[PaleoIchthyology • 2026] Bataspis crux • A galeaspid (jawless stem gnathostome) from the Lochkovian of Yunnan with a batwing-shaped head adapted for hydrodynamic efficiency

 

Bataspis crux

Meng, Ferrón, Pisani, Gai & Donoghue, 2026 

 DOI: doi.org/10.1111/pala.70081

Life restoration by Dinghua Yang.

Abstract

Galeaspids are an extinct group of jawless fishes from the Silurian–Devonian of China and northern Vietnam that are key to understanding the origin of vertebrate anatomical innovations. A new eugaleaspid, Bataspis crux gen. et sp. nov., is described based on fossil material from the Lochkovian (Early Devonian) Xishancun Formation of Qujing, Yunnan, China. Bataspis crux possesses a suite of unusual features, especially its bat-wing-like cornual processes that are seamlessly integrated with a brim-like rostral margin without a rostral process, constituting a unique morphology for galeaspids. Maximum parsimony, maximum likelihood and Bayesian phylogenetic inference all support membership in the family Tridensaspidae. We employed computational fluid dynamics to infer the hydrodynamic properties of the headshield of B. crux. Our analysis reveals that this species achieves an exceptionally high lift-to-drag ratio; the highest recorded among known galeaspids. This remarkable efficiency stems from its low drag across various angles of attack, coupled with passive lift generation through the exploitation of the Bernoulli effect by the airfoil cross-section of the cornual processes. This suggests that the species was an effective gliding cruiser, outperforming not only galeaspids but also other stem gnathostomes, such as osteostracans and pteraspidomorphs. These results provide new insights into our understanding of the evolution of Tridensaspidae, the ecological habits of stem gnathostomes and convergence in the evolutionary assembly of the gnathostome bodyplan.

Keywords: galeaspid, phylogenetic analysis, hydrodynamic analysis, lift-to-drag ratio, convergence, morphological function

Bataspis crux, holotype, IVPP V30969: A, internal mould in dorsal view; B, external mould in ventral view.

Abbreviations: c, cornual process; dcm, dorsal commissure; ic, inner cornual process; ifc, infraorbital canal; ldc, lateral dorsal canal; ltc, lateral transverse canal; mdc, median dorsal canal; md.o, median dorsal opening; orb, orbital opening; pi, pineal opening; se, serrated edge; soc2, posterior supraorbital canal; v.mtc, vestige of the median transverse canal; vr, ventral rim.

 All scale bars represent 1 cm.

SYSTEMATIC PALAEONTOLOGY

Subphylum VERTEBRATA-CRANIATA Linnaeus 1758

Infraphylum GNATHOSTOMATA Cope 1889

Subclass GALEASPIDA Tarlo 1967

Order EUGALEASPIFORMES (Liu 1965) Liu 1980

Family TRIDENSASPIDAE Liu 1986

Genus Bataspis nov.

 

Derivation of name: Bat from English, the shape of the cornual processes of Bataspis is similar to the membranous wings in bats.

Type species: Bataspis crux sp. nov.

Differential diagnosis: Bataspis is assigned to Eugaleaspiformes because it exhibits a suite of diagnostic features in morphology: subtriangular headshield with cornual and inner cornual processes, slit-like median dorsal opening, and typical eugaleaspid-type sensory canals. Although Bataspis lacks a rostral angle or process, its diagnostic specialized laterally-projecting processes suggest it differs from the members of Shuyuidae, Sinogaleaspidae, and Eugaleaspidae and can be assigned to Tridensaspidae. Compared with other members of Tridensaspidae, the absence of the rostral angle and the presence of vestiges of the median transverse canal distinguish Bataspis and Falxcornus; the lack of the rostral process constitute a diagnostic difference between Bataspis and the sister group including Pterogonaspis and Tridensaspis. Additionally, Bataspis contains serrations along with the margin connecting the cornual and inner cornual processes and the lateral margins of the median dorsal opening that differ from Falxcornus.

Bataspis crux sp. nov.

 

Derivation of name: The verb ‘to cruise’, in the sense of ‘to move from one side to the other’, is derived (via Norse and Old English) from the Latin crux (cross).

Holotype: A nearly complete headshield and its counterpart, IVPP V30969 (Fig. 1A–B).

Locality & horizon: Near the Qujing Maternal and Child Health Care Hospital Qilin District, Qujing City, Yunnan Province, Xishancun Formation, Cuifengshan Group, Lochkovian, Early Devonian.

Diagnosis: Medium-sized tridensaspid fish; subtriangular headshield; arcuate rostral margin without rostral angle and process; cornual process spine-like, projecting posterolaterally; lobular inner cornual process projecting posteriorly, slightly stronger than cornual process; the angle between the cornual and inner cornual processes exceeding 90° (sickle-like); margin of the headshield connecting the cornual and inner cornual processes serrated; median dorsal opening slit-like (length/width >6) with nearly parallel lateral serrated margins, the posterior margin almost level with the centra of the orbital openings, and its middle part convex forward; orbital opening large, round, and dorsally positioned; pineal opening small, round, beyond the posterior margin of the orbital opening; sensory canal system typical eugaleaspid-type, with three pairs of lateral transverse canals and vestiges of the median transverse canal.

