The Most Extensive Devonian Fossil Forest with Small Lycopsid Trees Bearing the Earliest Stigmarian Roots  Deming Wang, Min Qin, Le Liu, Lu Liu, Yi Zhou, Yingying Zhang, Pu Huang, Jinzhuang Xue, Shihui Zhang, Meicen Meng  Current Biology  DOI: 10.1016/j.cub.2019.06.053 Copyright © 2019 Elsevier Ltd Terms and Conditions

Figure 1 Location, Distribution, and Stratigraphy of the Fossil Forest (A) Locality at Xinhang, Guangde of Anhui. (B) Distribution of fossils at two mines near Jianchuan village. The arrow indicates “isolated” in situ stems at west corner of Jianchuan mine. The rectangle indicates part enlarged in (C). (C) Occurrence of lycopsid rhizomorphs or erect stems in Wutong Formation (Leigutai Member) at west and east quarries of Jianchuan mine. The quarry boundaries were extended from 2009 to 2018, when the plant fossils were recorded in their exact positions by mapping. Symbols for plants indicate only their positions, but the plant sizes are not to scale. (D) Stratigraphic column of parts of the Leigutai Member, showing horizons of stems and/or rhizomorphs of in situ lycopsid. Abbreviations are as follows: WQ, west quarry; EQ, east quarry; T (m), thickness (meters). See also Figures S1–S7 and Data S1. Current Biology DOI: (10.1016/j.cub.2019.06.053) Copyright © 2019 Elsevier Ltd Terms and Conditions

Figure 2 In Situ Stems from West Quarry at Jianchuan Mine (A) Highwall in December of 2016, same as Figure S1C, arrows 1, 2, and 5–8 indicating parts in Figures S3F, S3I, and S3K–S3N, respectively; arrows 3 and 4 part in (B). (B) Enlargement of part between arrows 3 and 4 in (A). Arrows 1–13 indicate stems enlarged in (C)–(O), respectively, with arrow 1 also showing a 27-cm-long hammer. (C–O) Enlargement of (B) (arrows 1–13), respectively, with (G) showing stem with leaves. Scale bars are as follows: 2 cm (E, F, H, and J–L); 2 cm diameter of coin in these six and other figures for scale (C, D, G, M, and O); 5 cm, (I and N); 1 m, (B); and 10 m (A). See also Figure S1 and Data S1. Current Biology DOI: (10.1016/j.cub.2019.06.053) Copyright © 2019 Elsevier Ltd Terms and Conditions

Figure 3 In Situ Lycopsid from East Quarry at Jianchuan Mine (A) Highwall in September of 2016, the same as Figure S2D; for explanations of arrows, see Figure S2D. (B) Rock in (A) (arrow 16) with stem bases and rhizomorphs (arrows and rectangle). (C) Side view of rhizomorph in (B) (arrow a). PKUB16153. (D) Rhizomorph in (C) after removal of rock cast in stem base. (E) Four rhizomorphs in (B) (rectangle). (F) Side view of arrowed rhizomorph in (E). (G) Side view of rhizomorph in (B) (arrow b). (H) Rhizomorph in (B) (arrow c). Scale bars: 2 cm (H and coin diameter). See also Figures S2, S4, S5, and S7 and Data S1. Current Biology DOI: (10.1016/j.cub.2019.06.053) Copyright © 2019 Elsevier Ltd Terms and Conditions

Figure 4 Rooting Systems and Erect Stems of Guangdedendron (A–J and L–U) The same as in Data S1.13F, S1.25C, S1.19C, S1.19F, S1.14H, S1.14G, S1.8I, S1.12J, S1.12L, and S1.12M and Figure S3H, Data S1.4B, S1.4F, S1.4G (arrow), S1.18A–S1.18D, S1.18H, and S1.16I, respectively. (A–G) Rooting system with (dichotomous) rhizomorph axes bearing rootlets. (A) Stem base with three rhizomorph axes (bases) visible. PKUB16167d. (B) Dégagement of stem in Data S1.25C (left arrow) and its connected rhizomorph. (C) Stem base with two rhizomorph axes visible. (D) Dégagement of stem base and rhizomorph in Data S1.19F. PKUB16169. (E) Side view of arrowed part in (F). PKUB16166a and PKUB16166c. (F) Top view of the stem base with four dichotomous rhizomorph axes. (G) Stem base with four rhizomorph axes. PKUB16199. (H) Single rhizomorph axis bearing rootlets. PKUB16164 and PKUB16165. (I and J) Two sides (I) and one side (J) of a rhizomorph axis in (H), respectively, showing rootlet scars. PKUB16165. (K–O) In situ erect stems showing leaf bases. (K) Enlargement of arrowed stem in (B). (L) Helically arranged leaf bases in parasiticides. (M) Thick stem. PKUB16062. (N) Stem with leaves. (O) Thick stem. (P–U) Erect stems (in fallen blocks) that show dichotomies. (P and Q) Lateral view of a dichotomous stem. (R) Face view of arrowed part in (Q), showing two branches of stem. (S) Mid-upper part of the stem in (Q) after dégagement. (T) Arrow indicating dichotomous point of a stem. (U) Arrow indicating dichotomous point of a stem and extension of branches along bedding plane. Scale bars: 1 cm (I and J), 2 cm (D, F–H, K–N, and coin diameter), and 5 cm (C and T). See also Figures S1–S3 and Data S1. Current Biology DOI: (10.1016/j.cub.2019.06.053) Copyright © 2019 Elsevier Ltd Terms and Conditions

Figure 5 Stems, Branches, and Strobili of Guangdedendron (A) Stem with leaf bases and leaves. PKUB16156. (B) Dichotomous stem. (C) Terminal branch with leaves. PKUB16052c. (D) Strobili lying vertical to bedding plane and probably in a pair. The same as in Data S1.14K is shown. (E) Two terminal strobili. PKUB16051. (F) A pair of terminal strobili. (G) A single terminal strobilus. The same as in Data S1.24N is shown. PKUB16001a. (H) Distal part of strobilus in (G), showing sporophylls and megaspores. (I) Counterpart of right strobilus in (D). PKUB16177. (J) Enlargement of (I) (arrow) showing megaspores. (K) SEM (scanning electron micrograph), a megaspore with trilete mark. Scale bars are as follows: 0.5 mm (K), 1 mm (J), 5 mm (H), 1 cm (C and I), and 2 cm (A, B, D–G). See also Figure S2 and Data S1. Current Biology DOI: (10.1016/j.cub.2019.06.053) Copyright © 2019 Elsevier Ltd Terms and Conditions

Figure 6 Reconstruction of Guangdedendron A juvenile plant (left) and a mature one (right). Current Biology DOI: (10.1016/j.cub.2019.06.053) Copyright © 2019 Elsevier Ltd Terms and Conditions

Figure 7 Reconstruction of Xinhang Forest Landscape Monospecific lycopsid forest in coastal habitat. Current Biology DOI: (10.1016/j.cub.2019.06.053) Copyright © 2019 Elsevier Ltd Terms and Conditions