This article was downloaded by: [Institute of Vertebrate Paleontology and Paleoanthropology] On: 10 February 2014, At: 19:32 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Alcheringa: An Australasian Journal of Palaeontology Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/talc20 A sea scorpion claw from the Lower Devonian of China (Chelicerata: Eurypterida) Bo Wang & Zhikun Gai Published online: 13 Jan 2014. To cite this article: Bo Wang & Zhikun Gai , Alcheringa: An Australasian Journal of Palaeontology (2014): A sea scorpion claw from the Lower Devonian of China (Chelicerata: Eurypterida), Alcheringa: An Australasian Journal of Palaeontology, DOI: 10.1080/03115518.2014.870819 To link to this article: http://dx.doi.org/10.1080/03115518.2014.870819 PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions A sea scorpion claw from the Lower Devonian of China (Chelicerata: Eurypterida) BO WANG and ZHIKUN GAI WANG,B.&GAI, Z.K., 2014. A sea scorpion claw from the Lower Devonian of China (Chelicerata: Eurypterida). Alcheringa 38, XX–XX. ISSN 0311–5518. An isolated chelicera (claw) of a pterygotid eurypterid is described from the Lower Devonian Xitun Formation of Yunnan Province, China. It is different from chelicerae of other pterygotids in having four principal denticles and at least four intermediate denticles between the principal denticles on both rami. This Chinese pterygotid, estimated at about 70 cm long, was a top predator that probably hunted small, primitive fishes, such as galeaspids. This discovery represents the first record of Pterygotidae from Asia and the third fossil eurypterid from China. Bo Wang (corresponding author) [[email protected]], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; Steinmann Institute, University of Bonn, 53115 Bonn, Germany; Zhikun Gai [[email protected]], 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. Received 22.10.2013, revised 15.11.2013, accepted 20.11.2013. Key words: Eurypterids, Chelicerae, Pterygotidae, Lower Devonian, China. EURYPTERIDS (sea scorpions) are aquatic, predatory Eurypterids are extremely rare in China and, so far, chelicerates that originated in the early Late Ordovician only two unequivocal specimens have been described. and became extinct during the Late Permian (Dunlop The first Chinese eurypterid was described from the 2010, Tetlie 2007, Vrazo & Braddy 2011). The family Lower Permian of Hebei (Grabau 1920). The second Pterygotidae, comprising about 46 species within five eurypterid was described based on an almost complete genera, is the most speciose clade of eurypterids, and specimen from the lower Silurian Xiaoxiyu Formation Slimonia is inferred to represent the sister group of this of Hunan Province (Tetlie et al. 2007). In addition, family (Tetlie & Briggs 2009). Pterygotidae originated three Eurypterus species were described by Chang in the late early Silurian and went extinct during the (1957) based on several fragments from the Silurian of Middle Devonian (Tetlie 2007). They are a monophy- Hubei Province. However, the original descriptions of letic group characterized by the possession of enlarged these specimens are problematic; thus, a re-examination raptorial chelicerae, non-spiny appendages III–V, undi- is needed to confirm their taxonomic placement (Tetlie vided medial appendages, laterally expanded pretelson et al. 2007). Here, we report an isolated pterygotid and a broad, paddle-like telson (Tetlie & Briggs 2009). chelicera from the Lower Devonian Xitun Formation of Pterygotids were formidable predators with keen binoc- Yunnan, China. It is not only the first record of ular vision and chelicerae adapted for either cutting or Pterygotidae from Asia, but also the third fossil crushing (Laub et al. 2010, Selden 1984). Some of eurypterid from China. them are among the largest arthropods, e.g., the largest Downloaded by [Institute of Vertebrate Paleontology and Paleoanthropology] at 19:32 10 February 2014 