeth. The present find extends the palaeobiogeographical distribution of Cylindracanthus considerably and supports its Eocene age as dental remnants preserved in Cylindracanthus sp. shows a decrease in remanent dentition and tooth bases from the Cretaceous to the Eocene. Cylindracanthus is an useful palaeoenvironmental indicator as it has been found associated typically with deposits of nearshore marine environments. 

Book of Abstracts of the XXII Annual Meeting of the European Association of Vertebrate Palaeontologists, 30 June–5 July 2025, Kraków, Poland. 

The Late Campanian Cerro del Pueblo Formation, located in southeastern Coahuila, Mexico, has produced a diverse array of vertebrate fossils. However, pterosaur remains from this unit are notably scarce. In this study, we describe new pterosaur material from the formation. The specimens include a fragmentary vertebra identified as belonging to an indeterminate, but derived pterodactyloid, along with the distal condyle of a left metacarpal, referable to an azhdarchoid pterosaur, and a left manus print. While these specimens provide additional evidence of pterosaur presence in the region during the Late Cretaceous, their fragmentary nature limits precise taxonomic and ichnotaxonomic identification. Nevertheless, they highlight the potential for future discoveries that could refine our understanding of the diversity and distribution of pterosaurs in Mexico.
  

Numerous “Quaternary” large-mammal fossils have been collected since the 1830s along the Le Riège stream, near Pézenas (Southern France). More than 120 specimens are stored in the collections of the Université de Montpellier (UM) under the name “Le Riège”. A major operation aiming at relocating the palaeontological collections of the University has made it possible to group together all the specimens of interest and launch their systematic revision for the first time. The fossils belong to the Reboul (1839; 51 samples) and de Christol (1865; 18 samples) Collections and 17 samples compose the Crochet & Ivorra Collection (1998). The remaining 38 samples have no mention about the exact time and location of their finding. We provide a critical inventory with literal transcription of inscriptions on specimens and historical labels. This revision confirms the presence of two distinct faunal assemblages under the name of “Le Riège”: Saint-Palais (Early Pliocene, MN14–15) and Le Riège sensu stricto (late Early Pleistocene, most likely MNQ19). The former assemblage, with coastal affinities, is composed of the ruminants Alephis sp. and Procapreolus cf. pyrenaicus, the rhinocerotid Pliorhinus megarhinus, the gomphotheriid Anancus arvernensis and marine mammals, all emblematic taxa for the Early Pliocene of Montpellier and Perpignan. The latter assemblage documents a late Early Pleistocene fluvio-volcanic sequence, yielding the bovid Bison (Eobison) spp., the cervid Eucladoceros cf. giulii, the hippopotamid Hippopotamus antiquus, the rhinocerotid Stephanorhinus etruscus, the equid Equus cf. altidens, and the elephantid Mammuthus cf. meridionalis, plus a few specimens of uncertain taxonomic affinities. This revision underscores the interest of revisiting historical collections and further provides a starting point for future research.
  

The locality of Dams (Quercy, southwestern France) has yielded two fossil assemblages, one from the late Eocene and another from the early Oligocene, making it one of the few localities with infillings across the Eocene-Oligocene transition. At least 24 taxa (13 mammals, 11 snakes) have been identified in this locality. Study of the lissamphibian remains from Dams yields an Eocene and an Oligocene assemblage, with a total of eight taxa. The Eocene assemblage includes two unnamed salamandrine species, one unnamed pelobatid species and one pyxicephalid species (Thaumastosaurus). The Oligocene assemblage includes two unnamed pleurodeline species, one salamandrine species (Salamandra sansaniensis) and an unnamed pelobatid species. Among the eight taxa from Dams, one Eocene salamandrine and one Oligocene pleurodeline are identified for the first time in the Quercy. A review of the lissamphibians from the Quercy area identifies eleven taxa for the Late Eocene (MP19) and eight taxa for Early Oligocene (MP22), with a major turnover at the Eocene-Oligocene transition. This turnover occurs in a time of major climatic changes, with a significant decrease in temperature and precipitation and concurrent increase in seasonality in Europe, likely affecting specialized taxa.
  

