Modern representatives of chondrichthyans (cartilaginous fishes) and osteichthyans (bony fishes and tetrapods) have contrasting skeletal anatomies and developmental trajectories1,2,3,4 that underscore the distant evolutionary split5,6,7 of the two clades. Recent work on upper Silurian and Devonian jawed vertebrates7,8,9,10 has revealed similar skeletal conditions that blur the conventional distinctions between osteichthyans, chondrichthyans and their jawed gnathostome ancestors. Here we describe the remains (dermal plates, scales and fin spines) of a chondrichthyan, Fanjingshania renovata gen. et sp. nov., from the lower Silurian of China that pre-date the earliest articulated fossils of jawed vertebrates10,11,12. Fanjingshania possesses dermal shoulder girdle plates and a complement of fin spines that have a striking anatomical similarity to those recorded in a subset of stem chondrichthyans5,7,13 (climatiid ‘acanthodians’14). Uniquely among chondrichthyans, however, it demonstrates osteichthyan-like resorptive shedding of scale odontodes (dermal teeth) and an absence of odontogenic tissues in its spines. Our results identify independent acquisition of these conditions in the chondrichthyan stem group, adding Fanjingshania to an increasing number of taxa7,15 nested within conventionally defined acanthodians16. The discovery of Fanjingshania provides the strongest support yet for a proposed7 early Silurian radiation of jawed vertebrates before their widespread appearance5 in the fossil record in the Lower Devonian series.
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Supplementary data for this study provided as tomography slices (.bmp), volume renderings (.ply) and phylogenetic analyses files (.tnt, .nex, .tre, .rtf, .log, .ckp, .mcmc, .parts, .t, .tprobs, .tstat and .vstat) are available at Figshare (https://doi.org/10.6084/m9.figshare.20366838.v1). The ZooBank LSID code for this publication is urn:lsid:zoobank.org:pub:09B4CB7A-9640-4685-B9C1-97A7B682F45B. The ZooBank LSID code for the new genus Fanjingshania is urn:lsid:zoobank.org:act:71E5E18E-FE0A-41F0-B928-A1019EF92E28. The ZooBank LSID code for the new species Fanjingshania renovata is urn:lsid:zoobank.org:act:E4ED8B95-866A-4D1B-961A-695373908692. Fanjingshania specimens with assigned accession numbers (IVPP V27433.1–V27443.1) are available upon request from the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences.
Dean, M. N., Mull, C. G., Gorb, S. N. & Summers, A. P. Ontogeny of the tessellated skeleton: insight from the skeletal growth of the round stingray Urobatis halleri. J. Anat. 215, 227–239 (2009).
Seidel, R., Blumer, M., Chaumel, J., Amini, S. & Dean, M. N. Endoskeletal mineralization in chimaera and a comparative guide to tessellated cartilage in chondrichthyan fishes (sharks, rays and chimaera). J. R. Soc. Interface 17, 20200474 (2020).
Sire, J. Y., Donoghue, P. C. & Vickaryous, M. K. Origin and evolution of the integumentary skeleton in non‐tetrapod vertebrates. J. Anat. 214, 409–440 (2009).
Witten, P. E. & Huysseune, A. A comparative view on mechanisms and functions of skeletal remodelling in teleost fish, with special emphasis on osteoclasts and their function. Biol. Rev. 84, 315–346 (2009).
Brazeau, M. D. & Friedman, M. The origin and early phylogenetic history of jawed vertebrates. Nature 520, 490–497 (2015).
King, B., Qiao, T., Lee, M. S., Zhu, M. & Long, J. A. Bayesian morphological clock methods resurrect placoderm monophyly and reveal rapid early evolution in jawed vertebrates. Syst. Biol. 66, 499–516 (2017).
Coates, M. I. et al. An early chondrichthyan and the evolutionary assembly of a shark body plan. Proc. R. Soc. B 285, 20172418 (2018).