Artistic life restoration of Bataspis crux.

Artwork by Dinghua Yang.

CONCLUSION: 

We describe Bataspis crux, a new species of galeaspid from Xishancun Formation in the Early Devonian (Lochkovian age) of Yunnan, China. Our phylogenetic analyses ally the new genus to the family Tridensaspidae, sister to the clade of Pterogonaspis and Tridensaspis, and sharing with Falxcornus the status as the oldest known tridensaspids. The results of probabilistic phylogenetic methods indicate that more data are needed to clarify the phylogenetic relationships of galeaspids such as the family Shuyuidae. Bataspis crux extends beyond the range of phenotypic variation known previously for galeaspids. The unique morphological features of this bat-like jawless fish result in a high lift-to-drag ratio when at low angles of attack. Our results reveal the breadth of locomotor capabilities available to galeaspids and other jawless stem-gnathostomes, demonstrating that an absence of flexible paired fins was not an impediment to ecological diversity.

Xinyuan Meng, Humberto G. Ferrón, Davide Pisani, Zhikun Gai and Philip C. J. Donoghue. 2026. Bataspis crux, a galeaspid (jawless stem gnathostome) from the Lochkovian of Yunnan with a batwing-shaped head adapted for hydrodynamic efficiency. Palaeontology.  DOI: doi.org/10.1111/pala.70081 [04 August 2026]

[PaleoIchthyology • 2026] Parastylephorus anatoides • A New fossil from the Eocene of Iran provides new insights regarding the evolution of the morphologically bizarre tube-eye fish

 

Parastylephorus anatoides 

Ridolfi, Schrøder, Bahrami, Yazdi, Roa-Varón, Marramà & Carnevale, 2026

 

DOI: doi.org/10.1002/spp2.70114

Artwork by Lucrezia Bonardo

Abstract

Stylephoriformes are a morphologically bizarre lineage of deep-sea fishes, currently represented by a single extant species, Stylephorus chordatus, the so-called tube-eye fish. The phylogenetic relationships of the Stylephoriformes were extensively debated until recent genomic studies proposed a sister-group relationship with the Gadiformes. The tube-eye fish exhibits a suite of highly derived features, including extreme cranial kinesis, a pipette-like oral apparatus specialized for suction feeding, and an elongate, naked ribbon-like body lacking scales. The evolutionary origin of these unique traits is largely unknown, in part due to the complete absence of a fossil record. Here, we describe the first-known fossil of the order Stylephoriformes, from Bartonian (c. 40 Ma) sediments of the Pabdeh Formation, Iran. On the basis of several unique morphological features (edentulous premaxillae and dentary, moderately enlarged pterygoid elements, reduced opercle, elongate ribbon-like body comprising more than 63 vertebrae, eight pectoral-fin rays, absence of basipterygia, and the presence of a complete series of well-developed lateral-line scales) the specimen is assigned to a new genus and species: Parastylephorus anatoides. The fossil exhibits a body physiognomy, oral apparatus and cranial architecture remarkably similar to those of the extant tube-eye, with the most derived features already present and closely comparable in morphology. This suggests that the new fossil represents a good example of long-term morphological stasis among marine teleosts, documenting the persistence of a highly specialized body plan for more than 40 myr.

Keywords: Parastylephorus anatoides, Bartonian, Iran, Pabdeh Formation, Paracanthopterygii

Parastylephorus anatoides gen. et sp. nov., holotype, IUGM 100897, from the Eocene of Babaheydar (Iran). Scale bar represents 10 mm.

SYSTEMATIC PALAEONTOLOGY

Order STYLEPHORIFORMES sensu Miya et al. 2007

Family STYLEPHORIDAE Swainson 1839

Genus Parastylephorus nov.

 

Derivation of name: The genus name is derived from the Greek prefix para- (παρά), meaning ‘near’, combined with Stylephorus, the name of the only currently recognized stylephoriform genus. The name reflects the shared morphological characteristics with Stylephorus.

 

Remarks: As discussed above, the Stylephoriformes are a lineage currently represented by a single extant species, Stylephorus chordatus, which possesses a number of highly derived anatomical features, including a strongly modified buccal apparatus, extremely reduced first two vertebral centra, and a continuous dorsal fin along the entire dorsal margin of the body. The body plan of Parastylephorus gen. nov. closely resembles that of Stylephorus, although it has a set of distinctive traits. These include the maxilla with a well-developed posterior process, the expanded metapterygoid and ectopterygoid, and the reduced size of the opercular bones. In addition, Parastylephorus gen. nov. possesses body squamation, consisting of thin and delicate lateral-line scales, which are completely absent in Stylephorus.

Parastylephorus anatoides sp. nov.

 

Derivation of name: The name is derived from the Latin word Anas, meaning ‘duck’, and the Greek suffix -oides (-οειδής) meaning ‘resembling’ or ‘having the form of’.

Holotype: IUGM 100897 a partially preserved specimen on a single plate 

 

Artistic reconstruction of Parastylephorus anatoides gen. et sp. nov. 

