Lousewort Anatomy

Day 305: The Louseworts are in their best bloom at various times over the summer, but it's rare to find examples of every species during a single hike because they don't all flower at once. On July 29, I posted a photo of Bracted Lousewort (Pedicularis bracteosa). Today, I bring you two more: Sickle-top Lousewort (P. racemosa, left) and Bird's-beak Pedicularis (P. ornithorhyncha, right). As you can see, there is quite a bit of variation in the shape of the corolla. Pedicularis is characterized by having a double-lipped flower. The upper lip forms a hood-like structure called a galea, and it is this feature which supplies many of the common names by which these plants are known. Sickle-top is obvious: its galea is the "curl in the middle of its forehead." Bird's-beak has a pointy nose. Coiled-beak is similar to Sickle-top, but its "beak" makes a tighter coil and its inflorescence is more densely packed, and favourite of all, Elephant-head has a long and unmistakable elephant's trunk. The unique shapes of these blossoms serve a purpose: they restrict access to the plants' reproductive parts to specific insects. Upon discovering such an exclusive restaurant, the insects seek out similar plants where they can dine at their leisure without being chased off by other insect species.