Brazeau, M. et al. Endochondral bone in an Early Devonian ‘placoderm’ from Mongolia. Nat. Ecol. Evol. 4, 1477–1484 (2020).
Giles, S., Friedman, M. & Brazeau, M. D. Osteichthyan-like cranial conditions in an Early Devonian stem gnathostome. Nature 520, 82–85 (2015).
Zhu, M. et al. A Silurian maxillate placoderm illuminates jaw evolution. Science 354, 334–336 (2016).
Burrow, C. J. & Rudkin, D. Oldest near-complete acanthodian: the first vertebrate from the Silurian Bertie Formation Konservat-Lagerstätte, Ontario. PLoS ONE 9, e104171 (2014).
Zhu, M. et al. The oldest articulated osteichthyan reveals mosaic gnathostome characters. Nature 458, 469–474 (2009).
Dearden, R. P. et al. A revision of Vernicomacanthus Miles with comments on the characters of stem‐group chondrichthyans. Pap. Palaeontol. 7, 1949–1976 (2021).
Burrow, C. J., Newman, M. J., Davidson, R. G. & den Blaauwen, J. L. Redescription of Parexus recurvus, an Early Devonian acanthodian from the Midland Valley of Scotland. Alcheringa 37, 392–414 (2013).
Maisey, J. et al. in Evolution and Development of Fishes (eds Johanson, Z. et al.) 87–109 (Cambridge Univ. Press, 2019).
Denison, R. Acanthodii Vol. 5 (Gustav Fischer, 1979).
Donoghue, P. C. J., Sansom, I. J. & Downs, J. P. Early evolution of vertebrate skeletal tissues and cellular interactions, and the canalization of skeletal development. J. Exp. Zool. B 306, 278–294 (2006).
Giles, S., Rücklin, M. & Donoghue, P. C. Histology of “placoderm” dermal skeletons: implications for the nature of the ancestral gnathostome. J. Morphol. 274, 627–644 (2013).
Zhu, M. et al. A Silurian placoderm with osteichthyan-like marginal jaw bones. Nature 502, 188–193 (2013).
Karatajūtė-Talimaa, V. & Predtechenskyj, N. The distribution of the vertebrates in the Late Ordovician and Early Silurian palaeobasins of the Siberian Platform. Bull. Mus. Natl Hist. Nat. C 17, 39–55 (1995).
Karatajūtė-Talimaa, V. & Smith, M. M. Early acanthodians from the Lower Silurian of Asia. Earth Environ. Sci. Trans. R. Soc. Edinb. 93, 277–299 (2002).
Andreev, P. S. et al. The systematics of the Mongolepidida (Chondrichthyes) and the Ordovician origins of the clade. PeerJ 4, e1850 (2016).
Andreev, P. S. et al. Early Silurian chondrichthyans from the Tarim Basin (Xinjiang, China). PLoS ONE 15, e0228589 (2020).
Sansom, I. J., Aldridge, R. & Smith, M. M. A microvertebrate fauna from the Llandovery of South China. Earth Environ. Sci. Trans. R. Soc. Edinb. 90, 255–272 (2000).
Zhu, M. Early Silurian sinacanths (Chondrichthyes) from China. Palaeontology 41, 157–171 (1998).
Andreev, P. S. et al. Elegestolepis and its kin, the earliest monodontode chondrichthyans. J. Vertebr. Paleont. 37, e1245664 (2016).
Burrow, C. J., Davidson, R. G., Den Blaauwen, J. L. & Newman, M. J. Revision of Climatius reticulatus Agassiz, 1844 (Acanthodii, Climatiidae), from the Lower Devonian of Scotland, based on new histological and morphological data. J. Vertebr. Paleontol. 35, e913421 (2015).
Miles, R. S. Articulated acanthodian fishes from the Old Red Sandstone of England: with a review of the structure and evolution of the acanthodian shoulder-girdle. Bull. Br. Mus. Nat. Hist. Geol. 24, 111–213 (1973).
