The Albanerpetontidae are a group of small extinct lissamphibians ranging from the Bathonian to the early Pleistocene. The Upper Jurassic of Portugal is known to yield a large collection of albanerpetontid remains, ascribed to the genus Celtedens. However, recent studies have shown that the frontal bones used for species diagnosis display important intraspecific variation. Here, we describe 468 bones from the Kimmeridgian-Tithonian Lourinh & atilde; Formation, together with thousands of remains from the Guimarota beds of the Kimmeridgian Alcoba & ccedil;a Formation. They support the erection of a new genus and species, Nabia civiscientrix gen. et sp. nov., characterized by a unique combination of five synapomorphies: a bulbous/flabellate outline of the internasal process of the frontal in dorsal or ventral view; no sculpture on the postorbital wing of the parietals; the dorsal condyle of the axis with a recurved edge; the long axis of the iliac shaft strongly tilted posteriorly; and a limited pubic/ischial articulation flaring. This material represents the oldest albanerpetontid species from the Iberian Peninsula and potentially the third described from the Jurassic, during which time it played a major palaeobiogeographical role in relation to Europe, north-western Africa and North America. Our results further confirm the need to revise Celtedens. The material from the Lourinh & atilde; Formation suggests that other multi-specific microfossil vertebrate bonebeds should contain a greater variety of elements than is reported. We stress the need to review unpicked and unidentified material to look for postcranial bones rather than focusing only on cranial elements, as in combination they aid a better characterisation of this group.https://zoobank.org/urn:lsid:zoobank.org:pub:2C0A83C0-93A6-45C5-A2A6-FF6C3AA3975F

Astyanax mexicanus is a small freshwater fish from Mexico. It is of particular interest because in addition to the ancestral surface morph, A. mexicanus has several independently evolved cave populations. These cave morphs have a strikingly different cranial morphology, most notably in the regression of the eyes. Detailed information is available on the development, ossification and morphology of the jaws and on the differences in the sensory systems that underlie the patterns of fusion and fragmentation of the infraorbital series in the skulls of cave (troglomorphic) populations of the species. However, there is limited information on the skeletogenesis of the remaining skull components in the species. The present work aims to fill this gap by providing a detailed comparative description of cranial skeletogenesis in surface and Pachón cave populations of Astyanax mexicanus. We find that, anatomically, cavefish larvae are significantly larger than surface larvae at early stages of development, developing overall larger head structures than surface individuals. Pachón cavefish also follow a heterochronic development with respect to surface populations with slower growth and a delayed ossification process compared to surface morphs.

Polyglyphanodontian lizards were one of the dominant groups among squamates during the Late Cretaceous. They were widely distributed and exhibited a great range of body sizes and high morphological variation. The Asian taxa are preserved mostly as complete or nearly complete skulls or skeletons, therefore providing substantial anatomical information for the clade. Here, we describe a new polyglyphanodontian genus and species from the Upper Cretaceous of Ganzhou Basin, Jiangxi Province, China. The new taxon is diagnosed by its unique dentition, with complex posterior teeth having mesial, distal and lingual expansions, connected by crests and with depressions between. The phylogenetic analyses support an assignment of the new taxon to Polyglyphanodontia, forming an unresolved clade with Polyglyphanodon, Gilmoreteius, Adamisaurus, Tianyusaurus and Yechilacerta, or being a sister taxon to either Adamisaurus or a small clade of Tianyusaurus and Yechilacerta. The cranial and dental morphology suggests the new lizard was omnivorous, contrasting with the specialized herbivory of Tianyusaurus and Yechilacerta from the same region. Moreover, the new lizard is the first polyglyphanodontian taxon from Asia with a complex dentition, which shows similarities to that of some North American taxa, and this may suggest the evolutionary history of Polyglyphanodontia is more complicated than previously thought.

