Where: Yunnan, China (25.5° N, 103.7° E: paleocoordinates 6.4° N, 131.3° E)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Xiaxishancun Formation, Lochkovian (419.2 - 410.8 Ma)

• Lower part of the Xiaxishancun Formation. A Pridoli age was suggested for the Xiaxishancun Formation based on thelodont microfossil assemblages (Wang, 1997; Rong & Chen, 2000). The palynological study by Tian et al. (2011) also suggested a Pridoli age for this formation. However, the Siluro-Devonian boundary was placed at the base of the Xiaxishancun Formation, based on other comprehensive studies of spores, conodonts (from the underlying Yulongsi Formation), ostracods, vertebrate assemblages, geochemical stratigraphy and others (Wang, Liu & Li, 1992; Fang et al. 1994; Cai et al. 1994; Zhao et al. 2011), and these studies indicate that the Xiaxishancun Formation is early Lochkovian in age. Regarding our new fossil, we tentatively suggest an earliest Lochkovian age, but a Pridoli age is also possible.

• group of beds-level stratigraphic resolution

Environment/lithology: marine; lithified, gray, green mudstone

Size class: macrofossils

Collection methods: Repository: Peking University (PKU)

Primary reference: J. C. Lamsdell, J. Z. Xue, and P. A. Selden. 2013. A horseshoe crab (Arthropoda: Chelicerata: Xiphosura) from the Lower Devonian (Lochkovian) of Yunnan, China. Geological Magazine 150:367-370 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 216598: authorized by Matthew Clapham, entered by Matthew Clapham on 20.12.2020, edited by Roy Plotnick

Creative Commons license: CC BY (attribution)