Sunrise (6:49 AM): After watching this plant, the sandpaper plant, Davilla kunthii, for an entire month, I was beginning to wonder whether it would ever bloom. But on the evening of January 29, I saw quite a bit of yellow peeking out of the buds and the next morning at sunrise (6:49 on January 30 here in Potrerillos) when I arrived at the plant, the buds were ready to burst into bloom. A few bees were already hovering around the plant.
As the morning progressed and the flowers opened, it became clear there were two kinds of bees interested in this plant – a large one (circled), and a small bee. (or is it?), below. (The image below, as noted by a corresponden- with an Asian name I can’t translate – is a type of hover fly. I have some other images of the small bee, but they’re not clear enough to post.)
8:00 AM: At least a couple dozen bees were buzzing around. By 8:30 there may have been 50 or more. It was clear that the large bee, at least, was collecting pollen. My only image of this so far is fuzzy, but it’s not hard to see the orange pollen sacs.
8:30 AM: the first few weevils. The weevils are the entire reason I was sitting in the shade comfortably, with my coffee and notebook, watching this sandpaper plant put on its spectacular bloom. I had seen and photographed a weevil swarm last year, and Robin Foster of The Field Museum of Chicago suggested I look at the swarm more closely this year. I’m going to be tracking this plant throughout its blooming period to watch for these weevils.
That they are weevils has been verified by Dr. Henry Stockman who is this January at the Smithsonian Tropical Research Institute here in Panama and kindly looked at my images from last year. He suggested that it is possible that these weevils are eating the pollen – which is a rich protein source. As I watched, I could not see whether they were eating, but they certainly did not seem to be collecting it the way the bees were.
By the time the weevils arrived, some of the petals had already dropped from the flowers. The flowers had gone from opening bud at just before 7 AM to fully open flower, to the commencement of petal-dropping at 8:30 AM. One and a half hours. Astonishing!
9:30 AM: The number of bees was down and the number of weevils was up.
10:30 AM: The petals were seriously dropping off. I could hear the petals landing on the sandpaper-like leaves. They sounded like raindrops. There were even fewer bees, but the weevils were still there.
11:15 AM: Nearly all the petals were gone but several weevils stuck around. When the petals fall off, the cup-like green sepals, which underlie the petals, are left behind with the stamens. The weevils seem unperturbed by the absence of petals and simply crawl around the sepals looking for their pollen meal.
1:30 PM: The sepals were closing in on the stamens. A few weevils were still around, hoping to avoid getting trapped in the sepal jaws, I assume.
4:00 PM: The sepals are completely closed around the stamens. I saw one forlorn weevil crawling around on the sepal surfaces. Some sepals qwew separated enough to show yellow – they’re the ones that were bursting with petals to open the next day.
What a day for a plant! I’m sure Darwin would have loved the show. Remember his study of the “sleeping” leaves of the little machete plant, Erythrina? I wonder what he would have made of the opening and closing jaws of these sepals.




This is amazing! And all in one single day!
Nature is just wonderful….
Thanks for sharing!
/Helen
Hello HelenJ,
Thank you for commenting. I’m still astounded by this plant, too, and I’m watching it daily. Today it closed its sepals even earlier than it did two days ago. Whew. I’m tempted to call it the “fastest flower in the universe,” but who knows – there may be faster ones!

Mary
This extraordinary plant puts to rest the notion that life moves along sluggishly in the tropics–at least among the “smaller majority.” Have you heard of the 19th-century entomologist Jean Henri Fabre? Your careful attention to the animal life on this plant reminds me of him. I suspect that you’d enjoy his work.
~Shelley
Shelley -
How felicitous that you should have mentioned Fabre. A friend of mine has leant me “The Insect World of J. Henri Fabre.” I guess it’s time to start reading it – right after I finish “Between Earth and Sky,” by Nalini Nadkarni, which I had been resisting reading but which I find mostly wonderful, so far.
While on the topic of books, I’ll mention that, so far (again), my favorite plant book of all time is Francis Hallé’s “In Praise of Plants.” Wrenches one’s view of the natural world around.
Dios Mio! This was amazing and quite fascinating. In the past I have passed by the sandpaper plant in various stages of what you described and photographed in the blog entry. Who would have known the fast life it leads!
Thank you for your patience in documenting this and sharing it.
Hi Michael,
That day with the plant was one of the most pleasant days of my life. I’m now just tracking the plant at certain times each day, but I think before the blooming is over, I’ll find another day to just sit with it. It was a little like watching a tide-pool. If you sit there long enough, watching, you pretty soon see the world as from the eyes of one of its residents.
Mary
Felicitous indeed! And I first heard about “In Praise of Plants” only a day or two ago. As I read the description at Amazon, I wondered if I should take the plunge. Now I think I shall.
~Shelley
Shelley,
I hope you enjoy the book half as much as I did and do.
Mary
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I hit this on search
Amazed to read about the life of flower.Incredible Plant!
Wondeful documentation.
I’m about halfway through A Naturalist in Costa Rica, by Alexander Skutch, who also described the flowering of Davilla, in poetic terms but without pictures. Your website provides both the pictures and the further story of the (sometimes frustrated) weevils. Magnificent job!
Thank you, Win.
A Naturalist in Costa Rica is one of those books that’s been on my wish list for quite some time. Your comment is just the incentive I needed to go ahead and buy it. Thanks!