Virgin's shoes worn by chasmophyte gracing Roman aqueduct

Segovia has some beautiful stone walls, most obviously the massive Roman aqueduct towering over the city centre. On that, and other walls, you'll find the shoes of the virgin. Not the actual shoes of the, or a, actual virgin, but the Nine-leaved Sarcocapnos, aka Shoes of the Virgin.

It grows in some spectacular spots, such as this badge-like clump in the middle of the aqueduct as it sweeps through its highest reach. You expect a coat of arms but instead get a poppy with an odd-shaped flower. 

It is classified in the family Papaveraceae, along with the poppy, but so to is the often weedy Fumatory (Fumaria), which has a not dissimilar flower to our Sarcocapnos enneaphylla (in fact Swedish biologist Carl Linnaeus described it originally as Fumaria enneaphylla). The genus name means 'flesh smoke', perhaps a reference to the greyish leaf colour, the species name, nine-leaved.

The grey-green leaves are indeed divided into about nine segments, sometimes a few less, sometimes more. These leaves, and the plant itself, can be quite compact and tightly clumped. In other places, often shadier, the leaves are larger, less succulent and the plant more shaggy.

It's a native to Segovia, as well as other parts of central and eastern Spain, extending through the Pyrenees into other parts of south-western Europe and to North Africa. But that's it. By nature it is a chasmophyte, so before the Romans (and still today) it grew in non-human-created rock crevices.

According to University of British Columbia Botanical Garden Horticulturist, Jackie Chambers, Sarcocapnos enneaphylla has the Spanish common name Zapatitos de la Virgen (i.e. the Shoes of the Virgin). That Virgin is the biblical one, and the dainty flowers do look exquisite enough to be the shoes of some important person with a passion for odd footwear.

I gather the shoes can be there all year but most flowers are in spring, when I saw it (on an ASA Cultural Tour I led there in late May this year, and also on the same tour two years ago). The blotch on the flower is at first yellow, turning pink when the flower is no longer receptive to pollination. 

There are a couple of species in similar habitats in this part of the world but the number of leaf segments (between seven and eighteen, often nine) and some details of the flower anatomy are consistent with Sacrocapnos enneaphylla.

This is not the only chasmophyte to grace the walls and aqueducts of Segovia but in my mind it is the most intriguing and charming. The UK Royal Horticultural Society include this species in their list of potential garden plants for the UK - presumably for sheltered areas - and it would be a good one to try in Australia (although perhaps with the potential to spread to natural rock faces?).