Herein we describe a small but relatively diverse assemblage of fossil fishes derived from the lower Oligocene (Rupelian) Red Bluff Clay at site AMo-9 in Monroe County, Alabama, USA. Identified amongst the remains are 15 unequivocal taxa representing 11 families within five orders, and one additional taxon represents an unknown order and family. Taxa identified include Eostegostoma sp., Otodus (Carcharocles) sp., Mitsukurinidae/Carchariidae indet., Macrorhizodus praecursor, Galeorhinus sp., Negaprion gilmorei, Physogaleus sp., “Sphyrna” sp., Galeocerdo sp., cf. “Aetobatus” sp., Sphyraena sp., Xiphiorhynchus kimblalocki, Xiphiorhynchus sp., Cylindracanthus ornatus, and C. rectus. Several additional fossils could not be identified beyond Lamniformes, Carcharhiniformes, and Teleostei, but they likely belong to one of the identified taxa within this paleofauna. All of the fishes previously reported from the Red Bluff Clay within the entirety of the Gulf Coastal Plain of the USA are otolith-based, and each of the 15 unequivocal taxa reported herein are important new records for this lithostratigraphic unit. In particular, the Eostegostoma sp. and Xiphiorhynchus spp. specimens represent the first occurrences of these taxa in Alabama. The specimens of C. ornatus, Eostegostoma sp., and X. kimblalocki are stratigraphic and temporal range extensions from the middle and late Eocene into the Rupelian Stage of the Oligocene. Other described taxa may represent transitional forms between those described from the late Eocene and late Oligocene within the region. This study provides a tantalizing preliminary view into faunal transitions that occurred amongst marine fishes across the Eocene/Oligocene boundary within the Gulf Coastal Plain of the USA. 

Two somewhat “odd” taxa of theridomyid rodents, one formerly known (Bernardia marandati Vianey-Liaud, 1991) and the other new (Idicia vidalenci gen. et sp. nov.) are discussed from a taxonomical and taphonomical perspectives. These two rodents were found at Lavergne, a late middle Eocene (MP16) “phosphatière” from the Quercy (Southwest France). The genus Bernardia, being preoccupied by a scale insect (Bernardia Ashmead, 1881), is here renamed Burgia. We benefit from this nomenclatural change to describe additional new dental specimens of this patriotheridomyine species, including a previously undescribed locus (P4). The other theridomyid from Lavergne, Idicia vidalenci gen. et sp. nov., so far documented by a mandible preserving two teeth (m2-m3) is a new taxon of peculiar occlusal morphology, and whose subfamilial affinities remain unknown. These two peculiar theridomyids recorded at Lavergne are found nowhere else, whether in coeval localities in Quercy or elsewhere in Western Europe. We discuss the possible causes of their unique presence at Lavergne.
  

A cheek tooth recently unearthed in the Lopar Sandstone unit, of late Eocene age, in the northern part of Rab Island, Croatia, is one of the very few Eocene mammalian remains found in the Adriatic area. Thorough comparison of this tooth with those of Old-World Palaeogene mammalian orders suggests that it is a M3 belonging to an embrithopod afrothere. The specimen is referred to as Palaeoamasia sp. This genus was formerly known only in Eocene deposits of Anatolia but with close relatives in Romania among Palaeoamasiinae. The geographical distribution of this subfamily perfectly matches the recently-named Balkanatolian landmass, which experienced in-situ evolution of endemic mammals prior to the Grande Coupure event that occurred around the Eocene–Oligocene transition. This last event is characterised by massive Asian immigration in Western Europe and the supposed extinction of many endemic Central and Western European mammals, including Palaeoamasiinae.
  

Sirenians are among the common marine fossil remains found in the Faluns deposits of western France. We describe new material of a Dugongidae sirenian from the middle Miocene Savignean facies of La Morfassière quarry (Indre-et-Loire, northwestern France) that includes a well preserved and almost complete skull associated with its mandible, several vertebrae and ribs. The cranial remains exhibit features that allow to attribute them to Metaxytherium medium, a species recorded from the middle and early late Miocene of European and Mediterranean coasts. The discovery of an associated skull and mandible of this species is unusual in this area and deserves to be reported, mostly because its preservation contributes to a better knowledge of the variable structure of its skull and teeth anatomy. For the first time the body size and weight of M. medium can be assessed through regression equations based on skull measurements. The particularly good condition of the material can be explained by the calm and deep marine environment in which it was deposited.
  

