A well-preserved sarcopterygian fish skull from the Famennian (Upper Devonian) Shogram Formation, of the Chitral region, northern Pakistan, is described. Collected as a calcareous nodule by J.A. Talent and colleagues, it has been investigated using high-resolution computed tomography to reveal the internal cranial architecture. It represents a new genus and species of tooth-plated, cosmine-covered dipnoan (lungfish), Talentichthys kuragh n. gen. n. sp., distinguished from all previously described Devonian dipnoans by its deep nasal notches, elongate narrow subnasal ridge, and uniquely shaped olfactory cavities. Additional specimens from the type locality, showing additional aspects of morphology, will be necessary to clarify the phylogenetic position of the new form within the Dipnoi. (c) 2026 The Author(s). Published by Elsevier B.V. on behalf of Nanjing Institute of Geology and Palaeontology. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Palaeospondylus gunni Traquair,189 0,is represented by thousands of similarly preserved articulated fossils from the Achannaras quarry(～390 Mya) in Caithness,Scotland.With radically different interpretations of its structure,it has been assigned to almost all major jawless and jawed vertebrate groups.Here we report a new and older species of Palaeospondylus from the Early D evonian of Australia(c.400 Ma),investigated using high-resolution computed tomography Its 3D-preserved braincase demonstrates a combination of primitive gnathostome features including an anteriorly positioned transverse cranial fissure of uncertain homology,a large dorsal fontanelle and a small hypophysial fossa.Contrary to recent interpretations of P.gunni,the new braincase shows that Palaeospondylus lacks both a postorbital process and an intracranial joint.Our new Australian species extends the history of Palaeospondylus back some 10 million years prior to its occurrence in Scotland.The newly identified neurocranial characters have been coded into a phylogenetic analysis that places Palaeospondylus as a sister group of the Chondrichthyes,but some neurocranial characters could indicate a phylogenetic position within the gnathostome stem group.

[This corrects the article DOI: 10.1093/nsr/nwae444.].

A new genus, Jemalongia, is erected for a porolepiform shoulder girdle and associated scales from the Cloghnan Shale at Jemalong Weir, near Forbes in New South Wales, Australia. There is no evidence for the Late Devonian porolepiform Holoptychius that was previously associated with the tetrapod Metaxygnathus at this site. Scales and a partial articulated specimen of Holoptychius sp. from the Famennian Worange Point Formation at Eden on the New South Wales south coast are close to both Holoptychius sp. from East Greenland and Holoptychius nobilissimus from Scotland. However, evidently a species other than Holoptychius sp. is represented by scales in the Hunter Siltstone at Grenfell, central New South Wales. The Jemalong fossils share character states with other scales from Grenfell and Bogan Gate that show features resembling coelacanth scales; a scale attributed to the Devonian coelacanth Gavinia is shown here for comparison. An isolated tooth plate demonstrates a second lungfish taxon at Jemalong, in addition to the denticulate Soederberghia sp. There is insufficient evidence for referring the skull of Soederberghia to the type species Soederberghia groenlandica. Incomplete placoderm remains suggest that a new antiarch taxon may occur at Jemalong. This new evidence suggests that the age of the Jemalong assemblage should be revised downwards to Givetian-Frasnian or older, rather than Famennian as previously interpreted.

When first described based on isolated scales, Ligulalepis was assigned to the Palaeoniscoidea, a basal group of actinopterygians (ray-finned fishes). Recent cladistic analyses, mainly based on skull and neurocranial characters, have mostly recovered the taxon (or, ‘ Ligulalepis ’) as a stem osteichthyan. Here we present information on Ligulalepis dermal elements other than scales and skulls, that include a cheek fragment, a premaxilla, other marginal jaw elements and teeth, an accessory vomer, a partial shoulder girdle, incomplete spine-like elements, and a gular plate. The shoulder girdle and premaxilla compare closely with those of basal actinopterygians, whereas the spine-like element shows some similarity to the distal end of the spines on medial dorsal plates of the Chinese Late Silurian stem osteichthyans Guiyu and Sparalepis , or alternatively to fin rays on the stem osteichthyan Dialipina. One of the jaw elements appears to be a compound jugal plate plus part of the dentate maxilla, an arrangement not previously known in any Devonian stem osteichthyan, or actinopterygian. Histological structure of dermal plates somewhat resembles that of Meemannia , but pore openings in Ligulalepis lead only to the vascular canal network at the base of the ornament layer and not to a pore canal network. Like previous phylogenetic analyses, our analysis incorporating post-cranial dermal skeleton characters also recovered Ligulalepis as a stem osteichthyan.

