Excerpts from Jim Conrad's
Naturalist Newsletter

from the June 11, 2017 Newsletter issued from Rancho Regensis north of Valladolid, Yucatán, MÉXICO
HINTONIA VINE
Each morning as soon as it's light enough to see the ground, the dogs and I jog along the little trail shown below:

HINTONIA OCTOMERA, flowers littering trail

That trail leads goes for about a kilometer before connecting with the main north/south highway between Río Lagartos on the coast and Valladolid about 24kms south of us. You can imagine what fun the dogs have sniffing scents left by critters following the trail the previous night, and always there are things I need to stop a moment and sniff or look at myself. One morning what caught my attention was the cluster of egg-size, funnel-shaped, white corollas littering the path as seen in the above photo.

The blossoms were falling from a woody vine thick as my wrist where it wrapped around the trunk of the tree on the above picture's right side. Up in the tree, the stem branched and one offshoot snaked out over the trail and continued wandering through the forest's canopy on the other side of the road for as far as I could see. Standing on the trail and looking straight up I could see the flowers shown below:

HINTONIA OCTOMERA, flowers and leaves

Notice how this vine's leaves cluster at the tips of the tstem's side branches. Also, the corollas display eight or so lobes instead of the more normal five or six. A view into a flower's mouth reveals several long, white, slender stamens, as seen below:

HINTONIA OCTOMERA, flower from front

This woody vine with opposite leaves, flowers with inferior ovaries, and stems with triangular stipules connecting opposite petiole bases, was clearly a member of the big Coffee or Madder Family, the Rubiaceae. Its woody stem and twig-tip-clustered leaves reminded me of the commonly occurring genus Randia. However, the flowers were all wrong for Randia. This was something new for me -- a fine way to begin a day!

It turned out to be HINTONIA OCTOMERA, a southern Mexico, northern Central American specialty with no established English name, so we'll just call it Hintonia. There's another Hintonia species in Mexico but its flowers display six corolla lobes, not this one's eight. This one's eight lobes are something special, a little unusual and unexpected.