Folks from Australia might consider this post about one of their common wildflowers to be quite dull, so I'll try to keep it interesting, I promise. Above you see one of the species of triggerplant (genus Stylidium), a rare 3-lobed corolla mutant (they typically have four corolla lobes–or "petals"–with a fifth highly reduced). It's column, the fused male and female reproductive organs, has been triggered by the pollinator rooting around in the corolla tube, searching for nectar. The column, which normally rests underneath the flower, springs forward in milliseconds, dusting the unsuspecting pollinator with pollen (or picking it up from an already dusted insect as the stigma takes over the column once pollen has been shed). This aids in cross-pollination.
To the right is Stylidium turbinatum, showing the unique column in the resting position. Jostle the flower a bit and it springs forward very quickly, resetting in anywhere from minutes to half an hour, depending on temperature and a number of other factors.
The flowers are usually pretty small with the largest being a couple centimetres long. The plants themselves are small annual or perennial herbs with some 70% of all 300 species endemic to Western Australia. A handful of species are also native to southeastern Asia. The diversity within the genus in flower color and habit is astounding. At current count, the number of species in the genus makes Stylidium the fifth largest plant genus in Australia.
The genus is fairly old, being one of the collection from the 1770 voyage of James Cook and Joseph Banks to Botany Bay. Quite an interesting botanical history there, too, what with the genus epithet "Stylidium" having been used previously to describe a genus of ferns. The name was ultimately conserved after around a century of unsettled status and being moved around a bit.
In relation to wtf-ery, these plants have also recently been proven to be carnivorous. The small glands on and below the flower produce digestive enzymes, trap small insects, and are capable of absorbing the digested nutrients, much like the sundews (Drosera), though the tentacles are not mobile.
(Stylidium calcaratum below) So to review: 1) Awesome method of reproduction including super mobile column that attacks its pollinators. 2) Carnivorous! 3) Interesting botanical history, large genus, amazing diversity. Plus, virtually no one outside Australia ever really hears of these beauties and their interesting habits. A couple are widely available in cultivation and are easy to grow, so go on the look out for some new windowsill plants for your collection!
More images here and here.
Who said plants aren't motile?!