Ornithophily and Extraforal Color Patters in Columnea florida Morton (Gesneriaceae)
Hummingbirds, such as the Little Hermit (Phaethornis longuemareus) and the Green-Crowned Brilliant (Heliodoxa jacula) apparently are attracted to the hidden flowers of Columnea florida Morton (Gesneriaceae) by two conspicuous red spots located on the upper surface near the apex of the large leaves. This extrafloral attraction mechanism, in which the attracting unit, or leaf, does not simply simulate a portion of the flower, seems to be a new and unique type of hummingbird pollination system.
Jones, C. Eugene Jr. and Rich, Pat Vickers
"Ornithophily and Extraforal Color Patters in Columnea florida Morton (Gesneriaceae),"
Bulletin of the Southern California Academy of Sciences:
Available at: https://scholar.oxy.edu/scas/vol71/iss3/2