Note that the tubular eyes are based on the condition characteristic of the extant Stylephorus chordatus. 

Artwork by Lucrezia Bonardo.

Lorenzo Ridolfi, Ane Elise Schrøder, Ali Bahrami, Mehdi Yazdi, Adela Roa-Varón, Giuseppe Marramà and Giorgio Carnevale. 2026. A New fossil from the Eocene of Iran provides new insights regarding the evolution of the morphologically bizarre tube-eye fish. Papers in Palaeontology. DOI: doi.org/10.1002/spp2.70114 [11 August 2026]

[PaleoIchthyology • 2026] The Oldest Shark Face—Anatomy of the Devonian elasmobranch Phoebodus

Phoebodus saidselachus Frey, Coates, Ginter, Hairapetian, Rücklin, Jerjen & Klug, 2019

in Klug, Greif, Pohle, Ginter, Coates, Haouz, Lagnaoui, Pople et Frey, 2026. 

www.app.pan.pl/article/item/app012902025.html 

Phoebodus was recognized as the earliest elasmobranch known from articulated remains, a group which constitutes most modern cartilaginous fish comprising sharks, skates and rays. Its elongate body, the presence of two dorsal fins with fin spines, and the elongate head had already been described. Based on spectacularly well-preserved fossils, we add new anatomical information on its exact body proportions, the paired and caudal fins, the dermal denticles, the skull morphology, the endocast, and the gill skeleton. These new skeletons from the Famennian (Upper Devonian) of Morocco (c. 367 Ma) permit a much-improved reconstruction of the anatomy of Phoebodus. The new materials comprise the oldest elasmobranch specimens preserving the complete head in three dimensions. Additionally, the new materials yield information about growth and diet and thus position in the trophic network. Despite the newly coded characters, the phylogenetic position of the genus Phoebodus with the oldest teeth dating to the early Givetian remains that of the oldest stem-elasmobranch in the Bayesian analyses.

Key words: Chondrichthyes, Elasmobranchii, Famennian, ontogeny, exceptional preservation, Fossillagerstätten

Phoebodontiform elasmobranch Phoebodus saidselachus Frey et al., 2019a, middle Famennian, Upper Devonian, southern Maïder, Anti-Atlas, Morocco. A. PIMUZ A/I 5751, prep. T. Imhof, largest individual, nearly complete. B. PIMUZ A/I 5752, prep. T. Imhof, second largest individual, only caudal region missing; for details of the skull see Fig. 2. C. PIMUZ A/I 5753, prep. M. Greif, anterior half, excellent integument, fins and brachial region. D. PIMUZ A/I 5754, prep. R. Roth, two superimposed chondrichthyans; the skull in the middle is Maghriboselache mohamezanei with further remains; the straight, complete skeleton belongs to Phoebodus; the latter preserves the caudal fin. E. PIMUZ A/I 4712, holotype, smallest skeleton, nearly complete, modified after Frey et al. (2019a).

Skeletal reconstruction of the phoebodontiform elasmobranch Phoebodus saidselachus Frey et al., 2019a, middle Famennian, Upper Devonian, southern Maïder, Anti-Atlas, Morocco. A. PIMUZ A/I 5754, caudalis. B, C. PIMUZ A/I 4712, posterior and anterior dorsal fins. D. PIMUZ A/I 5752, anterior dorsal fin. E. PIMUZ A/I 5751, caudalis. F, G. PIMUZ A/I 5753, pectoral fin and branchial basket. H. PIMUZ A/I 5752, head. The photos are not to scale. The scale refers only to the drawing.

Systematic palaeontology 

Chondrichthyes Huxley, 1880 

Elasmobranchii Bonaparte, 1838 

Phoebodontiformes Ginter et al., 2010 

Genus Phoebodus St. John & Worthen, 1875

Reconstructions of an adult female and juvenile male of the phoebodontiform elasmobranch Phoebodus saidselachus Frey et al., 2019a, middle Famennian, Upper Devonian, southern Maïder, Anti-Atlas, Morocco. We incorporated the new anatomical details particularly in the proportions and the fin shapes. The juvenile is reconstructed after the holotype.

  

Christian Klug, Merle Greif, Alexander Pohle, Michał Ginter, Michael I. Coates, Wahiba Bel Haouz, Abdelouahed Lagnaoui, Jonathan Pople, and Linda Frey. 2026. The Oldest Shark Face—Anatomy of the Devonian elasmobranch Phoebodus. Acta Palaeontologica Polonica. 71 (2), 2026: 399-430 DOI:10.4202/app.01290.2025  https://www.app.pan.pl/article/item/app012902025.html

Linda Frey, Michael Coates, Michał Ginter, Vachik Hairapetian, Martin Rücklin, Iwan Jerjen, Christian Klug. 2019. The early elasmobranch Phoebodus: phylogenetic relationships, ecomorphology and a new time-scale for shark evolution. Proc Biol Sci. 286 (1912): 20191336. DOI: doi.org/10.1098/rspb.2019.1336