Andreev, P. S. et al. The oldest gnathostome teeth. Nature https://doi.org/10.1038/s41586-022-05166-2 (2022).
Ginter, M., Hampe, O., Duffin, C. J. & Schultze, H. Chondrichthyes. Paleozoic Elasmobranchii: Teeth Vol. 3D (Dr Friedrich Pfeil, 2010).
Dearden, R. P., Stockey, C. & Brazeau, M. D. The pharynx of the stem-chondrichthyan Ptomacanthus and the early evolution of the gnathostome gill skeleton. Nat. Commun. 10, 2050 (2019).
Burrow, C., den Blaauwen, J., Newman, M. & Davidson, R. The diplacanthid fishes (Acanthodii, Diplacanthiformes, Diplacanthidae) from the Middle Devonian of Scotland. Palaeontol. Electron. 19, 19.1.10A (2016).
Maisey, J. G. et al. Pectoral morphology in Doliodus: bridging the ‘acanthodian’-chondrichthyan divide. Am. Mus. Novit. 3875, 1–15 (2017).
Denison, R. H. Placodermi. Vol. 2 (Gustav Fischer, 1978).
Long, J. A. et al. Copulation in antiarch placoderms and the origin of gnathostome internal fertilization. Nature 517, 196–199 (2015).
Zhu, M. et al. Fossil fishes from China provide first evidence of dermal pelvic girdles in osteichthyans. PLoS ONE 7, e35103 (2012).
Ørvig, T. Some new acanthodian material from the Lower Devonian of Europe. Zool. J. Linn. Soc. 47, 131–153 (1967).
Hanke, G. F. & Wilson, M. V. Anatomy of the Early Devonian acanthodian Brochoadmones milesi based on nearly complete body fossils, with comments on the evolution and development of paired fins. J. Vertebr. Paleontol. 26, 526–537 (2006).
Hanke, G. & Wilson, M. in Morphology, Phylogeny and Paleobiogeography of Fossil Fishes (eds Elliott, D. K. et al.) 159–182 (Dr Friedrich Pfeil, 2010).
Sansom, I. J. & Andreev, P. S. in Evolution and Development of Fishes (eds Johanson, Z. et al.) 59–70 (Cambridge Univ. Press, 2019).
Sansom, I. J., Wang, N.-Z. & Smith, M. The histology and affinities of sinacanthid fishes: primitive gnathostomes from the Silurian of China. Zool. J. Linn. Soc. 144, 379–386 (2005).
Chen, D., Blom, H., Sanchez, S., Tafforeau, P. & Ahlberg, P. E. The stem osteichthyan Andreolepis and the origin of tooth replacement. Nature 539, 237–241 (2016).
Sire, J. Y., Marin, S. & Allizard, F. Comparison of teeth and dermal denticles (odontodes) in the teleost Denticeps clupeoides (Clupeomorpha). J. Morphol. 237, 237–255 (1998).
Doeland, M., Couzens, A. M., Donoghue, P. C. & Rücklin, M. Tooth replacement in early sarcopterygians. R. Soc. Open Sci. 6, 191173 (2019).
Chen, D. et al. The developmental relationship between teeth and dermal odontodes in the most primitive bony fish Lophosteus. eLife 9, e60985 (2020).
Chen, D. et al. Development of cyclic shedding teeth from semi-shedding teeth: the inner dental arcade of the stem osteichthyan Lophosteus. R. Soc. Open Sci. 4, 161084 (2017).
Burrow, C. J., Newman, M., Den Blaauwen, J., Jones, R. & Davidson, R. The Early Devonian ischnacanthiform acanthodian Ischnacanthus gracilis (Egerton, 1861) from the Midland Valley of Scotland. Acta Geol. Pol. 68, 335–362 (2018).
