Comparison of shared morphological characteristics between living and extinct species is essential to reconstructing repeated phenotypic evolution in deep time. For example, the extinct Triassic-Jurassic redfieldiid ray-finned fishes possess tubercles on their snout which resemble the enlarged dermal odontodes that give some extant ray-finned fishes "bristly" snouts. The three-dimensional anatomy of redfieldiid snout tubercle-bearing bones is typically obscured in fossils, leaving the anatomical identity and homology of these snout tubercles uncertain. We describe new aspects of redfieldiid snout tubercles based on a recently collected, exceptionally well-preserved specimen (VMNH 129827) of †Redfieldius gracilis from lacustrine deposits of the Early Jurassic (Hettangian, ~201 million years old) Waterfall Formation of the Culpeper Basin (Newark Supergroup) of Virginia. We determine that the body and skull of †Redfieldius is covered with dermal odontodes, which are extended into bristle-like tubercles on the snout and orbit. The phylogenetic position of †Redfieldius outside of the teleostean total group indicates that redfieldiid snout tubercles evolved convergently from those in living fishes, such as the bristlenose catfish (Ancistrus) and the denticle herring (Denticeps). †Redfieldius does not have strong morphological overlap with extant snout tubercle-bearing ray-finned fishes, limiting inference of their ecological function. However, we posit that the snout tubercles of †Redfieldius, in concert with a covering of pointed dermal odontodes on the scales, may have served a defensive function. The enlarged snout tubercles in †Redfieldius are part of an emerging pattern of increasingly specialized tooth morphology in Late Triassic-Early Jurassic ray-finned fishes that mirrors living ray-finned fishes.

The modiolus is a complex anatomical region where multiple facial muscles converge to coordinate movements of the lips, cheeks, and oral fissure. Although its functional importance is well recognized, its intricate anatomy has been difficult to clarify using conventional methods alone. Six formalin-fixed human cadavers (nine hemifacial regions) without deformities were examined. Dissections were performed under 2.6× loupe magnification from the deep periosteal side to preserve the spatial relationships of the facial muscles forming the modiolus. Based on these findings, one well-preserved specimen was selected for detailed three-dimensional (3D) reconstruction. A tissue block containing the upper central modiolus was serially sectioned at 5μm thickness, stained with hematoxylin and eosin, digitally scanned, and reconstructed using 3D volume-rendering software, enabling selective visualization of individual muscles and their interrelationships. Loupe magnification dissection consistently identified the orbicularis oris, buccinator, zygomaticus major, levator anguli oris, and depressor anguli oris as core components of the modiolus. The orbicularis oris displayed a consistent three-layered structure; however, its detailed internal connections with other muscles could not be clearly identified at the muscle fiber level while preserving tissue relationships. Three-dimensional reconstruction demonstrated that muscle bundles of the labial part of the orbicularis oris and the zygomaticus major crossed obliquely and interwove tightly within the modiolus. Although in this study limited to a single specimen, this combined approach provides valuable insight into minute and intricate structures such as the modiolus, which is difficult to elucidate using conventional techniques alone.

ABSTRACT Antarctaspids, a basal subgroup within the Arthrodira, display a mosaic of arthrodire and petalichthyid features. However, their morphology has remained poorly understood due to the paucity of well-preserved specimens. Here, we describe a new antarctaspid arthrodire, Panjiangosteus eurycephala gen. et sp. nov., from the Posongchong Formation (Pragian, Lower Devonian) of Wenshan Prefecture, Yunnan, China. Using X-ray computed tomography, we reveal previously undocumented anatomical details of antarctaspids, including the neck joint and the dorsal surface of the neurocranium. In addition to diagnostic antarctaspid characters, Panjiangosteus also exhibits some features characteristic of more derived arthrodires, notably the convergence of middle and posterior pit-lines onto the central plate and the subdivision of the posterior pit-line into two discrete segments. Crucially, Panjiangosteus is characterized by its broad skull roof and the vertical sliding neck joints reminiscent of petalichthyids. Phylogenetic analysis recovered antarctaspids as a paraphyletic grade at the base of Arthrodira, with Panjiangosteus placed more derived than the other antarctaspids. These findings refine our knowledge of antarctaspid cranial morphology, shed new light on character transitions in early arthrodire evolution, and support a close relationship between petalichthyids and arthrodires.https://zoobank.org/urn:lsid:zoobank.org:pub:F07656F3-1537-48DD-8133-D67B44B9FE31