Résumé :
L’étude des rongeurs Theridomorpha permet de suivre le déroulement d’une radiation adaptative pendant toute sa durée (Eocène moyen-Oligocène terminal), sur un territoire restreint à l’extrémité ouest de l’Europe Occidentale. Dans ce papier, la phylogénie de ce groupe est établie à partir d’une analyse cladistique reposant sur l’examen de 315 caractères (310 dentaires). Le groupe d’intérêt comprend 110 des 132 espèces (24 genres) de Theridomyoidea et deux genres encore inclus jusqu’ici dans les Reithroparamyinae qui rejoignent les Theridomorpha. Les groupes externes comprennent des Glires basaux, Cocomys, Tanquammys et 16 Ischyromyiformes. Un cadre phylogénétique robuste est produit, qui permet de clarifier la systématique des Theridomorpha. La position des Remyoidea (nov. sup.fam.) au sein des Ischyromyiformes, extérieure aux Theridomorpha, est confortée. Les Protadelomys et Tardenomys sont à la base des Theridomyoidea, avant la séparation en deux clades correspondant aux familles Pseudosciuridae et Theridomyidae. Les sous-familles sont consolidées : Pseudosciurinae et Sciuroidinae pour les Pseudosciuridae ; Issiodoromyinae, Oltinomyinae, Columbomyinae, Theridomyinae, auxquelles s’ajoute au moins une nouvelle sous-famille (Patriotheridomyinae), pour les Theridomyidae. La topologie des chrono-espèces (sensu Simpson), traitées antérieurement comme lignées évolutives, apparaît dans la plupart des cas sous forme de clades successifs dans lesquels les espèces sont le plus souvent arrangées de manière pectinée, émergeant dans l’ordre stratigraphique. L’analyse des caractères aux principaux nœuds permet de consolider les caractères diagnostiques des taxons et les tendances évolutives, ainsi que de discuter des divers parallélismes et convergences dans l’évolution des structures et patrons dentaires (e.g., émail des incisives unisérié chez les Issiodoromyinae et les Patriotheridomyinae, ou pseudo-multisérié chez les Blainvillimys les plus hypsodontes, les Protechimys et Archaeomys ; patrons dentaires téniodontes ; allongement des dents déciduales chez les Patriotheridomyinae, Issiodoromyinae et Theridomyidae ; sélénodontie ou lophodontie). Les dynamiques évolutives traduites par les changements morphologiques sont mises en relation avec les variations environnementales. Enfin, les implications biochronologiques de l’évolution des Theridomyoidea sont discutées.
Abstract:
The adaptive radiation of the rodents Theridomorpha occurred during a limited time window (middle Eocene to late Oligocene), on an area restricted to Western Europe. In this paper, the phylogeny of this group is established via a cladistic assessment of 315 morphological characters (310 dental). The group of interest encompasses 110 upon 132 species (24 genera) of Theridomyoidea, and two genera formerly included within the Reithroparamyinae, and which are included here within the Theridomorpha. The outgroups include basal Glires, Cocomys, Tanquammys and 16 Ischyromyiformes. A robust phylogenetic frame is produced, which allows clarifying the systematics of the Theridomorpha. Within the Ischyromyiformes, the Remyoidea (nov. supfam.) are set apart from the Theridomorpha. Protadelomys and Tardenomys represent the earliest offshoots of the Theridomyoidea, before the dichotomy between Pseudosciuridae and Theridomyidae. It supports the former subfamilies Pseudosciurinae and Sciuroidinae within the Pseudosciuridae; and for the Theridomyidae: the Issiodoromyinae, Oltinomyinae, Columbomyinae, Theridomyinae, with at least one new subfamily (Patriotheridomyinae). The topologies of the chronospecies (sensu Simpson), formerly considered as evolutionary lineages, appear in most cases as successive clades, in which the species are generally pectinately arranged and emerging in the stratigraphic order. The analysis of characters supporting the main nodes allow consolidating the diagnosic characters of the taxa and their evolutionary trends, as well as discussing the various cases of parallelism and convergence in the evolution of structures and dental patterns (e.g., uniserial incisor enamel for Issiodoromyinae and Patriotheridomyinae, or pseudo-multiserial for the most hypsodont Blainvillimys, Protechimys and Archaeomys; taeniodont dental patterns; lengthening of deciduous premolars for Patriotheridomyinae, Issiodoromyinae and Theridomyidae; selenodonty or lophodonty).
Evolutionary dynamics are analysed with respect to environmental changes. Finally, biochronological implications of the evolution of Theridomyoidea are discussed.
  