individual is estimated as up to 350 cm in length (body length 250 cm plus about 100 cm for the extended che- Materials and methods licerae: Braddy et al. 2008). Pterygotidae were first dis- covered by quarrymen excavating Lower Devonian The specimen IVPP-I4593 is an isolated chelicera with strata of Scotland (Poschmann & Tetlie 2006, Wood- its two rami in articulation collected from the Lower ward 1866–1878). Subsequently, they have been Devonian Xitun Formation of Qujing City, Yunnan described from North America, Europe, Bolivia and Province, southwestern China. The specimen is Australia (Lamsdell & Legg 2010, Miller 2007, Tetlie preserved as a carbonaceous compression in yellowish & Briggs 2009). mudstone. Lower Devonian deposits are well developed in the Qujing area of Yunnan, and are assigned to the Xiaxishancun, Xitun, Guijiatun and Xujiachong formations in stratigraphically ascending order (Dupret © 2014 Association of Australasian Palaeontologists http://dx.doi.org/10.1080/03115518.2014.870819 & Zhu 2008). The Siluro-Devonian boundary is 2 BO WANG and ZHIKUN GAI ALCHERINGA generally placed at the base of the Xiaxishancun The specimen is housed in the Institute of Vertebrate Formation, based on comprehensive studies of spores, Paleontology and Paleoanthropology (IVPP), Chinese conodonts, ostracods, vertebrate assemblages, geochemi- Academy of Sciences. The photograph of the specimen cal stratigraphy, amongst other criteria (Cai et al. 1994, was taken using a Nikon D3X camera, and line Fang et al. 1994, Lamsdell et al. 2013, Wang et al. drawings were finalized using photographs and image- 1992, Zhao et al. 2011). However, Tian et al.(2011) editing software (CorelDRAW X4 and Adobe recently re-analyzed the spore assemblages from the Photoshop CS). The denticle terminology follows Miller Xitun Formation, and argued that the Siluro-Devonian (2007). Abbreviations: td, terminal denticle on fixed boundary should be placed in the middle of the Xitun ramus; d1–d4, principal denticles on fixed ramus, d1, Formation. The Xitun Formation, about 400 m thick, is primary denticle; td′, terminal denticle on free ramus; considered to be Lochkovian in age (Cai et al. 1994, d1′–d4′, principal denticles on free ramus, d1′, primary Xue 2012, Zhao & Zhu 2010). It is composed mainly denticle. The higher classification of eurypterids is of yellowish and greenish grey siltstone, mudstone and based on the phylogenetic analyses of Tetlie & Cuggy marl, and may represent the deposits of a river mouth (2007) and Braddy et al.(2008). and delta front (Cai et al. 1994, Fan & Liu 1995). This formation yields abundant fossils, including spores (Tian et al. 2011), bivalves and brachiopods (Fang Systematic palaeontology et al. 1994), ostracods (Wang et al. 1992), land plants Order EURYPTERIDA Burmeister, 1843 (Cai & Wang 1995, Xue 2012)andfishes (Dupret & Family PTERYGOTIDAE Clarke & Ruedemann, 1912 Zhu 2008, Zhao et al. 2011). Downloaded by [Institute of Vertebrate Paleontology and Paleoanthropology] at 19:32 10 February 2014 Fig. 1 Photograph (A) and line drawing (B) of the Chinese pterygotid chelicera, IVPP-I4593. C, Enlargement of longitudinally grooved and ridged third princi- pal denticle and adjacent interme- diate denticles on the fixed ramus. Scale bar = 10 mm for A and B, 1 mm for C. ALCHERINGA DEVONIAN EURYPTERID CLAW FROM CHINA 3 Fig. 2. Palaeogeographic distribution of Devonian Pterygotidae. Global palaeogeographic reconstruction for the Early Devonian (400 Ma) is after Blakey (2005). Circles represent localities of previously described Devonian Pterygotidae (Tetlie 2007). Star shows the location of the Chinese pterygotid. Pterygotidae gen. et sp. indet. (Fig. 1) Discussion Description. A chelicera comprising the fixed and free Pterygotidae comprises five genera: Acutiramus Ruede- ramus (Fig. 1A, B). Denticles densely aligned, with fine mann, Ciurcopterus Tetlie & Briggs, Erettopterus longitudinal striations (Fig. 1C), without