Sunday, January 24, 2010
Pinguicula lusitanica - the Pale Butterwort
It's the dead of winter here in Connecticut, and Pinguicula lusitanica is looking its best. The biggest rosettes in the photo are only about 2 cm across, but that's about the maximum size for this annual to short-lived perennial carnivore from the western Mediterranean and Atlantic coast of Europe and northern Africa. The cultivation of this funny little butterwort perplexed me, until I realized that it is primarily winter-growing: the plants sulk in hot weather, and the seeds are reluctant to sprout in spring. It's now something of a weed in the carnivore collection out in the temperate greenhouse.
The leaves of Pinguicula lusitanica are distinctive, with edges curled over to the extent that they are almost tubular. The exposed part of the upper leaf surface is covered with hairs, and the sticky glandular trichomes are mostly hidden away under the curled margins (you can see some glandular surfaces exposed on the leaf at 7 o'clock on the rosette at left). Now I'm curious about how the plants trap insects in habitat: do the hairs guide prey into the overhanging part, where they are swamped in mucilage and digested? The traps seem almost pitcher plant-ish.