FIGURE 1. A. Geographical location of the sites from where the studied materials (red stars) come from, showing the Pinar del Río (B), and Artemisa (C) outcrops.
FIGURE 2. Schematic profile of the Capdevila Formation sedimentary succession in the Pinar del Río area, signaling the trace fossil distribution, which include the strata with Scolicia and the bioturbation index (BI) per bed (modified from Villegas-Martín et al., 2014).
FIGURE 3. Terminology used to describe the Scolicia specimens in this study. Preservation of the lower part of the Scolicia burrow, showing the convex central ridge (1), slopes (2), sediment parallel rows (3), ribs (4), sediment parallel strings (5). Preservation of the upper part of echinoid burrow ("Laminites" expression) with meniscate backfill (6) (modified from Uchman, 1995).
FIGURE 4. Main diagnostic features of Scolicia prisca and its morphological variations in the studied specimens. A. Specimens (MNHNCu-96.001292) with narrow convex central ridge tapering at an end and laminated surface, sediment rows at each side of the burrow bottom, slopes with discrete ribs (laminated backfill). B, C. Specimens (MNHNCu-96.003567 in C) with well-preserved laminated backfill and the two sediment parallel strings in B. D. Specimen MNHNCu- 96.001287 lacking the laminated backfill in the slopes and with the convex central ridge partially preserved, but showing discrete sediment rows when the convex central rigde is preserved (black arrow). E. Specimen MNHNCu-96.001297 with a part of the burrow lacking the slopes with ribs (laminated backfill) but showing the two sediment parallel strings (black arrows). F. Specimen MNHNCu-96.00 showing faint lateral slopes, wide central ridge and narrow or discrete sediment rows. Scale bars equal 10 mm.
FIGURE 5. Sample MNHNCu-96.001296 with specimens assigned to Scolicia isp. var. vertebralis. A-B. Specimens showing laminated slopes and a visible median superficial groove (black arrows). C. Cross-section view showing the concave bottom and the bilobate top of the burrow. D. Drawing of the cross-section represent in C. Scale bars equal 10 mm.
FIGURE 6. Scolicia isp. var. laminites. A-B. Specimens with well-preserved laminated backfill in carbonate beds (MNHNCu-96.001295). C-D. Bilobate top with discrete meniscate backfill and median groove (white arrow in D) in medium-grained sandstone beds. C. Specimen (MNHNCu-96.001295) with basal portion similar to S. prisca (white square). E-F. Burrow cross-section showing the preserved parallel strings (white arrows) in E. Scale bars equal 10 mm.
FIGURE 7. Example of overlying of Scolicia cf. prisca specimens (MNHNCu-96.001291) in intensely bioturbated beds, showing the preservation of the central convex ridge with the two sediment rows. Scale bars equal 10 mm.
FIGURE 8. Furrow made by the modern spatangoid Spatangus purpureus (A) in the coast of Greece (depth = 3 m) (photo by Roberto Pillon) resembling Scolicia prisca (black square). Scale bars equal 50 mm. B. Scolicia prisca from Capdevila Formation (early Eocene). Scale bars equal 20 mm.
