Why John’s Liana Belongs to the Borage Family
Well, Michael stepped in and helped, but no other expert came through with an identification of John’s liana. So with a flurry of emails and image exchanges, we put together an argument that the liana is in the Boraginaceae family.
First, the characteristics listed by Gentry (all illustrations from John’s plant):
- simple, usually alternate leaves
- leaves and stems with stiff hairs
- strongly one-sided coiled inflorescence (flower cluster)
In John’s plant, the inflorescence is coiled when young and then
it straightens out.
- mostly butterfly-pollinated flowers
These four characteristics strongly pointed toward Boraginaceae. To really nail the family, though, we thought we ought to look at the fruits and seeds. Here’s what the seed site has to say about the Boraginaceae:
- the fruit is either four nutlets or a drupe (fleshy with a thin skin, such as a grape, plum or cherry)
- there are four seeds
Here are just a few of John’s fruit and seed images (click on any for a larger version):
No question that these fruits are drupes, and the last image shows the four seeds. (You’ll also notice some discoloration in the last image. John says that these fruits, once cut, discolor very quickly, like apples only even more quickly.)
For those of you who remember Michael’s liana, by the way, his plant seems not to belong to the Borage Family – the leaves are opposite rather than alternate, although the opposite leaf arrangement does rarely occur in the Boraginaceae. I’m hoping that one day he’ll have time to identify it and let us know what he learns.
The Borage Family is an honorable one, with about 2000 species. It includes the famous flower, the Forget-Me-Not, comfrey, and of course, borage, for which the family was named.
So, can we go any further than family with this plant? Maybe.
Seven genera of the family Boraginaceae are known for Panama (Miller, 1988) – three genera of trees or shrubs, and four genera of herbs, lianas, vines, or clambering shrubs.
Of the four genera we’re interested in,
- if the flower petals are white, green, or yellow green,
- and the plants are woody
- while the fruits are fleshy
the plant belongs to the Tournefortia genus (Miller, 1988). With a name like that, and with the coiled inflorescence, at least in the early stages, I was sure the name had something to do with a “strong turning” as in tourniquet! Well, guess what, the genus was named for a person – Joseph Pitton de Tournefort, 18th century French botanist who was professor of botany at the Jardin des Plantes (Dave’s Garden Botanary). Sometimes you just can’t outguess botanical names.
Tournefortia is well distributed throughout Latin America.
Fourteen species of Tournefortia are known for Panama, so it may take some time before we know which species John’s liana belongs to, but it’s pretty satisfying to get this far.
And one of the neatest finds (for me) is this. While searching online for more information about Tournefortia, my eye was caught by a link to Dangling in the Tournefortia
Who can resist a title like that? Maybe read some poetry while nibbling on the fruits. What do you think, John?
Update:
Michael has succeeded in identifying his vine. It’s Petrea volubilis, also known as the sandpaper vine from its rough leaves. (Image from wikimedia commons.)
P. volubilis is in the Verbenaceae or verbena family – not in the Boraginaceae or borage family. Both Michael and John thought there were significant differences in the leaves between John’s liana and Michael’s liana. I had thought it possible that the leaves came from the same family. Shows you how much I know!