BACKGROUND:Syndromic craniosynostosis, such as Apert and Crouzon syndromes, involve premature fusion of cranial sutures, leading to cranial deformities and potential neurological complications. Posterior cranial vault expansion (PCVE) is commonly used to address intracranial volume (ICV) anomalies in these cases, especially in the posterior fossa region. However, the morphological variation of this region between normal, Apert and Crouzon individuals remains understudied. This study aimed to carry out a detailed morphological analysis of the posterior fossa between the aforementioned groups before and after PCVE. METHODS:Retrospective computed tomography (CT) data from 28 children with Apert (n = 13) and Crouzon (n = 15) syndromes, alongside 51 age-matched controls, were analyzed. Intracranial and posterior fossa volumes (ICV and PFV) were computed pre- and post-operatively. Morphometric shape analyses were conducted for posterior fossa and intracranial cavity using principal component analysis (PCA). RESULTS:Pre-operatively, Apert syndrome patients exhibited larger PFV and ICV compared to Crouzon syndrome patients and controls (e.g., p = 0.009 for pre-operative Apert vs. controls), while Crouzon syndrome patients showed more variability in PFV and ICV. Post-operatively, Apert patients demonstrated significant increases in both PFV and PFV/ICV ratios (e.g., post-operative vs. pre-operative PFV: p < 0.001). In contrast, Crouzon patients exhibited limited improvements in PFV, with PFV/ICV ratios often declining post-surgery (p = 0.890; median post-operative-pre-operative difference = -0.095). PCA revealed distinct intracranial and posterior fossa shape differences between Apert and Crouzon patients. CONCLUSIONS:While PCVE increased posterior fossa volume, it did not appear to improve posterior fossa shape in either Apert or Crouzon patients. Future studies are required to address the limitations of small sample sizes, lack of post-operative data on Chiari anomaly, and surgical variability to further explore possible correlations between the aforementioned parameters.

Cephalopod beaks are remarkable organic structures that play a crucial role in the feeding ecology of these marine molluscs. This study investigates the mechanical properties, microstructure, and elemental composition of beaks from four commercially available cephalopod species: Eledone cirrhosa, Sepia officinalis, Loligo vulgaris, and Sepioteuthis lessoniana. Using nanoindentation, we measured the elastic modulus of the rostrum, revealing that lower beaks are stiffer than upper beaks across all species. Notably, L. vulgaris exhibited the highest stiffness. The study highlights significant intra- and interspecific variability in beak properties, suggesting ecological implications regarding diet and environmental factors. Scanning electron microscopy (SEM) showed a fibrous microstructure with nanoparticles of different sizes, while energy dispersive spectroscopy (EDS) identified carbon, oxygen, and nitrogen as primary elements, along with trace elements like silicon and calcium. These initial results suggest that the relationships between beak structure, composition, and biomechanical properties are likely to be complex and species-specific, underscoring the need for more comprehensive analyses to better understand beak function and its adaptive implications. This research provides new baseline data for comparative studies on cephalopod functional morphology and raises the potential of beaks as tools for ecological and environmental monitoring. We recommend that future studies incorporate larger and developmentally diverse samples to refine our understanding of cephalopod feeding adaptations and their interaction with changing marine environments.

A new genus and species of anguimorph lizard, Zhongyuanxi jiai gen. et sp. nov., is described from the Upper Cretaceous (?Maastrichtian) Qiupa Formation of Henan Province, China. Its holotype specimen is represented by a three-dimensionally preserved partial skull and is described based on micro-CT scans of the overall skull and individual bones. Phylogenetic analyses using Bayesian inference place it as the sister taxon to the Mongolian Aiolosaurus oriens on the stem of Varanidae, whether or not a molecular constraint is applied. One of the more unusual features of Zhongyuanxi jiai is the presence of vomerine teeth, which have been recorded in a single living lizard (Pseudopus) and a small number of fossil anguimorphs, suggesting a more widespread distribution of this character among squamates, especially within Anguimorpha.http://zoobank.org/urn:lsid:zoobank.org:pub:830A9292-B0B9-4852-BAB5-AC1BCC46379C

BACKGROUND:In 2018 the Australian Government launched the world's first National Action Plan for Endometriosis (NAPE). Of its three priorities 'Priority 1' was 'Education and Awareness'. In response, the Pelvic Pain Foundation of Australia was funded to deliver their Periods, Pain and Endometriosis Program (PPEP) Talk to a proportion of Australian schools. Since then, PPEP Talk has been delivered to over 110,000 students. AIMS:This retrospective cross-sectional study investigated students assigned female at birth (AFAB) and the prevalence and impact of period and pelvic pain, interaction with health care services and knowledge of endometriosis. MATERIALS AND METHODS:Multiple choice, pre and post PPEP Talk, paper survey responses between July 2022 and June 2023 were collected from 13,078 students AFAB. RESULTS:52.6% of students reported regular severe period pain. 22.9% of students reported regularly missing school or work with their period. 21.5% of students had presented to a health professional for pain, and 5.7% had presented to an Emergency Department. 5.2% of students reported pelvic pain for more than 10 days per month. The prevalence and impact of period and pelvic pain varied across demographic variables. The proportion of students who knew what endometriosis was rose from 47.8% to 95.5% after the program. CONCLUSIONS:The NAPE's objective to enhance education and awareness of endometriosis and period/pelvic pain was met. 100% of schools who received PPEP Talk want it to return. Wide discrepancies in the prevalence of pain within different demographics were identified, providing previously unknown data to improve and direct services.