Syspastoxyelidae is an extinct basal hymenopteran lineage currently known only from mid-Cretaceous Burmese amber. Here, we describe a new genus and species, Cilioxyela setosa gen. et sp. nov., based on a well-preserved female specimen from the Hukawng Valley, northern Myanmar. The new taxon is assigned to Syspastoxyelidae based on diagnostic characters, including strongly proximally condensed forewing venation, a composite first flagellomere formed by fused ancestral segments, tibiae bearing dense robust spines, and segmented cerci. Cilioxyela gen. nov. differs from all previously described genera by a unique character combination, most notably, a distal forewing veinless membrane lacking longitudinal corrugation and conspicuously elongated marginal setae, together with a narrowed forewing, elongate pterostigma and anal cell, and distinctive antennal segmentation. These features support the establishment of a new genus. Comparative analysis indicates that distal forewing morphology in Syspastoxyelidae is more variable than previously recognized. The presence or absence of longitudinal corrugation in the distal forewing membrane likely reflects genus-level differentiation rather than a stable family-level synapomorphy. The new genus also supports a tentative division of Syspastoxyelidae into at least two morphologically cohesive groups, pending testing through additional fossil discoveries and quantitative phylogenetic analyses. The discovery of Cilioxyela setosa expands the known morphological disparity of Syspastoxyelidae and highlights evolutionary plasticity in distal forewing architecture among early Hymenoptera, contributing to a better understanding of morphological diversification in mid-Cretaceous forest ecosystems.

Mosquitoes are major vectors of human and animal diseases, making their accurate identification essential for vector surveillance and control. However, morphological identification has often been challenging, requiring taxonomic expertise and well-preserved specimens. Molecular markers, particularly DNA barcoding, offer an effective alternative for identifying both adult and immature stages. Ecuador is one of the most biodiverse countries in the world, a diversity that is also evident in its Culicidae fauna. This study provides a comprehensive revision of Ecuadorian mosquitoes, updating the national checklist and emphasizing species of public health importance. For species identification, an integrative approach was used combining morphology and DNA barcoding (COI and ITS2 regions). We list 266 species in 22 genera, of which 17 species are new national records, and 33 species are validated through molecular analysis. The updated checklist highlights Ecuador’s Culicidae diversity across its biogeographic regions, which represent 7% of the world’s mosquito diversity. These findings provide a critical foundation for future entomological research and vector control in the country.

The first genus and species of Eumastacoidea from the Lower Cretaceous Crato Formation of northeastern Brazil is described. Cratomastax mariellaae gen. et sp. nov . is reported from a relatively well-preserved specimen, with the wings, head, and metathoracic leg aspects in good condition. It is assigned to the Eumastacoidea based on its forewing venation feature, with M and CuA + CuPaα fused. Due to the presence of two branches of M + CuA, it may be allied to Chorotypidae, but the forewing venation of other families of Eumastacoidea is not sufficiently known to confidently exclude it from these taxa. Additionally, a second species of Aestuacrida is described from the Crato Formation. Aestuacrida mikronaulion sp. nov . is significantly larger than A. stereofemoris Schall, Lima, Heads, Pinheiro, Kotthoff & Husemann, 2025, and its wing venation is more fully preserved. The new species suggests that Aestuacrida belongs to the subfamily Pseudoacridinae, increasing the diversity of this recently established taxon. Lastly, a new specimen of Locustrix gallegoi Martins-Neto, 2003, is reported. Individuals of this genus appear to be rather rare, and the apomorphies of Locustrix Martins-Neto, 2003, were not well understood. The new specimen helps resolve this issue. Locustrix can now be assigned to the subfamily Locustopsinae. The genus is characterized by having two branches of M and CuA + CuPaα and a short ScP of only about 50% of the total forewing length.

EMILIN family extracellular glycoproteins in the basilar membrane (BM) have so far only been identified in the mouse. It may influence the stiffness and extracellular filamentous architecture essential for cochlear frequency tuning (Russell etal., 2020, Science Advances, 6, eaba2634). In our study, we explored whether elastic components, such as EMILIN-2 (elastin microfiber interface-located protein 2) and elastin, are also present in the human BM. In addition, we analyzed the fine morphology of the BM and tympanic covering layer (TCL) at different frequency locations using light, transmission electron, and scanning electron microscopy (LM, TEM, and SEM) in well-preserved human cochlear specimens. Tonotopic estimations were made from model extrapolations using synchrotron radiation phase-contrast imaging (SR-PCI) and 3D reconstruction of matched cochleae with delineated octave bands constructed using Greenwood's formula (Greenwood, 1961, Journal of the Acoustical Society of America, 33, 1344). Our immunohistochemistry and gene RNA sequencing (RNA-seq) data support that EMILIN-2 and elastin are expressed in the human BM. Expression pattern of both proteins that influence BM architecture vary along the frequency range. TEM analysis suggests that TCL cells are actively involved in the deposition of the amorphous substance and fibrillary network, conceivably serving to assemble extracellular and elastic constituents along the BM. Thus, our findings suggest that TCL cells may play an important functional role in human cochlear tuning, particularly at low frequencies potentially linked to our remarkable speech and music perception.

