Selaginella papillosa Valdespino. A Section of lower surface of stem showing lateral leaves and axillar leaf B lateral leaf, lower surface C proximal half of lateral leaf, upper surface (same leaf shown in B) D distal half of lateral leaf, upper surface (same leaf shown in B) E detail of lateral leaf, lower surface; note elongate, papillate idioblasts with papillae interconnected (a) F detail of outer half of median leaf, lower surface; note elongate, papillate idioblasts (a) G axillary leaf and portion of lateral leaves, lower surface H portion of proximal half of axillary leaf, lower surface (same leaf shown in G) I distal half of axillary leaf, lower surface (same leaf shown in G). A–I taken from the holotype.