Merendera montana (L.) is a small, autumn-flowering plant, largely endemic to the Iberian Peninsula (Spain and Portugal). It is a member of the lily family (Liliaceae) and is widespread and common on heavily grazed grasslands, to which it is peculiarly adapted.  A high concentration of alkaloids – such as colchicine (1) – in the leaves ensures that it is avoided by herbivores, particularly sheep, during the winter period when the leaves are present.  The absence of leaves in the summer is probably another adaptation to avoid being consumed by grazing herbivores (1).  The bulbous plant then produces flowers from subterranean corms, in the autumn.  The flowers are particularly common on mountains and hillsides during the autumn months, such as October.  These photos of flowering Merendera montana were taken on 25th October (2013) in Galicia, Spain. 

The flowers have six petals and the stamens sport long yellow anthers.

Although Merendera montana flowers often occur in great profusion, it seems that the greatest densities of flowers are found in association with the mole-vole, or Mediterranean pine vole, (Microtus duodecimcostatus) (2).  Spanish researchers have discovered that the burrowing behaviour of these little rodents helps to disperse and propogate the plants, which return the favour by supplying the voles with an abundant food source, especially in the form of the underground corms (2).

1) Gomez et al. (2003).  Seasonal and spatial variations of alkaloids in Merendera montana in relation to chemical defense and pathology.  Journal of Chemical Ecology 29(5), 1117-1126.

2) Gomez-Garcia et al. (2004).  How does Merendera montana (L.) Lange (Liliaceae) benefit from being consumed by mole-voles?  Plant Ecology 172(2), 173-181.