En este trabajo presentamos un resumen de la estratigrafía y los restos paleontológicos descubiertos a lo largo de los últimos años en la Formación Campo Chico (Devónico), Sierra de Perijá, Venezuela. La Formación Campo Chico está compuesta por areniscas grises a blancas y conglomerados, intercalados con lutitas y algunos carbones. Los sedimentos de esta formación representan un ciclo continental marginal con influencia marina hacia el tope. El espesor total de la formación está cercano a los 450 m. La Formación Campo Chico fue datada en base a asociaciones de mioesporas como Givetiano medio–Frasniano medio. La fauna fósil constituye la primera evidencia devónica en Venezuela, de los tres grandes grupos de peces (antiárquidos, placodermos y dipnoos), con elementos endémicos de afinidad gondwánica. El conjunto paleofloral, dominado por licofitas, tanto en número de especies como en abundancia, es el más diverso reportado para el Devónico en Gondwana y es muy similar al encontrado en el estado de Nueva York, al este de Norteamérica (Euroamérica). Ubicando la localización geográfica de las ocurrencias florales de la Sierra de Perijá y Nueva York en las últimas reconstrucciones paleocontinentales del Devónico, las dos localidades están ubicadas en un cinturón de temperaturas cálidas entre Gondwana y Euroamérica. Una estrecha barrera marina se postula, separando ambas masas, para el tiempo de sedimentación de la Formación Campo Chico.

Our understanding of the earliest evolution of jawed vertebrates depends on a credible phylogenetic framework for the jawed stem gnathostomes collectively known as "placoderms".1 However, their relationships, and whether placoderms represent a single radiation or a paraphyletic array, remain contentious.2-13 This uncertainty is compounded by an uneven understanding of anatomy across the group, particularly of the phylogenetically informative braincase and brain cavity-endocast. Based on new tomographic data, we here describe the endocast and bony labyrinth of Brindabellaspis stensioi from the Early Devonian of New South Wales.14 The taxon was commonly recovered as branching near the base of placoderms.5-9,11,12,15-17 Previous studies of Brindabellaspis emphasized its resemblances with fossil jawless fishes in the braincase anatomy14 and endocast proportions1,18 and its distinctive features were interpreted as autapomorphies, such as the elongated premedian region.19 Although our three-dimensional data confirmed the resemblance of its endocast to those of jawless vertebrates, we discovered that the inner ear and endolymphatic complex display a repertoire of previously unrecognized characters close to modern or crown-group jawed vertebrates, including a pronounced sinus superior and a vertical duct that connects the endolymphatic sac and the labyrinth cavity. Both parsimony and Bayesian analyses suggest that prevailing hypotheses of placoderm relationships are unstable, with newly revealed anatomy pointing to a radical revision of early gnathostome evolution. Our results call into question the appropriateness of arthrodire-like placoderms as models of primitive gnathostome anatomy and raise questions of homology relating to key cranial features.

The quantification of membrane-associated biomolecular interactions is crucial to our understanding of various cellular processes. State-of-the-art single-molecule approaches rely largely on the addition of fluorescent labels, which complicates the quantification of the involved stoichiometries and dynamics because of low temporal resolution and the inherent limitations associated with labeling efficiency, photoblinking and photobleaching. Here, we demonstrate dynamic mass photometry, a method for label-free imaging, tracking and mass measurement of individual membrane-associated proteins diffusing on supported lipid bilayers. Application of this method to the membrane remodeling GTPase, dynamin-1, reveals heterogeneous mixtures of dimer-based oligomers, oligomer-dependent mobilities, membrane affinities and (dis)association of individual complexes. These capabilities, together with assay-based advances for studying integral membrane proteins, will enable the elucidation of biomolecular mechanisms in and on lipid bilayers.

Single particle tracking has found broad applications in the life and physical sciences, enabling the observation and characterization of nano- and microscopic motion. Fluorescence-based approaches are ideally suited for high-background environments, such as tracking lipids or proteins in or on cells, due to superior background rejection. Scattering-based detection is preferable when localization precision and imaging speed are paramount due to the in principle infinite photon budget. Here, we show that micromirror-based total internal reflection dark field microscopy enables background suppression previously only reported for interferometric scattering microscopy, resulting in nanometer localization precision at 6 μs exposure time for 20 nm gold nanoparticles with a 25 × 25 μm2 field of view. We demonstrate the capabilities of our implementation by characterizing sub-nanometer deterministic flows of 20 nm gold nanoparticles at liquid-liquid interfaces. Our results approach the optimal combination of background suppression, localization precision, and temporal resolution achievable with pure scattering-based imaging and tracking of nanoparticles at interfaces.

