A New Dayongaspid Galeaspid from the Silurian of the Lower Yangtze Region: Implications for Biogeography and the Evolution of Key Adaptations in Galeaspids

Yumeng Zhang; Xianren Shan; Xianghong Lin; Zhikun Gai; Philip C. J. Donoghue

doi:10.1007/s12583-026-0504-6

Volume 37 Issue 1

Feb 2026

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Journal of Earth Science > 2026 > 37(1): 303-316.

Yumeng Zhang, Xianren Shan, Xianghong Lin, Zhikun Gai, Philip C. J. Donoghue. A New Dayongaspid Galeaspid from the Silurian of the Lower Yangtze Region: Implications for Biogeography and the Evolution of Key Adaptations in Galeaspids. Journal of Earth Science, 2026, 37(1): 303-316. doi: 10.1007/s12583-026-0504-6

Citation:

Yumeng Zhang, Xianren Shan, Xianghong Lin, Zhikun Gai, Philip C. J. Donoghue. A New Dayongaspid Galeaspid from the Silurian of the Lower Yangtze Region: Implications for Biogeography and the Evolution of Key Adaptations in Galeaspids. Journal of Earth Science, 2026, 37(1): 303-316. doi: 10.1007/s12583-026-0504-6

Citation:

Yumeng Zhang, Xianren Shan, Xianghong Lin, Zhikun Gai, Philip C. J. Donoghue. A New Dayongaspid Galeaspid from the Silurian of the Lower Yangtze Region: Implications for Biogeography and the Evolution of Key Adaptations in Galeaspids. Journal of Earth Science, 2026, 37(1): 303-316. doi: 10.1007/s12583-026-0504-6

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A New Dayongaspid Galeaspid from the Silurian of the Lower Yangtze Region: Implications for Biogeography and the Evolution of Key Adaptations in Galeaspids

doi: 10.1007/s12583-026-0504-6

Yumeng Zhang^{1, 2
,},
Xianren Shan^3
,,
Xianghong Lin^{1, 4},
Zhikun Gai^{1, 2
,
,
,},
Philip C. J. Donoghue^{3
,
,
,}

1.
Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China
2.
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100044, China
3.
Bristol Palaeobiology Group, School of Earth Sciences, University of Bristol, Bristol BS8 1TQ, UK
4.
Yunnan Key Laboratory for Palaeobiology, Institute of Palaeontology, Yunnan University, Kunming 650091, China

More Information

Corresponding author: Zhikun Gai, gaizhikun@ivpp.ac.cn; Philip C. J. Donoghue, phil.donoghue@bristol.ac.uk
Received Date: 23 Jul 2025
Accepted Date: 14 Nov 2025

Available Online: 13 Feb 2026

Issue Publish Date: 28 Feb 2026

Abstract

Abstract

Galeaspids are an extinct group of jawless armored fishes that are integral to understanding the origin of anatomical innovations of jawed vertebrates. Resolving the nature of the jawless ancestor of jawed vertebrates requires resolution of the anatomy of the earliest galeaspids, which is currently poorly known. Here we describe a new dayongaspid, Xihaiaspis wuningensis gen. et sp. nov., from the Early Telychian (Early Silurian) Qingshui Formation of Lixi Town, Wuning County, Jiujiang City, Jiangxi Province, China. This first report of dayongaspids from the Lower Yangtze region supports the relative proximity of, and faunal exchange between, South China and Tarim during the Early Telychian. It also informs on the monophyly of Dayongaspidae and the early branching position of this family within Galeaspida. In particular, Xihaiaspis wuningensis gen. et sp. nov. provides insights into the nature of the last common ancestor of Dayongaspiformes, Eugaleaspidiformes and Polybrachiaspiformes. These include the nature of the median dorsal opening, which was transversely oriented and slit-shaped, as well as on the presence of ventro-lateral fin-folds and dorsal spines, which were likely present in the ancestral galeaspid.
- Dayongaspidae,
- Galeaspida,
- Qingshui Formation,
- Silurian,
- Jiangxi Province

Conflict of Interest
The authors declare that they have no conflict of interest.

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References(49)

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