Visualizing archaeobotanical data: A comprehensive photographic record of desiccated plant remains from an early modern context at Santi Quattro Coronati, Rome.

Recent collecting of the Király Hill at Veszprémfajsz yielded a well-preserved Longobardian (upper Ladinian) fossil as­semblage from the red nodular limestone of the Buchenstein Formation in the northeastern part of the Balaton High­land. At the previously unknown fossil site about 230 well-preserved ammonite specimens were collected and 33 taxa were identified. Besides the well-known upper Ladinian genera (Megaphyllites, Epigymnites, Proarcestes, Monophyl­lites), several Arpadites and Protrachyceras species appeared in large numbers. The presence of Argolites species is also characteristic, although this genus is barely found at the nearby Katrabóca II site. We recognized and described three new genera (Pinterites, Paranolcites, Katrabocaites), one of which, the Katrabocaites, contains new species, as well. These new data significantly expand our knowledge on the upper Ladinian ammonites of the Mediterranean region. The taxo­nom­ic studies of the ammonite assemblage and its comparison with faunas of Alpine and Dinaric sites provides a more detailed picture of the relationship between the different habitats of the western Neotethys as well as an opportunity to refine the biostratigraphic division of the Ladinian stage.

The present investigation provides a detailed account of the gross morphology and topographical arrangement of a single late-gestation German Shepherd fetus, recovered following natural death associated with an obstetrical complication. Although most prenatal anatomical studies in dogs emphasize larger sample sizes to generate quantitative data, the meticulous examination of a single, well-preserved specimen offers unique value by enabling highly precise documentation of structural development. This individualized approach facilitates a fine-grained description of external landmarks, proportional body configuration, organ position, and the overall maturation status of major systems during advanced gestational age. Standardized gross dissection techniques were employed to examine external and internal features systematically, and the observations were interpreted in light of existing literature on canine embryology and fetal morphology. The fetus exhibited distinct craniofacial outlines, including a proportionately developed skull, clearly formed eyelids, and well-defined oral and nasal regions. Limb development was complete, with identifiable digital pads, flexion points, and joint demarcation indicating advanced musculoskeletal maturation. Internally, all visceral organs were appropriately enclosed within the thoracic and abdominal cavities, showing expected spatial organization for the gestational stage. The lungs displayed clear lobation patterns, while the heart, liver, kidneys, gastrointestinal tract, and urogenital structures appeared anatomically consistent with established prenatal developmental milestones. The relative positioning of the digestive, respiratory, circulatory, and urinary systems reflected near-term topographical organization, supporting the advanced developmental status of the fetus. This descriptive study, although based on a single specimen, contributes valuable baseline information relevant to veterinary anatomists, obstetricians, clinicians, and comparative morphologists. It also provides a useful reference for interpreting prenatal developmental variations, assessing congenital anomalies, guiding imaging-based fetal evaluation, and enriching anatomical teaching resources. The findings reaffirm the importance of detailed qualitative descriptions in complementing quantitative morphometric research on canine prenatal development.

Exceptionally well-preserved asteroid specimens from the Cenomanian and Turonian coastal exposures in Seine-Maritime (north-west France) are described. These include a new genus, Crielaster (type species: C. annae sp. nov.), provisionally assigned to the family Chaetasteridae, a new species of the astropectinid genus Coulonia (C. fournoui sp. nov.), and a new species of stauranderasterid (Stauranderaster pustulosus sp. nov.). A superbly preserved specimen of Oreaster coronatus Forbes, 1848, showing the construction of the abactinal surface, supports subdivision of the genus Stauranderaster. Stauranderaster coronatus is designated as the type species of Coronataster gen. nov., and Squamataster gen. nov. is erected with Oreaster squamatus Forbes, 1848 as its type species.