Our understanding of the earliest evolution of jawed vertebrates depends on a credible phylogenetic assessment of the jawed stem gnathostomes collectively known as ‘placoderms’. However, their relationships, and even whether ‘placoderms’ represent a single radiation or a paraphyletic array, remain contentious. Here we describe the endocranial cavity and inner ear of Brindabellaspis stensioi , commonly recovered as a taxon of uncertain affinity branching near the base of ‘placoderms’. While some features of its braincase and endocast resemble those of jawless vertebrates, its inner ear displays a repertoire of crown gnathostome characters. Both parsimony and Bayesian analyses suggest that established hypotheses of ‘placoderm’ relationships are unstable, with newly-revealed anatomy pointing to a potentially radical revision of early gnathostome evolution. Our results call into question the appropriateness of fusiform ‘placoderms’ as models of primitive gnathostome anatomy and raise questions of homology relating to key cranial features. One Sentence Summary The skull of a 400-million-year old fossil fish suggests that hypotheses of early jawed vertebrate relationships might have to be turned on their head.

New Devonian fish remains are described from the lower part of the Gilberton Formation of north Queensland, the first identifiable specimens found since the original specimen was described in 1936. They include the first determinable dermal skull bones from this deposit. Some dermal bones of the trunk armour are closely associated, and of similar size with morphology consistent with coming from the same fish, permitting a provisional reconstruction of the ventral wall of trunk armour. The new morphological evidence indicates a form close to the antiarch Remigolepis, and a likely age of late Famennian for the lower fossiliferous strata of the Gilberton Formation.

AbstractProtein–protein and protein–substrate interactions are critical to function and often depend on factors that are difficult to disentangle. Herein, a combined biochemical and biophysical approach, based on electrically switchable DNA biochips and single‐molecule mass analysis, was used to characterize the DNA binding and protein oligomerization of the transcription factor, forkhead box protein P2 (FOXP2). FOXP2 contains domains commonly involved in nucleic‐acid binding and protein oligomerization, such as a C2H2‐zinc finger (ZF), and a leucine zipper (LZ), whose roles in FOXP2 remain largely unknown. We found that the LZ mediates FOXP2 dimerization via coiled‐coil formation but also contributes to DNA binding. The ZF contributes to protein dimerization when the LZ coiled‐coil is intact, but it is not involved in DNA binding. The forkhead domain (FHD) is the key driver of DNA binding. Our data contributes to understanding the mechanisms behind the transcriptional activity of FOXP2.

Edenopteron, with a lower jaw some 48 cm long, and total length perhaps exceeding 3 m, is the largest Devonian lobe-fin known from semi-articulated remains. New material described from the type locality (Boyds Tower, south of Eden) includes three slightly smaller articulated skulls and jaws, and additional bones of the shoulder girdle. Another articulated skull roof, shoulder girdle and palate is described from a second locality (Hegarty Bay), about 10km south of Boyds Tower. Both localities represent the upper part of the Worange Point Formation, of late Famennian age (uppermost Upper Devonian). The new morphological evidence supports a close relationship to the tristichopterids Mandageria and Cabonnichthys, from the slightly older (Frasnian, Upper Devonian) fossil fish assemblage at Canowindra, New South Wales. Features of the shoulder girdle (supracleithrum, anocleithrum) suggest that Edenopteron is more closely related to Mandageria than Cabonnichthys. Eight characters are used to define a tristichopterid subfamily Mandageriinae, to which Notorhizodon from the Middle Devonian of Antarctica is also referred. The Mandageriinae is endemic to East Gondwana (Australia-Antarctica). In combination with possibly the most primitive tristichopterid, Marsdenichthys from the Frasnian of Victoria, these distributions implicate East Gondwana as a likely place of origin for the entire group. This relates to the major but unresolved question of a possible Gondwana origin for all the land vertebrates (tetrapods). An endemic Gondwanan sub-group (Mandageriinae) of the Devonian fishes closest to land animals (tetrapodomorph tristichopterids) is confirmed. Retention of primitive features (e.g. accessory vomers) points to an earlier origin of the Mandageriinae in East Gondwana, consistent with the Victorian occurrence of another primitive tristichopterid (Marsdenichthys). Edenopteron is confirmed from a second south coast fossil site, and new characters indicate its closest relative is Mandageria from Canowindra, NSW. Congruent evidence of older Gondwanan occurrences in other groups (basal tetrapodomorphs, rhizodontids, canowindrids), and previously dismissed trace fossil evidence (Grampians trackways), implicate South China and East Gondwana as the likely place of origin for all land vertebrates.