Turner, S., Burrow, C. J. & Warren, A. Gyracanthides hawkinsi sp. nov. (Acanthodii, Gyracanthidae) from the Lower Carboniferous of Queensland, Australia, with a review of gyracanthid taxa. Palaeontology 48, 963–1006 (2005).
Zhao, W.-J. & Zhu, M. Siluro-Devonian vertebrate biostratigraphy and biogeography of China. Palaeoworld 19, 4–26 (2010).
Žigaitė, Ž., Karatajūtė-Talimaa, V. & Blieck, A. Vertebrate microremains from the Lower Silurian of Siberia and Central Asia: palaeobiodiversity and palaeobiogeography. J. Micropalaeont. 30, 97–106 (2011).
Wang, C.-Y. & Aldridge, R. J. Silurian conodonts from the Yangtze Platform, south China. Spec. Pap. Palaeontol. 83, 1–136 (2010).
Wang, C.-C. Joint iterative fast projection matching for fully automatic marker-free alignment of nano-tomography reconstructions. Sci. Rep. 10, 7330 (2020).
Wang, Y. et al. Development and applications of paleontological computed tomography. Vertebrat. PalAsiatic. 57, 84–92 (2019).
Dearden, R. P. The Anatomy and Evolution of “Acanthodian” Stem-Chondrichthyans. PhD thesis, Imperial College London (2018).
Qiao, T., King, B., Long, J. A., Ahlberg, P. E. & Zhu, M. Early gnathostome phylogeny revisited: multiple method consensus. PLoS ONE 11, e0163157 (2016).
Goloboff, P. A. & Catalano, S. A. TNT version 1.5, including a full implementation of phylogenetic morphometrics. Cladistics 32, 221–238 (2016).
Swofford, D. L. PAUP*: Phylogenetic Analysis Using Parsimony* and other methods v.4.0b10 (Sinauer Associates, 2002).
Bapst, D. W. paleotree: an R package for paleontological and phylogenetic analyses of evolution. Methods Ecol. Evol. 3, 803–807 (2012).
Vaškaninová, V. et al. Marginal dentition and multiple dermal jawbones as the ancestral condition of jawed vertebrates. Science 369, 211–216 (2020).
Ronquist, F. & Huelsenbeck, J. P. MrBayes 3: Bayesian phylogenetic inference under mixed models. Bioinformatics 19, 1572–1574 (2003).
Béchard, I., Arsenault, F., Cloutier, R. & Kerr, J. The Devonian placoderm fish Bothriolepis canadensis revisited with three-dimensional digital imagery. Palaeontol. Electron. 17, 17.1.2A (2014).
Pearson, D. M. & Westoll, T. S. The Devonian actinopterygian Cheirolepis Agassiz. Earth Environ. Sci. Trans. R. Soc. Edinb. 70, 337–399 (1979).
Dupret, V. Revision of the genus Kujdanowiaspis Stensiö, 1942 (Placodermi, Arthrodira, “Actinolepida”) from the Lower Devonian of Podolia (Ukraine). Geodiversitas 32, 5–63 (2010).
We thank Y.-M. Hou for the acquisition of the micro-CT X-ray data, Y. Hwu and Y.-T. Weng for performing and assisting with the synchrotron X-ray analyses, and Y. Z. Hu for her comments and advice during the volumetric reconstructions of the specimens. This research was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA19050102 and XDB26000000), the National Natural Science Foundation of China (41530102), the Key Research Program of Frontier Sciences, CAS (QYZDJ-SSW-DQC002), an Open Project Grant of the Key Laboratory of Vertebrate Evolution and Human Origins, IVPP, CAS (LVEHO19001), MOST 108-2116-M-213-001 (Taiwan), Chinese Postdoctoral Science Foundation grant (2019M663440) and the National Synchrotron Radiation Research Center, Taiwan (beamtime project numbers 2019-3-083-1 and 2019-3-185-1).
The authors declare no competing interests.
