Calceolaria uniflora, or Darwin’s Slipper

Dear Readers, I spotted this photo on Facebook earlier this week, and it stopped me in my tracks – it looks for all the world like a gang of happy Muppets running down to the sea for a paddle. But, in fact, it’s a plant, and furthermore one that you might have had as a houseplant – I remember Calceolaria being very popular when I was growing up.

Calceolaria pot plant (Photo by Bernard Spragg. NZ from Christchurch, New Zealand, CC0, via Wikimedia Commons)

Otherwise known as lady’s purse or slipperwort, in the wild Calceolaria species can be found from Mexico to Patagonia. I inadvertently described the plant as an orchid in my Facebook post, but actually this is a member of the Scrophulariaceae or Figwort family, most of whom are very unobtrusive and are pollinated by various bees and hoverflies.

Scrophularia nodosa (Figwort)

The Darwin’s Slipper is a Patagonia specialist, and is pollinated by a bird called the Least Seedsnipe (you couldn’t make this up, clearly).

Least Seedsnipe (Thinocorus rumicivorus)

The Least Seedsnipe pecks at the white ‘lower lip’ of the Darwin’s Slipper, and while that’s happening, the plant is depositing pollen on the back of his or her head. What a splendid example of co-evolution this is! The bird is rewarded with rich, energy-giving nectar, and the plant gets to scatter its pollen as widely as the bird flies. What fascinates me is that this bird is not normally a nectar-feeder, but eats seeds, as its name suggests. This plant seems to have seduced the seedsnipe into changing its behaviour, something that occasionally happens with other species – the crown imperial, for example, is now sometimes pollinated by blue tits, who are normally insectivores.

Darwin’s Slipper, showing the white ‘pecking spot’ (Photo by By Michael Lejeune – Self-photographed, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=3133546)

I have always been fascinated by Patagonia, though it is a very, very long way away for a visit. Maybe I’ll just have to be content with looking at photos of these extraordinary plants.

Photo by By Thomas Mathis – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=1026481