Abstract Plagiosaurids form a small but highly disparate clade of Triassic temnospondyls that are characterized by extremely flattened and wide skulls, large orbits and a knobby to pustular ornamentation. The largest European taxon is Plagiosternum granulosum from the Middle Triassic of Germany. Originally known from fragmentary bonebed material only, recent finds add well-preserved specimens that reveal the structure of the skull, mandible and pectoral girdle in great detail. The humerus and atlas of P. granulosum are described for the first time, and a putative cleithrum is identified. Ontogenetic changes include a proportional extension of the orbit, a more convex occipital margin, elongation of the parietal, proportional increase of the occipital condyles and formation of pustular ornament at nodal points of reticulate ridges. The presence of gastral scales can be inferred from the structure of the interclavicle, but there is no evidence of osteoderms. Plagiosternum granulosum was the most salt-tolerant temnospondyl in the Ladinian palaeoenvironments, where it dwelled brackish lagoons and lakes and formed a community with nothosaurids and other euhaline taxa.

Saucrosmylidae as an enigmatic Mesozoic lineage of Neuroptera, is characterized by its large body, typically expanded RA area, dense crossvenation and diversified wing patterns. A new species of Saucrosmylidae, namely Huiyingosmylus wangi sp. nov. is described based on a well-preserved specimen. This specimen bears four stretched wings and a partial body, including a significantly shortened foreleg, and was collected from the Middle Jurassic of Daohugou, Inner Mongolia, China. This new species further enhances the species diversity of Saucromylidae and also provides new information on the biological characteristics of this family.

Anakitium storozhenkoi Arakelyan & Yan, gen. et sp. nov. of the family Asiocoleidae (Coleoptera: Archostemata) was discovered in the Tunguska coal basin at the Anakit-3 locality (Lower Triassic; Krasnoyarsk Krai, Russia). The holotype shows a well-preserved full-body imprint with partially visible dorsal and nearly complete ventral aspects. Previous well-preserved complete specimens of this family are known only from the Jurassic. The general body structure of Anakitium storozhenkoi is in many ways similar to later Archostemata, including recent Cupedidae and Ommatidae, while the elytral structure exhibits several unique and likely ancestral characters. Discovery of Anakitium provides new insights into the morphology of Asiocoleidae, which was previously known mainly from isolated elytra. The taxonomic placement of A. storozhenkoi and certain genera within Asiocoleidae is discussed.

ABSTRACT The Sacanana locality, from the Early Miocene (Colhuehuapian South American Land Mammal Age) of the Sarmiento Formation (Chubut Province, Argentina), offers a notable fossil record of mammals, including primates, rodents, ungulates and metatherians. The caviomorph fauna is primarily known through a few well-preserved specimens, while its general diversity remains largely unexamined. Here we report new fossil rodents from Sacanana, collected with strict stratigraphic control, including the first mention of Perimys erutus and Perimys intermedius, a skull fragment of Chinchilloidea indet. and a specimen of the known Soriamys ganganensis. This contribution increases the diversity of caviomorphs in the locality, from four genera and four species to five genera and six species. In this way, Sacanana is the third Colhuehuapian rodent fauna from the Argentinian Patagonia with the greatest taxonomic diversity after Bryn Gwyn and Gran Barranca. The presence of Perimys in Sacanana extends the geographic distribution of the genus within the Colhuehuapian SALMA. It also provides a new biochron for Perimys erutus and P. intermedius, previously known for the Pinturan and Santacrucian SALMAs (late Early Miocene).

Leptarctus is a morphologically distinctive carnivoran mammal occurring in Miocene deposits of North America and East Asia. In North American Leptarctus is mostly known from the Great Plains and Florida, but the single occurrence in China and recent description of well-preserved specimens in Oregon indicate that the western North American distribution of the genus is understudied. Here I document previously unreported specimens of Leptarctus and review other leptarctines housed in the collections of the University of California Museum of Paleontology (UCMP). Dental materials of at least four species of Leptarctus are present in the UCMP collections, encompassing occurrences from the Hemingfordian to Hemphillian North American Land Mammal Ages, adding to known records in the Great Plains, and expanding the paleogeographic range of L. wortmani into Nevada. Materials representing the genus in California are fragmentary but confirm the presence of L. wortmani in the Black Hawk Ranch locality in the coastal ranges of northern California, and L. ancipidens in the Cajon Valley in the southern Great Basin region of southern California.

