Excerpts from Jim Conrad's
Naturalist Newsletter

from the June 21, 2015 Newsletter issued from Río Lagartos, on the north-central coast of Yucatán, MÉXICO

After the rainy season's first rain, but a day before the deluge of last weekend and the legendary hoards of mosquitoes that followed, at the mangroves' edge it was a delight to see all the newly sprouting and flowering shrubs and small trees. It felt exactly like mid-spring days up North, except mind-numbingly hot and humid. A particularly springy-looking , head high tree or bush I hadn't seen before is shown below:

RANDIA OBCORDATA, tree in flower

In the context of the transition zone, or "ecotone," where we were, between the mangrove and savanna/ranchland ecosystems, this plant's herbage was exceptionally dark green, lustrous and dense, so that its clusters of white flowers provided a very appealing visual contrast, as seen below:

RANDIA OBCORDATA, flowers among leaves

The flowers themselves surprised me with their long tubes, which easily broke away from their subtending ovaries, which were "inferior," meaning that the flowers' sexual parts arose atop the ovaries, not below them, as you can see below in a picture where a flower's animal-attracting part has broken from atop its goblet-shaped, green ovary:


Details seen in that photo left me scratching my bald head. Is the large, white item a corolla, or a calyx modified to look like a corolla to an animal pollinator? If it's a corolla, then where are the calyx's sepals, and what's the corolla tube doing turning green at its base? But, what plant in our area could produce inferior ovaries with such long, corolla-like calyx tubes? Breaking open the possible corolla, anthers were found attached at the tube's opening at the level of the green, oblong stigma, as shown below:

RANDIA OBCORDATA, flower longitudinal section

The flower's ovary looks like something in the Coffee Family, the Rubiaceae, but that would mean that the white thing is a corolla, so there must be a calyx, and this flower simply has no decent calyx.

After spending many hours trying to figure out the plant's identity I gave up and asked some friends at CICY, Yucatán state's Center for Scientific Investigation, in Mérida.

RANDIA OBCORDATA, the reply came back, meaning that the little tree/bush was indeed a member of the Coffee Family, so that the white thing was a corolla, and the calyx amounts to no more than the modest rim atop the ovaries seen in the photo. I'm used to Randia flowers having five lobes, not four as on our tree, so maybe something is going on with our tree.

Randia obcordata is fairly widely distributed in arid areas from Texas south through Mexico into southern Central America, and maybe farther. It bears no decent English name, though in Spanish it has several, including Papache Borracho, Papachillo, Altanisa and Crucillo. The latter name, Crucillo, means "Little Cross" of the Catholic kind. Down here any plant whose branches stick out at right angles is liable to be called Crucillo. Our much branching little tree's base stems do make crosses here and there, as seen below:


The funny name Papache Borracho more or less means "Potato Drunk," probably referring to a feature of the fruits, which look like spherical, green apples conspicuously hanging on the stems, and which have been reported as edible, but, if more than two or three are eaten, may make you stagger like a drunk.

Five days after taking the above pictures in which the white flowers are so abundant and eye-catching, after the big rains I returned to find that not a single flower was to be seen on the tree. The tree had had its yearly moment of glory, and now was hard to spot amid all the rest of the mangroves' jungly greenery.

I'd found it and admired it just at the right moment.

from the April 10, 2016 Newsletter issued from Hacienda Chichen Resort beside Chichén Itzá Ruins, central Yucatán MÉXICO

Along a trail through Hacienda Chichen's woods an eight-ft-tall tree (2.5m) bore familiar-looking leaves, shown glowing in early morning sunlight below:


The tree's leaves arose in tufts along the branches, and the branches bore pairs of short, straight spines, and occasional black balls that either could have been old, decaying fruits or insect galls resulting from parasitized smaller fruits, all shown below:

RANDIA OBCORDATA, leaves, thorns and old fruit

The leaves were familiar but the flowers were unlike anything I'd ever seen. They had "inferior ovaries," meaning that the corolla and sexual parts arose atop the ovary instead of at its base, which is the more common condition, and the stamens' anthers peaked up between crinkly-margined corolla lobes, as shown below:

old flower

Below, a front view of the flower better shows the anthers on the rim of the corolla's throat, which either is filled with morning dew, nectar or a combination:

old flower from front

This turns out to be Crucillo, Randia obcordata. The little tree tricked me because when earlier we've seen it its fresh the flowers were pure white, their margins weren't crinkled, and their corolla tubes were longer. I lost some Iding time by not recognizing that I was working with an old blossom turning black.

Still, it's good to show different faces of these species because I suspect I won't be the last to spend a lot of time trying to identify a flower looking like the one in this week's pictures.