Welcome to the 18th conference of the EAVP, the first online meeting of our association. The pandemic emergency made it impossible to organize the in-person meeting in Benevento as we all had hoped. However, we couldn’t miss another EAVP meeting. Therefore, this year we are meeting online, trying to make the experience the closest to the in-person meeting possible, in order to offer the delegates the opportunity to share knowledge, build new networks and reinforce the old ones. We have received 137 communications, with more than 150 delegates from 24 countries. All the abstracts have passed a peer review process and are part of this special volume of Palaeovertebrata, the official journal of the EAVP. This year we are also offering a variety of workshops, roundtables and symposia on different topics. These include the annual “Pride EAVP: An LGBTQ+ Roundtable” and “Women in Palaeontology Roundtable Discussion”, together with the workshops on “Gendered Perspective in Palaeontological Research: from Definition to Action”, “International Palaeontology Education: Virtual Teaching and Real-World Learning”, “Stepping out of Academia: Why, When and How?”, “Introduction to Hypothesis Testing in Statistics”, “The Early-Middle Pleistocene Transition: Marked Mammal Turnover and Ecosystem Dynamic” (included in the early event for the XXI INQUA Congress in Rome 2023, “A Mediterranean Perspective on Quaternary Sciences”). To conclude, we are hosting two symposia on “Palaeoart: Diversity on and behind the Canvas” and “3D fossils, Robotic and Experimental Palaeontology”. We wish you all a happy and productive meeting. And see you in Benevento next year! 

HGL50 is a latest Early-early Middle Eocene vertebrate-bearing locality located in Western Algeria. It has produced the richest and most diverse fauna of amphibians and squamate reptiles reported from the Palaeogene of Africa. Moreover, it is one of the rare faunas including amphibians and squamates known from the period of isolation of Africa. The assemblage comprises 17 to 20 taxa (one gymnophionan, one probable caudate, three to six anurans, seven ‘lizards’, and five snakes). Two new taxa were recovered: the anuran Rocekophryne ornata gen. et sp. nov. and the snake Afrotortrix draaensis gen. et sp. nov. The locality has also yielded the first confirmed anilioid snake, the first Palaeogene gymnophionan, and probably the first caudate from the Palaeogene (and possibly from the Tertiary) of Africa. The presence of a caudate at that time in Africa would be of particular interest; unfortunately, the available material does not permit a definitive identification. The fauna comprises Gondwanan and more specifically West Gondwanan vicariants, probably autochthonous groups and a Eurasian immigrant (assuming that the identification of the caudate is accurate). The fauna from HGL50 is clearly distinguished from the few other Eocene assemblages of Africa. However, if this results largely from differences in geological ages, geographic positions of the localities and mainly differences in environments took a part in the composition of the faunas. 

