The PDF file includes:

• Supplementary Text
• Fig. S1. Additional specimens of C. spinosa showing details of overall anatomy.
• Fig. S2. Morphology of the palps of Canadia spinosa and Kootenayscolex barbarensis.
• Fig. S3. Gill morphology and attachment in Canadia spinosa.
• Fig. S4. Additional images and camera lucida drawings of anterior and axial nervous system of C. spinosa.
• Fig. S5. Elemental map of USNM83929C.
• Fig. S6. Additional elemental maps of USNM83929B showing the same region as Fig. 2A.
• Fig. S7. Phylogenetic position of C. spinosa based on morphological character matrix using the mkv + gamma model and ancestral state reconstruction.
• Fig. S8. Three-dimensional reconstructions of C. spinosa by Lars Fields.
• Table S1. Details of fossil material analyzed.
• Legend for movie S1
• References (51–76)

Download PDF

Other Supplementary Material for this manuscript includes the following:

• Movie S1 (.mov format). Movie of three-dimensional reconstruction of C. spinosa by Lars Fields.
• Data file S1. Character taxon matrix in NEXUS format.