Lepidosaurs are an ecologically diverse and speciose group with more than 11 000 living species (squamates and the tuatara). Stem lepidosaurs are known from the Early Triassic onwards, but primarily from very incomplete specimens. Therefore, we have little information on their ecological diversity or the ecological context of deep evolutionary divergences of Lepidosauria. Marmoretta oxoniensis , from the Middle Jurassic of the UK, is one of the most completely known candidate stem lepidosaurs. Previous studies proposed that it may have been semi-aquatic, based primarily on its abundance in marginal marine rocks. We show here that Marmoretta was adapted for climbing, based on the post-cranial anatomy of a partial skeleton, visualized using micro-computed tomography (µCT)—in particular, the steep angles of thoracic zygapophyses, ungual phalanx morphology and elongate penultimate manual phalanges that curve distoventrally along their lengths. Linear discriminant analysis of the partial hand, using a training dataset of hand skeleton measurements and habitat use in extant squamates, returns strong evidence for clinging arboreality and Marmoretta clusters among scansorial/arboreal iguanians in manus shape space. Evidence of arboreality in Marmoretta provides the first information about habitat use in a probable stem lepidosaur and illuminates the vertical structure of ecological communities of the mid-Mesozoic.

Squamates (lizards and snakes) comprise almost 12,000 living species, with wide ecological diversity and a crown group that originated around 190 million years ago1,2. Conflict between morphology and molecular phylogenies indicates a complex pattern of anatomical transformations during early squamate evolution, which remains poorly understood owing to the scarcity of early fossil taxa1,3. Here we present Breugnathair elgolensis gen. et sp. nov., based on a new skeleton from the Middle Jurassic epoch (167 million years ago) of Scotland, which is among the oldest relatively complete fossil squamates. Breugnathair is placed in a new family, Parviraptoridae, an enigmatic group with potential importance for snake origins, that was previously known from very incomplete remains. It displays a mosaic of anatomical traits that is not present in living groups, with head and body proportions similar to varanids (monitor lizards) and snake-like features of the teeth and jaws, alongside primitive traits shared with early-diverging groups such as gekkotans. Phylogenetic analyses of multiple datasets return conflicting results, with parviraptorids either as early toxicoferans (and potentially stem snakes) or as stem squamates that convergently evolved snake-like dental and mandibular traits related to feeding. These findings indicate high levels of homoplasy and experimentation during the initial radiation of squamates and highlight the potential importance of convergent morphological transformations during deep evolutionary divergences.

Osteoderms, skeletal structures in the skin, are found in many animals and serve diverse roles. In some lizards, the bony osteoderm has a capping tissue (CT) whose composition and structure remain unknown. Here, the composition and nanostructure of osteoderms from the Mexican beaded lizard (Heloderma horridum) are investigated. The CT is highly mineralized with an extraordinarily high elastic modulus. Within the osteoderm, a transition zone between capping and bone tissue forms a graded increase in mineralization towards the superficial CT. Unlike other examples of mineralized tissues, the CT demonstrates a new combination of physical properties and nanostructural organization. It displays stiffness and hardness similar to enamel, and hydroxyapatite crystals that are an order of magnitude larger than those within the bone tissue and are, thus, reminiscent of enamel crystals. However, in stark contrast to enamel, the CT displays only minimal preferred orientation of the crystallites. Thus, it achieves very high mechanical properties with enamel-like crystal sizes but with near-isotropic microstructural orientation. The Mexican beaded lizard CT presents a highly unusual structural design resulting in high-performance mechanics. STATEMENT OF SIGNIFICANCE: The stiffest tissue in vertebrates is enamel, which is characterized by large, highly oriented nanocrystals. The less stiff bone has smaller nanocrystals and a lower, but still high degree of texture. The osteoderms of the Mexican beaded lizard are herein investigated by a combination of mechanical testing, spatially resolved X-ray diffraction and fluorescence, and 3D X-ray imaging. Surprisingly, the osteoderms have a capping tissue with enamel-like stiffness, significantly larger crystals than the underlying bone but are much less textured. This provides a new type of design for hard biological tissues.