Burrow, C.J., Turner, S., Trinajstic, K. & Young, G.C., 27 February 2019. Late Silurian vertebrate microfossils from the Carnarvon Basin, Western Australia. Alcheringa43, 204-219. ISSN 0311-5518.A core sample from the offshore Pendock 1A well, Carnarvon Basin, Western Australia yielded microvertebrate residues at an horizon in the lower part of the Hamelin Formation, dated as late Silurian, ? Ludlow, based on associated conodonts. The fish fauna comprises loganelliiform thelodont scales, the ? stem gnathostome Aberrosquama occidens nov. gen. et sp., the acanthodian Nostolepis sp. aff. N. alta, and the ? stem osteichthyan Andreolepis sp. aff. A. petri. Because of the paucity of the material, and some differences between the Pendock scales and those of established species, a precise age can not be confirmed; however, the composition of the fauna at generic level most closely resembles that of late Silurian (Ludlow) assemblages from northern Eurasia.

The tetrapodomorph fish, Gogonasus andrewsae is a three dimensionally well-preserved sarcopterygian from the Gogo Formation (Frasnian, early Upper Devonian, similar to 380 million years ago) in Western Australia. High-resolution X-ray Micro-Computed Tomography and 3D printouts were used to obtain a digital reconstruction of its shoulder girdle and opercular series. Our new findings show the opercular series in a close fit against the upper bones of the shoulder girdle only if the anocleithrum, supracleithrum and post-temporal are aligned more horizontally than in previous reconstructions. The lowermost subopercular bone also differs, in partly covering the clavicle of the shoulder girdle. The ascending process of the clavicle, and the ventral process of the anocleithrum, do not fit closely inside the cleithrum, and perhaps functioned for ligamentous attachment. A rugose area on the anocleithral process is in a similar relative position to the attachment of a muscle ligament on the shoulder girdle of various living actinopterygians. Our manipulation of 3D printouts permits testing of the morphological fit of extremely fragile acid-etched bones, and indicates a new way to investigate the constructional morphology of one or more mechanical units of the vertebrate skeleton. It is suggested that Micro-CT imaging, reconstruction, visualisation and 3D printing techniques will provide a rigorous new test leading to modification of previous reconstructions of extinct vertebrates that were based on graphical methods and 2D imaging. (C) 2019 Elsevier Ireland Ltd Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. Published by Elsevier B.V. All rights reserved.

Here the posterior cranial portion of the tetrapodomorph Tungsenia from the Lower Devonian (Pragian, ~409 million years ago) of Yunnan, southwest China, is reported for the first time. The pattern of posterior skull roof and the morphology of the otoccipital region of the neurocranium are described in detail, providing precious insight into the combination of cranial characters of the earliest known tetrapodomorph to date. The posterior cranium of Tungseniadisplays a mosaic of features previously linked either to basal dipnomorphs such as Youngolepis(e.g., the well-developed subjugular ridge, the strong adotic process, and the poorly developed fossa bridgei) or to typical tetrapodomorphs (e.g., the lateral dorsal aortae commenced from the median dorsal aorta postcranially). The independent ventral arcual plate is also found in the advanced tetrapodomorph Eusthenopteron. The new endocranial material of Tungsenia further fills in the morphological gap between Tetrapodomorpha (tetrapod lineage) and Dipnomorpha (lungfish lineage) and unveils the sequence of character acquisition during the initial diversification of the tetrapod lineage. The new phylogenetic analysis strongly supports the basalmost position of Tungsenia amongst the tetrapod lineage.

Arthodire placoderms, as a possible sister group of Chinese ‘maxillate’ placoderms plus crown gnathostomes, provide important information regarding early evolution of jaws and teeth. High-resolution computed tomography and digital dissection on a unique articulated 400 million-year-old buchanosteid arthrodire permitsa detailed description of the three types of gnathal elements in basal arthrodires for the first time, giving insights into their morphology and the organization of the associated dentition. In displaying numerous denticle rows (dental fields), the gnathal element morphology is very different from the much-reduced denticulation of higher brachythoracid arthrodires, even though the latter have been used recently to interpret origin and early evolution of teeth. Ossification centres are anterolateral on the anterior supragnathal (attached to the braincase), anteromesial on the posterior supragnathal (attached to the palatoquadrate), and in the central part of the biting portion of the infragnathal (attached to the meckelian cartilage). The latter bone shows no evidence of two ossification centres as has been interpreted for more advanced arthrodires. Denticle rows radiating from the ossification centre form dental fields in all three elements, and are more similar to the gnathal elements of phlyctaeniid and actinolepid arthrodires than to advanced brachythoracids. The new evidence gives insights into the primitive arthrodire condition for comparison with the dermal jaw bones of Chinese ‘maxillate’ placoderms that have been homologised with the premaxilla, maxilla, and dentary of osteichthyans. The new details will help clarify the sequence of character acquisition in the evolution of marginal jaw bones in basal gnathostome groups.