Excerpts from Jim Conrad's
from the May 30, 2010 Newsletter issued from Hacienda Chichen Resort beside Chichén Itzá Ruins, central Yucatán, MÉXICO
We've encountered Crotons before, back in upland Chiapas, where we ran into the impressive "Blood Tree," Croton draco, famous for the blood-red sap that copiously flows from its slightest wound. You might enjoy reviewing Blood Tree at http://www.backyardnature.net/chiapas/c_draco.htm.
The very common Croton flowering here now is shown with a Ruddy Daggerwing butterfly flitting among its flowers at the top of this page.
Crotons are members of the big, variable Spurge Family, the Euphorbiaceae. Poinsettias, Castor-Bean and the Rubber Tree they used to make rubber from are members of the Spurge Family. Family members often have colored sap (usually white) and flowers that are unisexual, individual plants of some species bearing both male and female flowers (thus being monoecious) or just the flowers of either sex (dioecious).
In the picture, the white flowers around the daggerwing are male flowers. A close-up showing a male blossom with its numerous white stamens is shown below:
In the butterfly picture if you look below the cluster of male flowers you can make out a few female flowers, each consisting of a three-celled ovary that will mature into a three-seeded fruit. The ovaries are topped by old, browning stigmas (where pollen lands to germinate) atop short, thick styles and subtended by a crinkled calyx, and everything invested with a thick mantle of tiny, white scales, which also cover the stem and leaf undersurfaces. All this is shown below:
A list of plants for the contiguous state of Quintana Roo registers eleven Croton species for that state. Also, Croton taxonomy seems to be in a mess. I can't find online photos for several of the species so I can't be sure which species we have here. However, the New York Botanical Garden's Virtual Herbarium provides high-resolution photos of several of the Crotons listed for Quintana Roo, and one of those appears to match ours, though there might be a look-alike species I don't know about. You can see the matching plant at http://sweetgum.nybg.org/vh/specimen.php?irn=22784.
That's CROTON CHICHENENSIS, which I'm calling the Chichen Croton, since no one else seems to have put an English name to it.