Osteoderms (ODs) are mineralized tissue embedded within the skin and are particularly common in reptiles. They are generally thought to form a protective layer between the soft tissues of the animal and potential external threats, although other functions have been proposed. The aim of this study was to characterize OD variation across the lizard body. Adults of three lizard species were chosen for this study. After whole body CT scanning of each lizard, single ODs were extracted from 10 different anatomical regions, CT scanned, and characterized using sectioning and nanoindentation. Morphological analysis and material characterization revealed considerable diversity in OD structure across the species investigated. The scincid Tiliqua gigas was the only studied species in which ODs had a similar external morphology across the head and body. Greater osteoderm diversity was found in the gerrhosaurid Broadleysaurus major and the scincid Tribolonotus novaeguineae. Dense capping tissue, like that reported for Heloderma, was found in only one of the three species examined, B. major. Osteoderm structure can be surprisingly complex and variable, both among related taxa, and across the body of individual animals. This raises many questions about OD function but also about the genetic and developmental factors controlling OD shape.

Cephalopods, a diverse class of carnivorous marine predators, exhibit a wide range of feeding behaviours and foraging strategies related to their lifestyle, habitat and morphological adaptations. Their beaks play a crucial role in capturing and processing prey. This study investigates the link between the shape of the rostrum of cephalopod beaks and their function through a mix of experimental and computational approaches. Fourteen upper beak rostrum models from a range of cephalopod species, representing their morphological and ecological diversity, were 3D-printed, and subjected to uniaxial puncture tests. Force and displacement were recorded to estimate puncture ability. Finite Element Analysis (FEA) was used to explore the form–function relationship under loading conditions mimicking biting and pulling, analysing stress patterns across different rostrum morphologies. The results show that rostrum size significantly influenced puncture performance, with smaller rostra requiring less force and displacement for puncturing. However, larger rostra exhibited higher structural stiffness, suggesting increased vulnerability to stress during biting. Morphology-driven tests demonstrated species-specific differences in puncture abilities, with rostrum sharpness playing a crucial role. FEA results further indicated that longer and sharper rostra were more susceptible to stress, potentially impacting their overall structural integrity. The findings highlight the trade-off between rostrum size and sharpness in cephalopod beaks, with implications for prey selection and feeding efficiency. The study contributes to understanding the morpho-functional aspects of cephalopod beaks and their role in prey capture and consumption, shedding light on the evolutionary pressures shaping these remarkable marine predators.

BACKGROUND:Platelets are limited in supply, and the preservation of platelet function during storage remains challenging. Novel storage approaches are being explored to improve platelet quality, extend shelf life, and reduce risk of infection. This study sought to elucidate platelet function in cold-stored apheresis units in additive solution (platelet additive solution [PAS]) and subjected to pathogen reduction (PR) as well as the impact of cytochrome c (cyt c) supplementation. We hypothesized that the PR would decrease stored platelet function, regardless of cyt c supplementation. METHODS:Platelet apheresis units (PAS) were collected (N = 5 volunteers) and divided into PR or no PR (PAS) and supplemented with vehicle or cyt c (100 μM). Units were stored at 4°C for 15 days, sequential aliquots were removed, and platelet/mitochondrial respiratory function and biochemical parameters were analyzed. RESULTS:There was no difference in platelet aggregation in response to adenosine diphosphate between PAS and PR platelets. Aggregation function in response to arachidonic acid was higher in PR versus PAS platelets. Maximum clot strength was not different between PAS and PR from Day 0 to Day 5 but declined in PR platelets on Days 10 and 15. Oxygen consumption declined at the same rate in PAS and PR platelets, while rate of lactate and TCO 2 decrease was greater in PR platelets than in PAS platelets. Supplementation with cyt c did not alter platelet function or biochemical parameters in PAS or PR platelets. CONCLUSION:Platelet additive solution and PR platelets show similar declines in respiratory capacity, and biochemical parameters during cold storage, but PR platelets demonstrated significantly increased arachidonic acid-induced aggregation across all time points. Further understanding this mechanism may provide a means to prolong platelet shelf life.