[PaleoIchthyology • 2026] Asioaspis brachyotus • A New Genus of Polybranchiaspiformes (Galeaspida: stem-Gnathostomes) from the Lower Devonian of Yunnan, China

 

Asioaspis brachyotus

 R.-R. Zhang, N. Zhang, Li, Zhu & Gai, 2026

 

VERTEBRATA ALASIATICA. 64(2);   

 

A new genus and species, Asioaspis brachyotus gen. et sp. nov. of Polybranchiaspiformes, is described from the Lower Devonian Lochkovian Xishancun Formation near Miandian Reservoir, Qujing City, Yunnan Province, China. The new genus is characterized by an elongated ovoid headshield with serrated lateral margins, a small subcircular median dorsal opening, short and laterally projecting cornual processes, an exceptionally broad ventral rim, 12 pairs of branchial fossae, and coarse granular tubercles (~3/mm²). It displays a mosaic of characters of the most primitive polybranchiaspiform (Platylomaspis), derived Polybranchiaspiformes, and even the basal members of the galeaspid family Dayongaspidae. Phylogenetic analysis resolves A. brachyotus as an intermediate taxon between the most primitive Gumuaspidae and other derived Polybranchiaspiformes. Although A. brachyotus also shares the broad ham-brim-like ventral rim with the Gumuaspidae, its other characters are more like other derived Polybranchiaspiformes. In particular, its median dorsal opening and paired orbital openings are not highly close-set on the top of the headshield as in the Gumuaspidae, but rather significantly separated from each other and close to the margin of the ventral rim as in the Pentathyraspidae, Duyunolepididae, and Polybranchiaspidae. These proportions indicate that it was unlikely to have lived a semi-infaunal lifestyle and are more consistent with the epibenthic habit typical of most galeaspids, representing an evolutionary transition from the semi-infaunal benthic to epibenthic lifestyle within Polybranchiaspiformes.

Photograph of Asioaspis brachyotus gen. et sp. nov. from Lower Devonian Xishancun Formation, Qujing, Yunnan in ventral view
A. an incomplete headshield, paratype, IVPP V26676. 2; B. a nearly complete dorsal headshield, holotype, V26676. 1
A. an incomplete dorsal headshield, IVPP V26676.5; B. an incomplete dorsal headshield, V26676.4b

Subclass Galeaspida Tarlo, 1967 

Supraorder Polybranchiaspidida Janvier, 1996 

Order Polybranchiaspiformes Liu, 1965 

Family Asioaspidae fam. nov. 

Type genus Asioaspis gen. nov. 

Differential diagnosis: The Asioaspidae is distinguished from other families of Polybranchiaspiformes by its short, ear-like, and laterally projecting cornual processes. It resembles the Gumuaspidae in having a broad ventral rim, but differs in lacking a rostral process. It differs from the Duyunolepididae, Pentathyraspidae, and Polybranchiaspidae by the presence of a broad ventral rim and further differs from the Duyunolepididae by bearing a pair of broad inner cornual processes. Therefore, a new family, the Asioaspidae fam. nov., is herein established.

Genus Asioaspis gen. nov.  

Type species Asioaspis brachyotus gen. et sp. nov. 

Etymology: Asioaspis is derived from Asio (referring to owls of the genus Asio characterized by prominent ear tufts) plus aspis (Greek shield). 

Diagnosis: Medium-sized polybranchiaspiform characterized by an ovoid headshield with serrated lateral margins; the rostral margin arcuate, but lacking a rostral process; the cornual processes short and projecting laterally; the inner cornual processes large and broad leaf-shaped; median dorsal opening small and subcircular in shape; orbital opening large, round, and dorsally positioned; the sensory canals are well developed, V-shaped posterior supraorbitals and four pairs of lateral transverse canals issuing from the lateral dorsal canal; ventral rim of headshield remarkably broad, 13.5–14.1 mm in width on each side (approximately one half of the width of the entire headshield); a large dome-shaped oralobranchial chamber (a composite chamber with both oral and branchial functions) with 12 pairs of branchial fossae; and ornamentation consists of coarse tubercles (~3/mm²)

 Asioaspis brachyotus gen. et sp. nov. 

Etymology: The brachyotus means short-eared, which is in reference to its short and laterally projecting cornual processes that resemble a pair of short ears on the headshield, as in Asio.

Type locality and horizon: Miandian Reservoir in the Triathlon Sports Park, Qilin District, Qujing City, Yunnan Province, China; Xishancun Formation, lower Lochkovian, Lower Devonian.

Morphological comparison of Polybranchiaspiformes, Dayongaspidida, and Huananaspidiformes

A. Asioaspis; B. Dayongaspis (Zhang et al., 2024); C. Foxaspis (Gai et al., 2023); D. Platylomaspis (redrawn after Gai et al., 2018); E. Rhegmaspis (Gai et al., 2015); F. Rhegmaspis (Gai et al., 2015); G. Nanningaspis (redrawn after Gai et al., 2018)

A–E, G. in dorsal views; F. in ventral view.  