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Extended data figures and tables
Extended Data Fig. 1 The Shiqian-Tunping section at Leijiatun (Shiqian County, Guizhou Province, China).
Diagram revealing the relationship of the Rongxi to the other Silurian lithostratigraphic units (color coded) exposed at Shiqian-Tunping and the location of the Fanjingshania-bearing beds (depicted in grey, sample 35SQTP) within the sequence.
Extended Data Fig. 2 Head and trunk dermoskeletal elements of Fanjingshania renovata.
Volume renderings based on X-ray microcomputed tomography data (a–c, e, f, h, i), scanning electron micrographs (d, g, j, k) and optical micrographs (l, m). Fused tectal tesserae (V27438.4) in a, crown and b, basal views. c, Broad asymmetrical trunk scale in crown view (V27435.23). d, Asymmetrical trunk scale (V27435.6) in crown view. Incomplete symmetrical trunk scale (V27435.7) in e, crown and f, base views. g, Crown view of an asymmetrical trunk scale (V27435.12). h, Crown view of a symmetrical trunk scale (V27435.24) with a large anterior tubercle. i, Basal view of V27435.24. j, Crown view of a trunk scale (V27435.11) with an anterior replacement odontode. k, Incomplete trunk scale (V27435.9) with an anteriorly excavated crown. l, Section through two fused tectal tesserae (V27438.5). m, Longitudinal section through a trunk scale (V27435.8). Arrowheads point to anterior. ad, atubular dentine; cb, cellular bone; po, primary odontodes; ro, replacement odontode; sb, scale base; sc, scale crown; so, secondary odontodes, tt, tectal tesserae. Scale bars, 1 mm.
Extended Data Fig. 3 Fin spines of Fanjingshania renovata.
Volume renderings based on X-ray microcomputed tomography data (a–t) and optical micrographs (u–x). Incomplete pectoral fin spine (V27437.9) in a, lateral and b, apical lateral view. Incomplete pectoral spine (V27437.10) in (c, d) lateral and e, posterior lateral views. Pelvic fin spine (V27437.11) in f, lateral and g, posterior views. Partial anterior dorsal fin spine (V27437.12) in (h, j) and i, posterior views. Incomplete posterior dorsal fin spine (V27437.13) in k, lateral and l, posterior views. Incomplete anal fin spine (V27437.14) in m, lateral and n, posterior views. (o, p) Incomplete prepelvic fin spine (V27441.4) in lateral views. Prepelvic fin spine (V27441.5) in q, lateral and r, basal lateral views. (s, t) Incomplete prepelvic fin spine (V27441.6) in lateral apical views. u, Transversely sectioned fin spine fragment (V27437.2) shown in part. v, Transversely sectioned apical fragment of a fin spine (V27437.1). w, Enlarged anterior of v, showing detail of the spine’s tissue structure. Portion of a longitudinally sectioned pectoral fin spine (V27437.14). cc, calcified cartilage; cb, cellular bone; lz, lamellar zone; vz, vascular zone. Scale bars, 1 mm (a–t), 0.5 mm (v), 0.25 mm (u), 0.2 mm (x) and 0.05 mm.
Extended Data Fig. 4 Elements of the dermal shoulder girdle of Fanjingshania renovata.
