The zombie worm genus Osedax Rouse et al. 2004 is part of a peculiar group of organisms that thrive at whale fall localities on the ocean floor. In addition to feeding on whale bones, extant Osedax spp. are known to feed on the bones of other marine and terrestrial mammals, birds, and reptiles, and have recently been found to also feed on shark tooth dentine under experimental conditions. The efficacy of Osedax spp. as bioeroders is such that they are thought to have significantly affected both the quantity and the quality of the marine vertebrate fossil record. Here, we report on the occurrence of single-entry borings consistent with those produced by Osedax on fossil shark teeth from the Lower Pliocene offshore deposits of Tuscany, central Italy. Micro-CT investigations reveal that the worms excavated the dentine of the tooth roots, leaving the enameloid-coated crowns seemingly unaltered. The borings in question are assigned to the Osedax -related ichnogenus Osspecus Higgs et al., 2012, which to date had been found on a variety of marine vertebrate fossils, but not on shark teeth. This ichnological record provides the first fossil evidence for zombie worms exploiting shark tooth dentine and serves as a powerful demonstration that such behaviour can and does occur in the wild. Root exploitation by Osedax may contribute to explain the high frequency of rootless teeth in some shark tooth accumulations from modern deep-sea floors and time-averaged horizons inland. Over the past 100 million years, shark teeth have likely served as critical ecological stepping stones between remote marine vertebrate fall localities and may even have provided a suitable substrate for ancient zombie worms during the Cretaceous–Paleogene (K–Pg) extinction event.

Members of the Aspidorhynchidae, an extinct family of ray-finned fish (Actinopterygii) are amongst the most common larger predatory fish in the Late-Jurassic Solnhofen Archipelago. Aspidorhynchids from these localities have yielded specimens with prey fish stuck in their mouths and stomachs. We report here on isolated skulls and, in one case, a body fragment of Aspidorhynchus with attached gastrointestinal tract, whereas all other parts of the body of these specimens are missing. These extraordinary fossils are probably feeding-remains left over by larger predators, apparently unique in the fossil record and even for the Solnhofen Archipelago something special that is hardly known. As proof that these diffuse appendices to the cranium are gastrointestinal tracts, we show here for the first time prey fish and, in one case, a crustacean visible in some of these gastrointestinal tracts.

A new crocodylomorph fossil specimen (ML2631) from the Upper Jurassic of Lourinhã (Portugal) is described, based on a partially preserved skull table and braincase. The specimen was recovered from the Zimbral vertebrate microfossil assemblage, located in the lower part of the Praia Azul Member of the Lourinhã Formation (Kimmeridgian–Tithonian transition). The fossil was scanned using high-resolution micro-computed tomography (µCT), enabling the digital reconstruction of internal cranial structures, such as the brain cavity, cranial nerves, inner ear and paratympanic sinus system. These reconstructions represent the first neuroanatomical data ever reported for Atoposauridae, a clade of small-bodied neosuchian crocodylomorphs common in the Late Jurassic and Cretaceous of Europe. Phylogenetic analysis places ML2631 within Atoposauridae and contributes to resolving previously uncertain relationships within the group. Although fragmentary, ML2631 exhibits a unique combination of anatomical features, including a dorsolaterally open cranioquadrate passage, a sagittal crest along the frontal and parietal, a large, posteriorly placed and septate choana, large supratemporal fenestrae with a distinct posterior fossa and a squamosal lobe bearing a discontinuous lateral groove. These traits, amongst others, distinguish ML2631 from all other known atoposaurid species. Additionally, its neuroanatomical proportions suggest a dwarf adult individual with low-frequency auditory sensitivity and moderate visual acuity, consistent with a primarily terrestrial or nearshore lifestyle, coherent with the depositional environment of the fossil site. Taken together, these results highlight the taxonomic and evolutionary relevance of the specimen and underline the importance of future discoveries of more complete material to confirm its systematic and phylogenetic status within Atoposauridae.

Alligatoroidea is the crocodylian superfamily that includes extant alligators, caimans and many related extinct taxa. Palaeogene North America offers a rich record of alligatoroid diversity representing more than a dozen forms. The Eocene-aged Hancock Mammal Quarry (HMQ, Clarno Formation, John Day Fossil Beds National Monument, central Oregon, USA) has yielded two crocodylian fossils, a right humerus and the anterior portion of a left lower jaw from an unknown alligatoroid. Though fragmentary, discrete morphological traits of the HMQ alligatoroid are shared with several contemporaneous alligatoroids, but the suite of character states is unique. Though its phylogenetic placement is uncertain, the presence of an alligatoroid in north-western North America, along with the biostratigraphic record of other Palaeogene alligatoroids and Asian floral and faunal associations of the HMQ suggest that an Asian origin for the taxon is plausible.

Herpetofauna, particularly amphibians and reptiles, exhibit high levels of endemism and distinct diversity pattern on Taiwan island. However, the biogeographic history of these groups remains obscure, in part due to the lack of a herpetofaunal fossil record. Here, we report the first fossil record of frogs and snakes from Taiwan, based on Middle Pleistocene vertebrate assemblage recovered from the Chochen–Tsailiao area in southern Taiwan. The collection includes a vertebra of a bufonid frog and multiple vertebrae of colubrid and viperid snakes. Despite their fragmentary preservation, several vertebrae are identifiable, including a toad (Duttaphrynus melanostictus), rat snakes (Ptyas mucosa and P. cf. mucosa), a wolf snake (Lycodon rufozonatum), and a pit viper (Protobothrops sp.). Additional vertebrae are attributed to Colubridae indet. and Alethinophidia indet. The preservation of these delicate skeletal elements in a tectonically active and humid subtropical setting highlights the exceptional nature of this discovery. Palaeoenvironmental reconstruction based on ecological preferences of extant analogues suggests that the region supported a humid fluvial and open woodland environment with abundant water bodies.