Investigations of the Clinchfield Formation (middle Eocene, upper Bartonian) exposed at the Hardie Mine (Wilkinson County, Georgia, USA), produced 4,768 actinopterygian otoliths representing 14 taxa and increased the number of bony fishes threefold from the site. The somewhat limited richness was characterized by bonefishes, mud eels, conger eels, sea catfishes, cusk-eels, snooks, grunts, drums and croakers, and porgies. The assemblage had a relatively even distribution with Ophidiidae, Congridae, and Sciaenidae most common. Included in the otolith taxa was a new sciaenid genus and species, Eosciaena ebersolei, with unknown relationships to other Sciaenidae. The Clinchfield otoliths were compared to other middle and late Eocene in age otolith assemblages in Alabama, Mississippi, and Louisiana utilizing percentage similarity measurements. Analysis indicated that the Clinchfield otoliths were not greatly similar or greatly unlike the Moodys Branch and Yazoo Clay otolith assemblages. However, the Clinchfield showed little relationship to the slightly older Lisbon Formation in adjacent Alabama and is postulated to be related to global climatic and plate tectonic events. Biostratigraphically, the Clinchfield otolith taxa are essentially the same as the other formations except for the Lisbon, which has at least ten unique species. Abundances of Clinchfield otolith taxa indicate a possible sub-bioprovince in the eastern Gulf Coastal Plain. The Clinchfield otoliths indicate a tropical to perhaps subtropical, soft substrate, mainly normal marine to slightly reduced salinities, inner shelf (0–20 m) paleoenvironment with indications of proximal continental coastlines. This investigation represents an initial step in addressing the immensely understudied Paleogene otolith assemblages in Georgia.
  

We report the first confirmed fossil bats from North Dakota, including a new species referable to the Vespertilionidae represented by a maxilla with P4-M3 from the Brule Formation, Fitterer Ranch local fauna, early Oligocene, Whitneyan North American Land Mammal Age. Unassociated postcranial fragments of the humerus and femur also represent a vespertilionoid, but appear to reflect a different, unidentified species. The new taxon, Quinetia frigidaria sp. nov., is referred to the genus Quinetia, previously known only from approximately contemporaneous deposits in Europe. The new species is larger than Quinetia misonnei from the early Oligocene of Belgium. It is similar in some morphological characters to Chadronycteris rabenae (Chiroptera incertae sedis) of the late Eocene (Chadronian) of northwestern Nebraska and to Stehlinia species (?Palaeochiropterygidae) from the Eocene and Oligocene of Europe, but differs from each in morphological details of the dentition and maxilla. An unassociated talonid of a lower molar from Fitterer Ranch shows myotodont morphology, unlike the nyctalodont lower molars in Q. misonnei, and thus represents a second chiropteran taxon in the fauna. Quinetia frigidaria is a member of a Paleogene radiation of bats near the low point of the Eocene-early Oligocene decline in global temperatures, increased seasonal aridity, and loss of tropical floras from mid-latitude North America. 

The Las Águilas site near Porvenir de Jalpa, Coahuila, Mexico, is extremely rich in tetrapod remains comprising both bones and trackways of several dinosaur taxa of late Campanian age. Within a 50 m thick section we identified at least nine layers with dinosaur bone assemblages. In one of these the dinosaur bones are associated with remnants of eusuchian crocodilians, turtles, plesiosaurs, pterosaurs, tyrannosaurids, dromaeosaurids, parksosaurid, hadrosaurids, ceratopsids, and ankylosaurs. This layer is also rich in coprolites of turtles, crocodilians and likely theropods, thus providing evidence for the wealth of Late Cretaceous vertebrate life in the area. 

This paper describes the first hexanchid tooth from the Tithonian (Late Jurassic) of New Zealand. For the moment, this tooth represents the earliest representative of the fossil genus Notidanodon in the world and one of the most ancient neoselachians in the Southern Hemisphere. Despite the perfect state of preservation of the unique tooth, the species is left in open nomenclature, pending the discovery of additional specimens. Few nominal species have been assigned to the genus Notidanodon. Four from Cretaceous deposits: N. antarcti Grande & Chatterjee, 1987, Notidanodon dentatus (Woodward, 1886), Notidanodon lanceolatus (Woodward, 1886), Notidanodon pectinatus (Agassiz, 1843) and only two from Paleocene: Notidanodon brotzeni Siverson, 1995, and Notidanodon loozi (Vincent, 1876). Considering the important morphological variations observed between some of these species, it seems obvious that the genus Notidanodon is not monophyletic and will need a revision in the future. 
  