The fully aquatic Japanese giant salamander (Andrias japonicus) is a member of the Cryptobranchidae, and is currently distributed in western Japan, with other members of this group restricted to China and North America. Their feeding behaviour is characterized by a form of suction feeding that includes asymmetric movements of the jaw and hyobranchial apparatus. Previous studies on the North American species, Cryptobranchus alleganiensis, have suggested that this specialized jaw movement is produced by a flexible quadrate-articular joint combined with a loosely connected lower jaw symphysis including two small fibrocartilaginous pads. However, little is known about this feeding behaviour in the Asian species, nor have the three-dimensional asymmetric jaw movements been fully investigated in any member of Cryptobranchidae. In this study, we explore the asymmetric jaw movements in A. japonicus using three methods: (1) dissection of musculoskeletal structures; (2) filming of feeding behaviour to understand in which situations asymmetric feeding is used; (3) analysis of 3D movement of jaws and skull. In the third component, fresh (from frozen) specimens of A. japonicus were manipulated to replicate asymmetric and symmetric jaw movements, with the specimens CT scanned after each step to obtain the 3D morphology of the jaws at different positions. These positions were combined and their Euler angles from resting (closed) jaw position were calculated for asymmetric or symmetric jaw positions. Our filming revealed that asymmetric jaw movements are linked to the position of the prey in relation to the snout, with the jaw closest to the prey opening asymmetrically. Moreover, this action allows the salamander to simultaneously grasp prey in one side of the mouth while ejecting water on the other side, if the first suction attempt fails. The asymmetric jaw movements are performed mainly by rotation of the mandible about its long axis, with very limited lateral jaw movements. During asymmetric and symmetric jaw movements, the posterior ends of the maxilla and quadrate move slightly. The asymmetric jaw movements are permitted by a mobile quadrate-articular joint formed by wide, round cartilages, and by two small fibrocartilage pads within the jaw symphysis that act as cushions during jaw rotation. Some of these soft tissue structures leave traces on the jaws and skull, allowing feeding mode to be reconstructed in fossil taxa. Understanding cryptobranchid asymmetric jaw movement thus requires a comprehensive assessment of not only the symphysial morphology but also that of other cranial and hyobranchial elements.

Osteoderms (ODs) are calcified organs formed directly within the skin of most major extant tetrapod lineages. Lizards possibly show the greatest diversity in ODs morphology and distribution. ODs are commonly hypothesized to function as a defensive armor. Here we tested the hypothesis that cranial osteoderms also contribute to the mechanics of the skull during biting. A series of in vivo experiments were carried out on three specimens of Tiliqua gigas. Animals were induced to bite a force plate while a single cranial OD was strain gauged. A finite element (FE) model of a related species, Tiliqua scincoides, was developed and used to estimate the level of strain across the same OD as instrumented in the in vivo experiments. FE results were compared to the in vivo data and the FE model was modified to test two hypothetical scenarios in which all ODs were (i) removed from, and (ii) fused to, the skull. In vivo data demonstrated that the ODs were carrying load during biting. The hypothetical FE models showed that when cranial ODs were fused to the skull, the overall strain across the skull arising from biting was reduced. Removing the ODs showed an opposite effect. In summary, our findings suggest that cranial ODs contribute to the mechanics of the skull, even when they are loosely attached.

A fossilized egg anchors an analysis of early egg evolution, suggesting that ancestral amniotes retained eggs for an extended period of development.

Somites are transient structures derived from the pre‐somitic mesoderm (PSM), involving mesenchyme‐to‐epithelial transition (MET) where the cells change their shape and polarize. Using Scanning electron microscopy (SEM), immunocytochemistry and confocal microscopy, we study the progression of these events along the tail‐to‐head axis of the embryo, which mirrors the progression of somitogenesis (younger cells located more caudally). SEM revealed that PSM epithelialization is a gradual process, which begins much earlier than previously thought, starting with the dorsalmost cells, then the medial ones, and then, simultaneously, the ventral and lateral cells, before a somite fully separates from the PSM. The core (internal) cells of the PSM and somites never epithelialize, which suggests that the core cells could be ‘trapped’ within the somitocoele after cells at the surfaces of the PSM undergo MET. Three‐dimensional imaging of the distribution of the cell polarity markers PKCζ, PAR3, ZO1, the Golgi marker GM130 and the apical marker N‐cadherin reveal that the pattern of polarization is distinctive for each marker and for each surface of the PSM, but the order of these events is not the same as the progression of cell elongation. These observations challenge some assumptions underlying existing models of somite formation.