Colour AND form variety of Anacamptis morio

Anacamptis morio
Oops, that’s a quite special Anacamptis morio which Norbert Griebl has found near Sittendorf, southwest of Vienna. In addition to the absence of anthocyanins (which happens quite often with this species) the lip has the same form as the sepals, with green veins. Here, not only the colour of the flower has changed, but also its morphological pattern.

Ophrys bertolonii “albiflora”

Ophrys bertolonii f. albiflora
With its deeply pink to purple colours in the sepals and petals and a deeply brown labellum, Ophrys bertolonii is one of the most intensely coloured Ophrys species. In Croatia, at the southern tip of Istria, Pavel Heger found a colour variety of Ophrys bertolonii – with an overall green appearance due to the remaining chlorophyll pigments. There are two characteristics which allow to address these plants as an “albiflora” form: 1) The typical marking at the lower end of the labellum is quite white. 2) The hairs at the edges of the labellum are white as well.

This rare plant demonstrates that “albiflora” forms of Ophrys species tend to retain chlorophyll – in contrast to the white flowering forms of Orchis or Anacamptis species. And there are distinct areas of the flower where chlorophyll is not retained as it is the case with the labellum marking of Ophrys bertolonii. Maybe these plants tend to be “white” in order to achieve a certain biological “albiflora” function – but the chlorophyll performance of the flower is still important and thus kept. Special thanks to Pavel for contributing to!

Rare albiflora form of Orchis spitzelii

In OrchideenJournal 3/2009, Josefa and Richard Thoma describe how they have found two white flowering plants of Orchis spitzelii for the first time in a region they have been visiting for about 20 years. This location in the Alps near Salzburg is the only place where Orchis spitzelii can be found in Austria.

In June 2009, the couple counted 17 plants when Josefa was surprised to find two white flowering Orchis spitzelii. “I didn’t trust my ears”, writes Richard Thoma describing his feelings when his wife exclaimed: “Two whites!” The author named the rare color variation “Orchis spitzelii f. albovirida” – with regard to the green perigone containing chlorophyll pigments.

“Why now, of all times?”, Thoma asks and is looking forward to next year when the want to see if the white forms appear again.

Maybe it’s more than just a “freak of nature” as Thoma is assuming. More substantial research is needed to see if there is a certain function which could explain why certain orchid species develop albiflora forms. Special thanks to Richard Thoma for contributing his photos of the white flowering Orchis spitzelii to

Flower colour matters

The females of this crab spider (Misumena vatia) can change their colour depending on the colour of the flower where they sit and wait for a prey. On a white flower they have a white body, on yellow flowers it is changed to an intense yellow (right, photo: Olaf Leillinger). Thus, the albiflora form of Dactylorhiza fuchsii (left, photo: Norbert Griebl) is quite a convenient place to hunt insects – the standard purple colour of this orchid would not fit her camouflage strategy. The spider changes its colour by secreting a yellow pigment into the outer cell layer of its body.While sitting on white flowers, this pigment is transported into lower layers. The colour change from white to yellow takes between 10 and 25 days, the reverse about six days.

Limodorum abortivum “albiflora” 

Limodorum abortivum: Albiflora form (left; Photo: N.Griebl) and common form (right)
Limodorum abortivum: Albiflora form (left; Photo: N.Griebl) and common form (right)

Limodorum abortivum is one of the rarest albiflora forms of orchids. Sometimes, literature is mentioning the existence of white flowering plants, e.g. Horst Kretzschmar states in his new “Die Orchideen Deutschlands und angrenzender Laender” (Wiebelsheim 2008), p.163: “In Southern Europe, there is a broad variation of flower colours, from white to purple to red, these colours have not been observed in Germany up to now, though.”  Norbert Griebl in Austria has sent me a photo of an albiflora form he found in northern Greece. He observed that the plant has a green stem and green sheathing leaves, “which prooves that Limodorum is not totally living saprophytic” (=myco-heterotrophic).

Compared with the violet stem colour of the regular form the green colour of the stem is indead striking. The existent chlorophyll is obviously covered by dominant anthocyanins. When these purple pigments are absent – as it is the case with the albiflora form – the green chlorophyll colour becomes clearly visible. A study published in 2006 (M. Girlanda, M. A. Selosse, D. Cafasso, F. Brilli, S. Delfine, R. Fabbian, S. Ghignone, P. Pinelli, R. Segreto, F. Loreto, S. Cozzolino and S. Perotto: Inefficient photosynthesis in the Mediterranean orchid Limodorum abortivum is mirrored by specific association to ectomycorrhizal Russulaceae. In: Molecular Ecology 15, 2006, S. 491-504) recognizes the existence of chlorophyll but stated that Limodorum abortivum’s photosynthesis “was found to be insufficient to compensate for respiration in adult plants”. It would be interesting to know how the albiflora orchid is behaving in this regard and if it is also dependent on nutrition by fungi.