Phylogenetic diagram of Dayongaspidida, Polybranchiaspiformes, and Huananaspidiformes
Dayongaspis (Zhang et al., 2024); Platylomaspis (redrawn after Gai et al., 2018); Nanningaspis (redrawn after Gai et al., 2018); Polybranchiaspis (Liu, 1965); Foxaspis (Gai et al., 2023); Rhegmaspis (Gai et al., 2015).

No scaled

 Life restoration of Asioaspis brachyotus gen. et sp. nov. 

ZHANG Rui-Rui, ZHANG Ning, LI Qiang, ZHU Min and GAI Zhi-Kun. 2026. Asioaspis, A New Genus of Polybranchiaspiformes (Galeaspida, stem-Gnathostomes) from the Lower Devonian of Yunnan, China.  VERTEBRATA PALASIATICA. 64(2); 137-150.  DOI: 10.19615/j.cnki.2096-9899.260113 [20 April 2026] 

https://www.vertpala.ac.cn/EN/10.19615/j.cnki.2096-9899.260113

[PaleoIchthyology • 2026] New Data on the sarcopterygian Koharalepis jarviki (Tetrapodomorpha: Canowindridae) from the Late Devonian of Antarctica, revealed via Synchrotron and Neutron Tomography

 

Koharalepis jarviki Young & Ritchie, 1992  
3D rendering of Koharalepis jarviki (AMF 54325) from neutron tomographic data.

  in Mensforth, Long, Bevitt et Clement, 2026. 

DOI: doi.org/10.3389/fevo.2026.1765271

Artwork: Thomas Turner

Abstract

Introduction: The ‘osteolepiforms’ are an extinct order of lobe-finned fishes that had a cosmopolitan distribution, which are often considered for their proximity to the vertebrate water-to-land transition. The canowindrids are an East Gondwanan clade of tetrapodomorph fishes that exhibit a high level of endemism. However, due to the rarity of canowindrid material and their taphonomy, there is only a single representative preserved wholly in 3D and thus suitable for investigation via modern non-invasive tomography.

Methods: Here we present an updated description of the holotype of Koharalepis jarviki, a canowindrid collected from the Late Devonian Aztec Siltstone formation in Mt Crean, Antarctica, elucidated via a combination of synchrotron and neutron tomography.

Results and discussion: New elements of the braincase, palate, mandible and axial skeleton are revealed for the first time, and previously reported anatomy including the dermal skull and position of the orbits are confirmed. A partial braincase and endocast has been reconstructed, enabling rare insight into the neural anatomy of Koharalepis. Phylogenetic analysis confirms Koharalepis as a member of the Canowindridae with Harajicadectes zhumini recovered as sister taxon. The canowindrids occupy a region of the phylogenetic tree with ‘osteolepidid’ taxa and megalichthyids, crownward of rhizodonts but below tristichopterids and elpistostegalids. This work provides greater support for the taxonomic characters and phylogenetic position of the enigmatic canowindrid family, and the 3D preservation of this material has enabled us to infer some behavioural and ecological insight.

Keywords: 3D modelling, canowindrid, Devonian, endocast, neutron tomography, phylogenetic analysis, Sarcopterygii, tetrapodomorph

3D rendering of Koharalepis jarviki (AMF 54325) from neutron tomographic data in (A) dorsal view, (B) ventral view, (C) anterior view, (D) left lateral view and (E) posterior view.

Et, extra temporal; Ju, jugal; L.Ex, lateral extrascapular; M.Ex, median extrascapular; Op, operculum; Par, parietal; Po, postorbital; PP, postparietal; Sclm, supracleithrum; Sq, squamosal.

Life reconstruction of the Devonian tetrapodomorph fish Koharalepis jarviki.

Artwork: Thomas Turner/Flinders University

 Koharalepis jarviki Young & Ritchie, 1992

Corinne L. Mensforth, John A. Long, Joseph J. Bevitt and Alice M. Clement. 2026. New Data on the sarcopterygian Koharalepis jarviki (Tetrapodomorpha; Canowindridae) from the Late Devonian of Antarctica, revealed via Synchrotron and Neutron Tomography. Front. Ecol. Evol. (14); DOI: doi.org/10.3389/fevo.2026.1765271 [16 April 2026]

[PaleoIchthyology • 2026] Eosteus chongqingensis • The Oldest articulated Bony Fish from the early Silurian period

 

 Eosteus chongqingensis

Y.-A. Zhu, Chen, Li, Zhao, Zhou, Jia, Y.-L. Yu, H.-X. Yu, Wei, Ahlberg, Lu & M. Zhu, 2026

