Africa Calling

[nfoto]

As some of the UVP readers might have noticed, I have been travelling in South Africa for the last weeks. My aim there was to record as many UV signatures as possible to provide better insights into what variation of UV response can be expected within large families such as the Asteraceae.

 

Species identification is a major challenge on trips like this, in particular when you are encountering such an enormous floral diversity and a high percentage of localised, endemic species as well. Thus, getting the material ready for publication will take a significant time and demand efforts and co-operation with local botanists too.

 

Besides being - as usual - interested in "yellow" daisies and yellow flowers in general, I made a deliberate effect to document flowers of a red or purple colour. The reasons are two-fold: firstly, reddish flowers are not very common in the native flora of the Nordic countries, and secondly, so far any red or purple flowers done in UV mostly have had very drab UV appearance. I was curious to learn if the African flora showed similar traits.

 

Consider this a teaser for the forthcoming flower portraits. As it'll take time to put these into the formal UV Botanicals section, I aim to showcase some here without having the true taxonomical affiliation clarified.

 

 

Senecio and Felicia species make an intricate yellow-blue mosaic in UV. Nikon D3200 (built-in Baader U) and the 18 mm f/4 Nikkor AI. Nieuwoudtville on the Bokkenveld plains, Northern Cape Province.

[colinbm]

Thanks for the update Bjorn

I'll look forwards to your postings.

Col

[nfoto]

Another view of the colourful plains of the Bokkenveld, with an exuberance of annuals and geophytes, many of which are endemic to this small region.

 

The red-and-black 'trumpets' are Romulea sabulosa (Iridaceae), a highly endemic species occurring on just a few locations in the vicinity of Nieuwoudtville.

 

The visible scene as recorded by the D800 and a 24 mm f/3.5 PC-E Nikkor.

 

 

 

From the same standpoint, an overview in UV using the D3200 (built-in Baader U) and the 18 mm f/4 Nikkor AI.

 

[colinbm]

Thanks for sharing Bjorn,

These are some beautiful flowers in this field.

Col

[nfoto]

The first of the "yellow daisy bush" I encountered, showed the peculiar differentiation front-back of the ray flowers. A lot of the Composite Daisies show this trait.

 

Arctotis revoluta (Asteraceae), Cederberg Mountain Range.

 

Front view in UV, showing the distinct "bull's eye" enlarged by the black basal patches on the rays.

 

 

The rear view,

 

[DaveO]

Hi Bjorn,

I can see a fruitful collaboration on this sometime in the future as Australia was a distant neighbour of Africa when we were both part of Gondwanaland about 500 Mya (even before my time ) In the early days of settlement in Australia from 1788 onwards there was a lot of traffic from South Africa to support the starving colony in New South Wales so we unwittingly imported a vast array of what have become noxious weeds, such as Arctotheca calendula known here as Cape Weed. We also share some families https://en.wikipedia.org/wiki/Gondwana of plants from before our split about 184 Mya

 

Have fun,

 

Dave

[nfoto]

Another example of a "bi-colour" UV signature: Boslilie Cliva miniata Amaryllidaceae. Kirstenbosch, Western Cape.

 

 

(Nikon D3200 w/built-in Baader U, UV-Nikkor 105/4.5, SB-140)

[nfoto]

Disk florets tend to appear virtually black in most if not all Asteraceae species documented from Europe and North America. However, as already indicated by the Arctotis revoluta images shown in the first post, many of the South African daisies deviated by having the corolla of the disk florets rendered in bright (false) yellow.

 

Here is another sample to demonstrate this very unusual UV signature. Gorteria diffusa, Asteraceae (orange flowers with dark patches on the ligules, thought to be a mimicry feature to attract its specialised pollinator):

 

[OlDoinyo]

C. miniata is a popular potted plant in North America. I was unaware of its origins. The most common variety sold has orange-red blooms; it would be interesting indeed if it were as UV-pale as the specimens depicted here. What color were they to the naked eye?

[nfoto]

Orange-red.

[eseavey7]

I'm loving the colorful landscapes!

[Andrea B.]

Some intriguing and simply beautiful African flowers! Bjørn, it will be so nice to have these for our UVP collection. I hope the identification is going well.

 

Here in the US we do get some occasional African daisy-type flowers sold for bedding plants or as house plants. But to see them growing wild like that would be a real treat! I've seen that Clivia that Clark mentions at my local grocery store. But I have not purchased it to photograph because I don't really have a good place in this house to keep house plants.

[nfoto]

I'll post the species the identification of which I'm pretty secure in a few days. The others will probably be lumped together and presented as a whole.