An extremely well-preserved specimen of the trace fossil Piscichnus waitemata, commonly interpreted as having been formed through the foraging behaviour of a fish or a mammal using a hydraulic jet from its mouth, occurs in heterolithic sandstones and mudstones of tidal flat origin in the Miocene Shirahama Formation, southwestern Japan. While most P. waitemata specimens have been reported as mere dish-, bowl-, or plug-shaped foraging pits, this specimen is accompanied by a lobe of sediment consisting of radially arranged smaller, secondary sediment lobes that partially fringe the upper margin of a plug-like foraging pit. Comparison with modern ray foraging traces allows the lobe to be interpreted as redeposited blown-out sediment from the hydraulic-jet excavation process. As the specimen occurs in a net depositional setting of a prograding tidal flat system, the blown-out sediments, which are commonly obliterated during fossilisation processes due to a variety of processes, including physical erosion and bioturbation, would have successfully passed through the fossilisation barrier. Furthermore, the overall morphology of the unilobed blown-out sediment clearly differs from that formed by rays, which typically exhibits a bilobed morphology. Taking the Early Miocene northwestern Pacific fauna into consideration, the trace maker was likely a large mammal, such as a desmostylid, which is known to have fed on benthic organisms using water flows generated by its oral pump.

Abstract Stephanidae, an early-diverging lineage within the Apocrita (Hymenoptera), occupies a pivotal position in reconstructing the evolutionary trajectory of parasitoid wasps. Despite its critical phylogenetic status as one of the early-diverging hymenopteran families, the group’s early diversification remains poorly constrained due to exceptionally sparse fossil evidence, and the taxonomic placement of some lineages remains controversial. Here, we describe 3 well-preserved specimens from mid-Cretaceous Burmese amber, designated as follows: †Squamastephanus shihongliangi gen. et sp. nov. (†Lagenostephaninae), †Acanthostephanus tenuitubus gen. et sp. nov. (Schlettereriinae), and †Burmastephanus breviceps gen. et sp. nov. (Stephaninae). Combined with maximum parsimony phylogenetic analyses based on morphological data, the topology of Stephanidae is updated, confirming that †Tichostephanus belongs to Gasteruptiidae rather than Stephanidae. The fossil taxa described in this study exhibit a mosaic of plesiomorphic and derived traits that bridge phylogenetic gaps between ancestral and modern lineages. Our findings yield critical insights into the family’s morphological diversification during the Cretaceous.

The earliest skeleton-based gobioid fish, the minute goby †Carlomonnius quasigobius Bannikov and Carnevale, 2016 (13 mm standard length), originates from the Lower Eocene coral reef fish assemblage of Monte Bolca, northern Italy. Resolving its phylogenetic position is key to understanding gobioid evolution. However, previous analyses have yielded contradictory results, placing it either as a possible stem of Butidae or as a potential stem of the Gobiidae + Oxudercidae clade. Here, we describe a second species of †Carlomonnius from Monte Bolca, †C. carnevalei sp. nov., based on a well-preserved complete specimen, and reassess the phylogenetic relationships of †Carlomonnius within a total-evidence framework. For the latter purpose, we expanded previous data sets by adding seven additional extant gobies (six Butidae, one Gobiidae). With a standard length of 12.5 mm, †C. carnevalei sp. nov. ranks among the smallest known goby species, including both fossil and extant forms. Similarly to †C. quasigobius, †C. carnevalei sp. nov. exhibits a mixture of derived (pelvic fins with a spine and four rays) and plesiomorphic (10 abdominal and 14 caudal vertebrae, autogenous haemal spine of the second preural centrum) traits. It differs from its congener by possessing a divided dorsal fin, a slenderer body with an elongated caudal peduncle, a squarish otolith, and distinct pigmentation. Comparative morphology revealed notable similarities between †Carlomonnius and two other coral reef-associated dwarf gobies: †Oniketia Marramà, Giusberti and Carnevale, 2022 (Lower Oligocene) and Eviota (Gobiidae) from the Western Pacific. Bayesian analysis resolved the two †Carlomonnius species as sister taxa (posterior probability [PP] = 0.98) and placed †Carlomonnius as a possible stem Butidae (PP = 0.93). †Oniketia was tentatively resolved as a stem Gobiidae, though this relationship awaits support (PP = 0.85) and is here interpreted with caution. These results suggest that coral reef-associated dwarf gobies had already achieved ecological success early in gobioid evolution and may have arisen through convergent evolution across different lineages. http://zoobank.org/urn:lsid:zoobank.org:pub:FC678569-3643-4CF6-9007-C6D00F16C3A5

This study analyzes petrified wood samples collected from the Bulgarian Black Sea shore near the Byala locality. These specimens originate from the Galata Formation and date to the Chokrakian age (mid-Miocene). The three well-preserved specimens were identified as Cupressinoxylon sp. (cf. Thujoxylon sp.). In contrast, one poorly preserved specimen suggested a dicot structure and was recognized as Populoxylon sp. (cf. Populus tremula L.). The geological characteristics of the Galata Formation in this region are also discussed.