DOI: doi.org/10.1038/s41586-026-10125-2

Life reconstruction by NICE PaleoVislab, IVPP

Abstract

Osteichthyans, comprising sarcopterygians and actinopterygians, dominate modern vertebrate biodiversity, yet their pre-Devonian fossil record remains scarce and fragmentary. The oldest articulated sarcopterygian and stem osteichthyan date to the late Silurian, whereas undisputed actinopterygian fossils in articulation appear only in the Middle Devonian. Here we report an articulated, near-complete osteichthyan from the early Silurian Chongqing Lagerstätte (approximately 436 million years ago), representing the oldest osteichthyan occurrence including microfossils. This tiny fish exhibits a fusiform, generalized osteichthyan body outline, with plesiomorphic osteichthyan characters, including the lack of lepidotrichia and the presence of serial median dorsal plates, pectoral and dorsal fin spines and an anal fin spine reported previously exclusively in stem chondrichthyans and one placoderm. It also displays features, such as a single dorsal fin and caudal fulcra, seen commonly in actinopterygians. Bayesian inference and the 50% majority rule consensus of the maximum-parsimony analysis place the new fish on the osteichthyan stem, whereas the strict consensus leaves its position unresolved within osteichthyans. This discovery increases Silurian osteichthyan diversity and further populates the osteichthyan stem group. The morphological disparity among early osteichthyans implies a more extensive Silurian to Early Devonian radiation of bony fishes than previous lines of evidence suggested.

Morphological evolution of early jawed vertebrates, showing the position of Eosteus and Megamastax among stem bony fishes. 

Eosteus chongqingensis

Life reconstruction of the oldest osteichthyan Eosteus chongqingensis.

 Credit: NICE PaleoVislab, IVPP

Life reconstruction of the biggest Silurian vertebrate Megamastax amblyodus.

Credit: Image by NICE PaleoVislab, IVPP

 

You-An Zhu, Yang Chen, Qiang Li, Wen-Jin Zhao, Zheng-Da Zhou, Lian-Tao Jia, Yi-Lun Yu, Han-Xin Yu, Guang-Biao Wei, Per E. Ahlberg, Jing Lu and Min Zhu. 2026. The Oldest articulated Bony Fish from the early Silurian period. Nature. 651; 128–134. DOI: doi.org/10.1038/s41586-026-10125-2 [04 March 2026]

[PaleoIchthyology • 2025] Apolithabatis seioma • Insights into Stem Batomorphii: A New holomorphic Ray (Chondrichthyes: Elasmobranchii) from the upper Jurassic of Germany

 

Apolithabatis seioma   

Türtscher, Jambura, Spindler & Kriwet, 2025 

     

DOI: doi.org/10.1371/journal.pone.0310174 

 facebook.com: Frederik Spindler

Abstract

The Late Jurassic fossil deposits of southern Germany, collectively known as the ’Solnhofen Archipelago’, are one of the world’s most important sources of Mesozoic vertebrates. Complete skeletons of cartilaginous fishes (Chondrichthyes), whose skeletal remains are rare in the fossil record and therefore all the more valuable, are represented, among others, by exceptionally well-preserved rays (superorder Batomorphii). Despite their potential for research in several areas, including taxonomy, morphology, ecology, and phylogeny, the number of studies on these chondrichthyans is still very limited. Here, we identify a previously unknown ray, †Apolithabatis seioma gen. et sp. nov., which represents the first record of a ray species from the upper Kimmeridgian of Painten, Germany, and thus the oldest Late Jurassic ray taxon from Germany based on skeletal remains. This new batomorph is characterised by a unique body shape and a combination of skeletal features that distinguish it readily from all other known Late Jurassic rays. Two different morphometric approaches confirm differences in body shape and proportions to all known Late Jurassic conspecifics. We thus extend the recent taxonomic revision of these rays and include all described holomorphic specimens in a phylogenetic framework using strict cladistic principles. The phylogenetic analysis reveals all Late Jurassic batomorphs to represent a monophyletic group, for which we introduce the new order Apolithabatiformes, which is sister to all other batomorphs representing a stem group. While the phylogenetic relationships within Apolithabatiformes ord. nov. remain largely unresolved, †Apolithabatis gen. nov. is placed as the sister to †Aellopobatis. This highlights that, despite considerable progress in our understanding of the diversity and phylogeny of early rays, difficulties remain in establishing robust relationships within batomorphs. We therefore emphasise the importance of comprehensive studies of completely preserved fossil cartilaginous fishes to obtain a better understanding of chondrichthyan evolution and their systematics in deep time. 

Systematic palaeontology

Class CHONDRICHTHYES Huxley, 1880 

Subclass ELASMOBRANCHII Bonaparte, 1838  

Cohort EUSELACHII Hay, 1902 

Subcohort NEOSELACHII Compagno, 1977 

Superorder BATOMORPHII Cappetta, 1980 

†APOLITHABATIFORMES ord. nov.

We consequently propose a new order, †Apolithabatiformes ord. nov., which includes the single family, †Spathobatidae with the genera †Aellopobatis, †Apolithabatis gen. nov., †Asterodermus, †Belemnobatis, †Kimmerobatis, and †Spathobatis. This order represents the most plesiomorphic clade within Batomorphii being placed on the stem of the total group Batomorphii. It is possible that the hitherto undescribed Late Jurassic batomorph from Argentina, previously considered merely as Batomorphii indet. by Cione (1999) [14], also belongs to this order, which, however, can only be clarified by a detailed examination of the specimen.

Type species. †Apolithabatis seioma gen. et sp. nov.

