Figure 1. Characteristics of an ancestral flowering plant.

Floral diagram of the Jurassic fossil Nanjinganthus (left), and the characteristics for the flower, perianth and gynoecium of the ancestral flowering plant as predicted by Endress and Doyle (E&D), Sauquet et al. (S), and Taylor (T). The floral diagram is our interpretation of the fossil and it shows (starting at the outside): one bract and two fused bracteole (green); two scales (orange); a whorl of five sepals, which could be four (green); a second whorl of five petals, which again could be four (orange); five fused carpels (which could be four) forming an inferior ovary/epigynous flower (olive green and black) that contains two ovules/seeds (black triangles) that are attached to the outer walls of the ovary; it is also possible for there to be one or three ovules/seeds. The characteristics of Nanjinganthus shown in green in the three lists are consistent with Endress and Doyle, Sauquet et al., and Taylor; the characteristics shown in orange are only consistent with Taylor, and those shown in crimson are not consistent with any of these three sources. Floral diagram created with the Floral Diagram Generator at http://kvetnidiagram.8u.cz/odiagramech_en.php