Chyzeriidae Womersley, 1954, is a family of trombidiform mites characterized by unique body structures and habits, though it has not been well studied. A new genus and species, Cretachyzeria macrosetagen. et sp. nov., in the subfamily Pteridopinae of Chyzeriidae, found in Cretaceous amber in Myanmar, provides the first formally described fossil species in this family. A phylogenetic study of Chyzeriidae based on postlarval morphology supported the morphological classification. The dorsal setae of Cretachyzeria macrosetagen. et sp. nov. are extremely long and dense, resembling the quills of a porcupine. This unusual morphological structure likely served specific biological functions. We hypothesize that these long setae functioned as a specialized defense, protecting the fragile abdomen and aiding in predator deterrence in its complex environment. Given the geological time frame of this fossil mite and the wide distribution of extant Chyzeriidae, we propose that the family existed prior to the breakup of Pangaea.

Hypsodontinae is a highly specialized subfamily of Bovidae, primarily distributed across East and West Asia as well as Eastern Europe during the Miocene; however, the type genus Hypsodontus had not been documented in East Asia. Here, we report a new species of Hypsodontus, Hypsodontus sinensissp. nov., from the Dongxiang Formation at the Citan locality, Linxia Basin, China, dating to the late Early Miocene (~17.2 Ma). This marks the first definitive record of the type genus in China. The new material consists of a horn core that exhibits more than 1/3 circle of strong homonymous twisting, uniform elongation, and a smooth surface, displaying closer affinities to H. pronaticornis. The age of Hypsodontus sinensissp. nov. represents the oldest known record, suggesting that this genus might have originated in China and radiated during the late Early Miocene or early Middle Miocene. The evolutionary relationships among the members of Hypsodontinae, i.e., Hypsodontus, Kubanotragus, and Turcocerus, are also discussed here. Materials from the Xishuigou locality and the Halamagai Formation of the Junggar Basin may represent an ancestral form of these genera mentioned above, possibly an early variant of Kubanotragus. The discovery of this new species at the Citan locality illustrates an early diversification of Hypsodontus in China and provides critical insights into the early evolution of Bovidae.

Gryllidea, one of the most species-rich groups in Orthoptera, are characterized by relatively scarce fossil records until the K-Pg extinction. This study describes a unique Mesozoic cricket, Fortigryllus xiangruigen. et sp. nov., based on a well-preserved specimen from mid-Cretaceous Kachin amber in northern Myanmar. It exhibits very peculiar morphologies including fore-, mid-, and hindlegs nearly equal in robustness, and exceptionally stout femora in all three pairs of legs. Although it has some putative synapomorphies with the Phalangopsidae, the lack of information on the genital characters forbid us to accurately attribute it to a precise family. Crawling is tentatively proposed as a mode of locomotion in this Mesozoic cricket. This new find reveals a novel morphology in Cretaceous crickets and suggests a great potential biodiversity of crickets in this mid-Cretaceous ecosystem.

The Campisano Ravine in the Ribesalbes-Alcora Basin (Spain, Early Miocene, Biozone C, MN 4) yielded a diverse and abundant assemblage of muroids, comprising five distinct taxa, and nearly 700 remains. The assemblage yielded five muroid taxa: Megacricetodon primitivus, Democricetodon decipiens, Eumyarion weinfurteri, Melissiodon sp., and Muroidea indet. The most abundant taxa were M. primitivus and D. decipiens, with M. primitivus being the most prevalent in the oldest sites and D. decipiens in the most recent ones. E. weinfurteri was exclusively identified in the FS1, MAB3, and MAB5 sites of the most recent biozone (L. ellipticus, see Crespo et al. 2021). In contrast, Melissiodon sp. was confined to the BC-1 and MAB-3 sites. M. primitivus was present in all Iberian basins, whereas D. decipiens exhibited considerable variability, being recorded in the Ca biozone of the Calatayud-Montalbán Basin, the last part of the C biozone of the Vallès-Penedès Basin, and the Buñol site. It can be hypothesised that the studied basin may be a factor in the distribution of this species across the regions in question. Eumyarion was present in the Vallès-Penedès Basin from the first part of the C biozone, subsequently migrating to the studied basin and appearing in the Cb biozone in the Calatayud-Montalbán and Buñol basins. Melissiodon was absent from the latter basin from the MN3 biozone to the last part of the C biozone and from the MN5 biozone in the Vallès-Penedès Basin. The presence of muroid faunas in the Early Miocene suggests that the coastal Ribesalbes-Alcora Basin functioned as a transitional region between the forested areas of west and central Europe and the drier inner Iberian Peninsula basins.

Probnis sauvanyaensissp. nov., the first representative of the ‘grylloblattodean’ family Probnidae from the Iberian Peninsula, is described from the middle to ?upper Permian outcrop of Sauvanyà in the Catalan Pyrenees. The family is otherwise represented by two additional species of Probnis from the ?middle Permian of the USA and by a single genus and species from the ?Lower Triassic of Ukraine. As is known from outcrops with rather extreme climates, the family may have survived the global warming of the Permian–Triassic crisis. We also describe a roachoid of the family Spiloblattidae from the same outcrop as the second representative of this family from the Iberian Peninsula.