Included taxa: †Aellopobatis bavarica, †Apolithabatis seioma gen. et sp. nov., †Asterodermus platypterus, †Belemnobatis spp., †Kimmerobatis etchesi, †Spathobatis spp.

Etymology: The name ’Apolithabatiformes’ is composed of two Greek words, i.e., ’aπολίθωμα’ (apolíthoma) meaning ’fossil’ and ’βατίς’ (batís) meaning ’ray’ or ’skate’.

Diagnostic characters. Elongated mesopterygium contiguous with propterygium and similar in shape; lateral articulation of antorbital cartilages (if present) to nasal capsules; two true fin spines anterior to dorsal fins (absent in some taxa);

Family †SPATHOBATIDAE Dames, 1888 

†APOLITHABATIS gen. nov.

Type species. †Apolithabatis seioma gen. et sp. nov.

 Etymology: Identical to that of the order †Apolithabatiformes (see above): the genus name ’Apolithabatis’ is composed of two Greek words, i.e., ’Απολίθωμα’ (apolíthoma) meaning ’fossil’, and ’βατίς’ (batís) meaning ’ray’ or ’skate’.

Stratigraphic and geographic distribution: Only known from the upper Kimmeridgian (Upper Jurassic) of the ’Solnhofen Archipelago’ (Painten), Bavaria, Germany.

Diagnosis: A guitarfish-like batomorph unique in having the following combination of characters: heart-shaped disc that is wider than long; pointed snout; antorbital cartilages present but reaching less than halfway between the nasal capsules and the propterygium; vertebral centra extending less than half of the synarcual length; large mesopterygium tangent to the propterygium; 40 pectoral radials (9 propterygial, 11 mesopterygial, 20 metapterygial); no pectoral radials articulate directly with the scapulocoracoid between the meso- and metapterygium; pectoral radials segmented in up to five segments; at least 16 pairs of ribs; 19 basipterygial radials (including one compound radial); puboischiadic bar curved anteriorly; no postpelvic processes present; broad and triangular lateral prepelvic processes; well-developed and plate-like haemal and supraneural spines; conspicuous bulge-like structure formed by the supraneural spines in front of each dorsal fin; no fin spines present.

†APOLITHABATIS SEIOMA gen. et sp. nov.

Environmental reconstruction showing †Apolithabatis seioma gen. et sp. nov. in association with a juvenile pleurosaurid.

     Julia Türtscher, Patrick L. Jambura, Frederik Spindler and Jürgen Kriwet. 2025. Insights into Stem Batomorphii: A New holomorphic Ray (Chondrichthyes, Elasmobranchii) from the upper Jurassic of Germany. PLoS ONE. 20(1): e0310174. DOI: doi.org/10.1371/journal.pone.0310174

  facebook.com/FrederikSpindler7/posts/9011371638932562

 

[PaleoIchthyology • 2025] Sooinichthys varii • A New otophysan from the Tlayúa Quarry, Mexico: A North American clue to the early Diversification of this group of Freshwater Fishes

 

Sooinichthys varii

Alvarado-Ortega, Otero & Mayrinck, 2025

DOI: doi.org/10.1002/spp2.70056   

 Researchgate.net/publication/398619176

Abstract

We describe a new genus and species, Sooinichthys varii, based on well-preserved specimens from the Albian marine limestones of Tlayúa Quarry, Mexico. This fish possesses a Weberian apparatus, supporting its inclusion in the clade Otophysi, and a unique combination of skeletal features not found in any living or extinct known otophysan group. This new species represents the first known Early Cretaceous otophysan discovered in North America and one of the oldest found worldwide. Our findings enhance our understanding of the early diversity within the Otophysan group. The new species is significant for ongoing discussions about the history of Otophysi because it highlights a geographical region where the otophysan fossil record is scarce; therefore, it may help answer questions about the relationships between fossils and living species, their geographic distribution, the transition from shallow marine waters to inland environments, and the ecological factors that contributed to their diversity as the most varied group of freshwater fish on Earth.

Keywords: Albian, Tlayúa, Otophysi, Sooinichthys varii, Mexico

Sooinichthys varii

  

Genus Sooinichthys nov. 

Derivation of name. The genus name originates from the Mixtec words So’o (meaning ‘ear’) and ini (meaning ‘internal’), combined with the Greek ichthys (meaning ‘fish’), which togetherform ‘fish with an inner ear’. The name is pronounced /sɒˈ.ɒ.ɪn.ɪk.hi.ə.s/. 

