Ultraviolet Flowers: Anemone ranunculoides

Anemone ranunculoides L.

Ranunculaceae

Anemone ranunculoides. Visible light

Visible light
Nikon D1H , UV-Nikkor 105 mm f/4.5, no flash

Anemone ranunculiodes. UV light

UV light
Nikon D1H , UV-Nikkor 105 mm f/4.5 @800 ISO, FF filter + CC20C, SB-140

Anemone ranunculoides. IR light

IR light
Nikon D1H , UV-Nikkor 105 mm f/4.5 @800 ISO, Wratten 89 B, SB-140 + Wratten 87

In Norway, the Yellow Anemone frequently co-occur with its close relative, Wood Anemone (Anemone nemorosa). However, in sharp contrast to the latter species, A. ranunculoides exhibits a pronounced UV signature. The anthers and stigmas reflect little UV to make a marked contrast to the outer area of the petals, which reflects strongly in UV. There are indications of secondary, less strong, UV markings in the lower half of the petals. Perhaps these are caused by UV-absorbing substances leached out from this particular flower, which was photographed in an old stage.

The huge differences in UV signature may help explain the rarity of naturally occuring hybrids between these two spring-flowering species. Pollinators would easily differentiate their flowers.

In common with A. nemorosa, the Yellow Anemone has quite strong reflectance in near-IR. Both species in fact are virtually indistinguishable as seen in IR.