SUPPLEMENTARY INFORMATION doi:10.1038/nature12017 Supplementary Information 1. Spartobranchus tenuis (Walcott, 1911) from the Burgess Shale Type specimens. a-d, Lectotype, USNM 108494, specimen missing proboscis and terminal portion of trunk; a-b (part), c-d (counterpart). Paralectotypes, USNM 553526, two fragmentary specimens, the most complete (1) shows the posterior portion of the pharyngeal area and the anterior part of the trunk, the second specimen (2) is a poorly preserved fragment of trunk. Abbreviations see Fig. 1. Photography: Direct light (a+c), crosspolarized light (b+d+e). Scale bars = 5 mm. Notes: Ottoia tenuis was originally described based on four specimens (Walcott, 1911). Unfortunately, none of his specimens was figured and no collection numbers were provided in his 1911 WWW.NATURE.COM/NATURE 1
RESEARCH SUPPLEMENTARY INFORMATION figured and no collection numbers were provided in his 1911 publication. We were unable to locate any written evidence of these four specimens in the collections of invertebrate paleontology at the Smithsonian Institution. The number USNM 108494 was assigned in 1942 to designate three pieces as non-figured co-types, two of them being part and counterpart of the same specimen, the third piece having no counterpart. All specimens came from locality 35k. (corresponding to the phyllopod bed, today s Walcott Quarry). Since there is no doubt that Walcott collected these specimens and that the specimen with both part and counterpart corresponds closely in shape and size to Walcott s description, this specimen is hereby assigned as the Lectotype under the number USNM 108494. The other piece with no counterpart, originally labeled USNM 108494, is renumbered USNM 553526 to avoid confusion and becomes now the Paralectotypes (with two specimens). 2 WWW.NATURE.COM/NATURE
SUPPLEMENTARY INFORMATION RESEARCH W W W. N A T U R E. C O M / N A T U R E 3
RESEARCH SUPPLEMENTARY INFORMATION Supplementary Information 2. Spartobranchus tenuis (Walcott, 1911) from the Burgess Shale preservation and clusters. Preservation: Specimens are preserved as flat carbonaceous compressions usually with the trunk appearing more reflective or darker than the rest of the body (i.e. Fig. 1a, SI.1-2,4). The flexible nature of the specimens, variations in angle of burial and preservation, precludes precise morphological measurements. Most specimens were probably buried alive but there is also evidence of tearing and 4 WWW.NATURE.COM/NATURE
SUPPLEMENTARY INFORMATION RESEARCH precludes precise morphological measurements. Most specimens were probably buried alive but there is also evidence of tearing and breakage, in particular of the proboscis (i.e. Fig. 1j,l, SI.1-2,4), pharyngeal areas and some of the tubes (i.e. Fig. 2i, SI.4,5a) suggesting decay and transport. In many cases, however, transport would have been minimal judging by large clusters of specimens that show no evidence of preferred orientation or sorting (i.e. SI.2,4). Figures: a, USNM 203057. b-c, USNM 202183 (part) 202493 (counterpart), specimen within white rectangle enlarged in Fig. 1f. d-e, USNM 202781, specimen within white rectangle enlarged in Fig. 1e. Photography: Direct light (b+e), cross-polarized light (a+c+d). Scale bars in cm: a = 3; b, d, e = 1. Supplementary Information 3 (caption). Spartobranchus sp. from the Upper part of the Wheeler Formation (Drum Mountains, Juab County), Utah. a-b, part and counterpart of incomplete specimen in a tube, ROM 61130. Abbreviations see Fig. 1. Scale bar = 5 mm. (specimen courtesy Robert Gaines). WWW.NATURE.COM/NATURE 5
RESEARCH SUPPLEMENTARY INFORMATION Supplementary Information 4 (caption). Spartobranchus tenuis (Walcott, 1911) from the Burgess Shale Individual worms, portions within white rectangle enlarged in Fig. 1. a, USNM 202861, see close up Fig. 1b. b, GSC 136961, see close up Fig. 1c. c, ROM 62124, see 6 WWW.NATURE.COM/NATURE
SUPPLEMENTARY INFORMATION RESEARCH within white rectangle enlarged in Fig. 1. a, USNM 202861, see close up Fig. 1b. b, GSC 136961, see close up Fig. 1c. c, ROM 62124, see close up Fig. 1d. d, ROM 62126, see close up Fig. 1i. e, USNM 202472, see close up Fig. 1j. f, ROM 62127, see close up Fig. 1k. Abbreviations see Fig. 1. Scale bars in cm: a, d, f = 1; b, c, e = 0.5. WWW.NATURE.COM/NATURE 7
RESEARCH SUPPLEMENTARY INFORMATION Supplementary Information 5 (caption). Spartobranchus tenuis (Walcott, 1911) from the Burgess Shale Tubular structures with worms and details of tubes. a, close up of ROM 62129 (see Fig. 2j) showing breakage of the tube. b-d, ROM 62256, c, d close ups of areas within rectangles in picture a emphasizing the fibrous nature of the tubes. e-f, ROM 62255 showing a close up of tube and ring-like 8 WWW.NATURE.COM/NATURE
SUPPLEMENTARY INFORMATION RESEARCH areas within rectangles in picture a emphasizing the fibrous nature of the tubes. e-f, ROM 62255 showing a close up of tube and ring-like structures along the tube. g-h, part and counterpart of ROM 62554. Photography: Direct light (g), cross-polarized light (a-f+h). Pictures of both parts and counterparts were merged in Adobe Photoshop CS6 using the Apply Image function and darken blending mode in b. Abbreviations see Fig. 1. Scale bars in cm: b,e,g,h = 0.5; a,c,d,f = 0.2. WWW.NATURE.COM/NATURE 9
RESEARCH SUPPLEMENTARY INFORMATION Supplementary Information 6 (caption). Spartobranchus tenuis (Walcott, 1911) from the Burgess Shale Reconstructions by Marianne Collins*. Top, individual specimens within and outside their tubes; bottom, close up of a specimen within its tube. *Reconstruction used with permission from the artist. 10 WWW.NATURE.COM/NATURE