Jesús Alvarado-Ortega, Olga Otero and Diogo Mayrinck. 2025. A New otophysan from the Tlayúa Quarry, Mexico: A North American clue to the early Diversification of this group of Freshwater Fishes. Papers in Palaeontology. DOI: doi.org/10.1002/spp2.70056  [11 December 2025]

 Researchgate.net/publication/398619176_A_new_otophysan_from_the_Tlayua_Quarry_Mexico

x.com/ThePalAss/status/1999592430652248192

[PaleoIchthyology • 2025] Pseudocorax heteroserratus • Pseudocorax (Chondrichthyes: Lamniformes: Pseudocoracidae) in the Upper Maastrichtian Phosphates of Khouribga Province, Morocco

 

Pseudocorax heteroserratus

Egli, Goode, Rempert & Rego, 2025

 DOI: doi.org/10.1017/jpa.2025.10183  

 Researchgate.net/publication/397832548

Abstract

A new species of Pseudocorax (Lamniformes, Pseudocoracidae), Pseudocorax heteroserratus n. sp., is described from the upper Maastrichtian phosphates of Morocco. This novel taxon is recognized by a large sample of isolated teeth collected from the upper Couche III layer at the Sidi Chennane quarry in the Oulad Abdoun Basin, Khouribga Province, Morocco. P. heteroserratus is differentiated from other Pseudocorax species by bearing a mesiodistally elongated tooth base, broad crown, and highly variable serrations. The variability in number and extent of serrations along the carinae ranges from completely absent to fully serrated and finely to coarsely serrated, raising speculation on broader Pseudocorax phylogenetics and as to whether the genesis of serrations within Pseudocorax occurred in a singular progressive event or rather from two distinct events. The morphological variability within the new species highlights the importance of large sample sizes in selachian odontological studies using isolated teeth.

Systematic paleontology

Class Chondrichthyes Huxley, Reference Huxley, 1880

Subclass Elasmobranchii Bonaparte, Reference Bonaparte, 1838

Cohort Euselachii Hay, Reference Hay, 1902

Subcohort Neoselachii Compagno, Reference Compagno, 1977

Order Lamniformes Berg, Reference Berg, 1958

Family Pseudocoracidae Cappetta, Reference Cappetta, 2012

Genus Pseudocorax Priem, Reference Priem, 1897

Type species: Pseudocorax affinis (Münster in Agassiz, Reference Agassiz1843), from the upper Maastrichtian, Netherlands.

 Upper anterior Pseudocorax heteroserratus n. sp. 
 (1–5) MMNS VP-12820 (holotype), upper left anterior tooth in (1) lingual, (2) basal, (3) apical, (4) profile, and (5) labial views.
(6–10) MMNS VP-12827.01, upper left anterior tooth in (6) lingual, (7) basal, (8) apical, (9) profile, and (10) labial views. Scale bars = 5 mm.

Pseudocorax heteroserratus new species 

Diagnosis: Crown and tooth base mesiodistally expanded, especially along upper and lower jaw anterior teeth. Mesial shoulder generally more prominent along basal crown, extending further apically. Variable serrations, from absent to full and coarse to fine, regardless of jaw position or potential ontogenetic stage. Deep basal margin on tooth base with variable tooth base lobe morphology.

Occurrence: Upper Couche III layer of the Oulad Abdoun Basin, Sidi Chennane quarry, near Oued Zem, Khouribga Province, Morocco.

 

Etymology: “Hetero-”, Latin for “different”, and “serratus” for “serrations,” highlighting the variability in the presence and size of serrations along the crown.

 Upper lateroposterior Pseudocorax heteroserratus n. sp. teeth.
(1–5) MMNS VP-12823 (paratype), upper left lateroposterior tooth in (1) lingual, (2) basal, (3) apical, (4) profile, and (5) labial views. (6–10) MMNS VP-12827.05, (?) upper right lateroposterior tooth in (6) lingual, (7) basal, (8) apical, (9) profile, and (10) labial views.
(11–15) MMNS VP- 12827,06, (?) upper left lateroposterior tooth in (11) lingual, (12) basal, (13) apical, (14) profile, and (15) labial views. (16–20) MMNS VP-12827.07, upper left lateroposterior tooth in (16) lingual, (17) basal, (18) apical, (19) profile, and (20) labial views.
(21–25) MMNS VP-12827.08, upper right lateroposterior tooth in (21) lingual, (22) basal, (23) apical, (24) profile, and (25) labial views. (26–30) MMNS VP-12827.09, upper left lateroposterior tooth in (26) lingual, (27) basal, (28) apical, (29) profile, and (30) labial. Scale bars = 5 mm.

Hunter Chase Egli, Benjamin Goode, Trevor Rempert and Christopher Rego. 2025. Pseudocorax (Chondrichthyes, Lamniformes, Pseudocoracidae) in the Upper Maastrichtian phosphates of Khouribga Province, Morocco. Journal of Paleontology. Journal of Paleontology. DOI: doi.org/10.1017/jpa.2025.10183  [21 November 2025]

 Researchgate.net/publication/397832548_Pseudocorax_in_the_Upper_Maastrichtian_phosphates_of_Khouribga_Province_Morocco 

 

Non-technical Summary: A new species of extinct shark, Pseudocorax heteroserratus n. sp., has been identified through isolated teeth from fossil-rich Cretaceous rock in Morocco. Unlike previously known Pseudocorax species, this new species is distinguishable through its broad crown, elongated tooth base, and unusually variable serrations. These serrations range from unserrated to coarsely serrated and provide new insights into Pseudocorax evolutionary history. It raises the question of whether serrations in this lineage evolved gradually in a continuous process or from multiple independent origins. The findings of this study emphasize how large sample sizes of shark teeth are critical in palaeoichthyology, especially when species are known only from their teeth.