Optical micrographs (a, d, i), scanning electron micrograph (b) and volume renderings based on synchrotron (e–h) and microcomputed (j–l) X-ray tomography data. a, Section through a fragment of a pectoral fin spine wall fused to a partial pinnal plate (V27433.3). b, Fragment of a pectoral fin spine wall fused to a partial pinnal plate (V27433.5) in external view. c, Horizontal virtual section through a partial pinnal plate fused to a pectoral fin spine fragment (V27433.1, holotype). d, Detail of a pectoral fin spine wall (from a sectioned pectoral fin spine fragment fused to a partial pinnal plate, V27433.6). e, Lateral view of an admedian fin spine fused to a pinnal plate fragment (V27434.3). f, Transverse virtual slice through V27434.3 shown in anterior view. g, Lateral view of an incomplete admedian fin spine fused to a fragment of pinnal plate (V27434.1). h, Virtual transverse section through V27434.1 in posterior view. i, Portion of basal wall of an admedian fin spine (V27434.4) sectioned along its long axis, apical to the left. j, Lateral view of two prepectoral spines fused to a partial pinnal plate (V27436.1). k, Vertical virtual slice through V27436.1 in ventral view. l, Lateral view of V27436.1 showing ventral pinnal plate lamina (downturned due to a post-mortem fracture). l, Horizontal virtual slice through the prepectoral spines of V27436.1. Arrowheads point to anterior. admfs, admedian fin spine; al, ascending lamina; bp, basal plate; cb, cellular bone; pfs, pectoral fin spine; pi, pinnal plate; pps, prepectoral spines; s1–4, scales 1–4; sc, scale crown; vl, ventral lamina. Scale bars, 1 mm (a–c, e–h, j–l), 0.5 mm (d) and 0.2 mm (i).
Extended Data Fig. 5 Resorption features in the dermal skeleton of Fanjingshania renovata.
Volume renderings based on synchrotron X-ray tomography data (a–d, f–i), optical micrograph (e) and scanning electron micrograph (i). a, Trunk scale (V27435.10) with an anterior replacement odontode and ‘exploded view’ of the same specimen revealing the resorption surfaces in the scale crown and base. b, Basal view of an asymmetrical trunk scale (V27435.1) and the crown and base of the same specimen in crown aspect demonstrating absence of resorption surfaces in contrast to V27435.10. c, Transverse virtual slice through V27435.10 at the level of the replacement odontode. d, Transverse virtual slice through V27435.1 at the level of the primordial odontode. e, Longitudinally sectioned trunk scale (V27435.4) with an anterior resorption surface. f, A partially resorbed pinnal plate scale highlighted in a dermal shoulder girdle fragment (V27433.1, partial admedian fin spine fused to a fragment of a pinnal plate) shown in external (ventral) view. g, Horizontal virtual slice through the pinnal plate and fin spine wall of V27433.1. h, Vertical virtual slice through the pinnal plate and fin spine wall of V27433.1. i, Partially resorbed pinnal plate scale shown in (f–h) superimposed onto an isolated trunk scale (V27435. 27). Image of resorbed scale reflected and magnified 1.5x the scale in (i). ad, atubular dentine; admfs, admedian fin spine; bp, basal plate; cb, cellular bone; pi, pinnal plate; po, primary odontodes; ro, replacement odontode; rs, resorption surface; sb, scale base; sc, scale crown; so, secondary odontodes. Scale bars, 1 mm (a–d, f–i) and 0.5 mm (e).
Extended Data Fig. 6 Phylogenetic reconstructions of early gnathostomes based on a data matrix of 105 taxa and 292 characters.
a, 50 percent majority-rule and b, strict consensus trees from an analysis performed under parsimony optimality criteria (numbers in (a) and (b) represent 50 percent and above bootstrap support for internal nodes). c, 50 percent majority-rule consensus tree from a Bayesian phylogenetic analysis (numbers represent posterior probability values).
Extended Data Fig. 7 Life reconstruction of Fanjingshania renovata.
Original artwork by Fu Boyuan and Fu Baozhong published with their permission.
Details regarding horizon and locality; specimen descriptions; remarks on the dermoskeletal characters of Fanjingshania; a list of characters; Supplementary Table 1 and Supplementary References. It also contains descriptions for Supplementary Data 1–8, which are available at Figshare (https://doi.org/10.6084/m9.figshare.20366838.v1).
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Andreev, P.S., Sansom, I.J., Li, Q. et al. Spiny chondrichthyan from the lower Silurian of South China. Nature 609, 969–974 (2022). https://doi.org/10.1038/s41586-022-05233-8
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