The stapes is the last of the middle ear ossicle chain and the smallest bone of the mammalian skeleton. Because it rests on the membrane of the fenestra vestibuli during life, the stapes may often fall within the bony labyrinth cavity when soft structures decay after death. In this work, we highlight the unexpected role that the bony labyrinth plays in the preservation of the stapes. Systematic investigation of the bony labyrinth of 50 petrosal bones of extinct and extant artiodactyls led to the discovery of eight cases of “intralabyrinthine” stapes. Three dimensional reconstructions of these stapes allow documenting stapes morphology of four extinct artiodactyl taxa: Microstonyx erymanthius (Suidae), Elomeryx borbonicus (Hippopotamoidea), ?Helohyus plicodon (Helohyidae), and an undetermined Cainotheriidae; and four extant ones Choeropsis and Hippopotamus (Hippopotamidae), and Tayassu and Phacochoerus (Suoidea). ?Helohyus plicodon from the Middle Eocene documents the oldest stapes known for the order Artiodactyla. Morphological study and metric analyses of our sample of artiodactylan stapes show that stapes are likely to carry relevant phylogenetic characters/signal within artiodactyls, and a potential Euungulata signature. 

Micro-CT imaging is an increasingly popular method in paleontology giving access to internal structures with a high resolution and without destroying precious specimens. However, its potential for the study of hypoplasia defects has only recently been investigated. Here, we propose a preliminary study to test whether hypoplastic defects can be detected with micro-CT (μCT) scan and we assess the costs and benefits of using this method instead of naked eye. To do so, we studied 13 fossil rhinocerotid teeth bearing hypoplasia from Béon 1 (late early Miocene, Southwestern France) as positive control and 11 teeth of the amynodontid Cadurcotherium (Oligocene, Phosphorites du Quercy, Southwestern France), for which enamel was partly or totally obscured by cement. We showed that all macroscopically-spotted defects were retrieved on 3D reconstructions and selected virtual slices. We also detected additional defects using μCT scan compared to naked eye identification. The number of defects detected using μCT was greater in the Cadurcotherium dataset (paired-sample Wilcoxon test, p-value = 0.02724) but not for our control sample (paired-sample Wilcoxon test, p-value = 0.1171). Moreover, it allowed for measuring width and depth of the defects on virtual slices (sometimes linked to stress duration and severity, respectively), which we could not do macroscopically. As μCT imaging is both expensive and time consuming while not drastically improving the results, we recommend a moderate and thoughtful use of this method for hypoplasia investigations, restricted for instance to teeth for which enamel surface is obscured (presence of cement, uncomplete preparation, or unerupted germs). 

The study of endocasts, or casts of the endocranial space, have played an important role in shaping understanding of mammalian, and particularly primate, brain evolution. Recently, the reconstructions of three-dimensional virtual endocasts from high-resolution computed tomography images have allowed for the visualization and quantification of endocasts in several Paleocene and Eocene primate species. Here we present the virtual endocast of MaPhQ 289 (informally known as the Montauban 9 skull), a specimen of Necrolemur antiquus Filhol 1873, a middle to late Eocene European primate of the family Microchoeridae. The virtual endocast of MaPhQ 289 reveals a lissencephalic surface morphology with expanded temporal poles and minimal overlap of the cerebellum or olfactory bulb by the cerebrum, which closely resembles the morphology of the endocast of its contemporary relative, Microchoerus erinaceus (Primates, Microchoeridae). MaPhQ 289 yields an endocranial volume (ECV) of 2.36 cm3, about 60% smaller than the volume of the most commonly cited ECV of N. antiquus. Thus, the size of the brain of N. antiquus relative to its body size is likely to be smaller than has been reported in previous literature, highlighting the importance of corroborating older ECV estimates with new evidence using 3-D imaging techniques. 

Bats are among the most numerous and widespread mammals today, but their fossil record is comparatively meagre and their early evolution poorly understood. Here we describe a new fossil bat from dental remains recovered from late Early Eocene sediments at Prémontré, northern France. This 50 million-year-old bat exhibits a mosaic of plesiomorphic and apomorphic dental features, including the presence of three lower premolars, a single-rooted p3, short p4 with metaconid, myotodont lower molars and a tall coronoid process of the dentary. This combination of features suggests it is an early member of Vespertilionidae, today’s most speciose and geographically widespread bat family. The Prémontré bat has bearing on hypotheses about the origins of vesper or evening bats (Family Vespertilionidae), as well as crown-group chiropterans.