Two white flowered forms of Orchis are presented by Norbert Griebl in the latest edition of “Berichte aus den Arbeitskreisen Heimische Orchideen” (29/2012, 2, p.94-110). The contribution gives an overview of the seven Orchis species in Austria and shows their distribution maps. About Orchis spitzeli he notes: “In some years white or whitish plants appear at the location in Salzburg.” The paper has a photo of a second white-flowered plant, an Orchis mascula subsp. speciosa fo. albiflora. In the same edition of the “Berichte”, Adolf Riechelmann decribes his field trip to Ibiza and mentions an apochrome specimen of Ophrys dyris, found at the southern tip of the Mediterranean island. But the main article of the edition is contributed by Werner Hahn: In the footsteps of Christian von Steven. Searching orchids and pollinators in the Crimean mountains 2011 and 2012 – an exciting study of the orchid flora of the peninsula and as well as of a special chapter of the history of botany.
On the occasion of a visit to Prague I looked up some specimens at the Charles University Herbarium (PRC). In order to help a friend, I searched for the holotype of a plant which was described by the Bohemian botanist Ignaz Friedrich Tausch as Ophrys purpurea (Flora; oder, (allgemeine) botanische Zeitung. Regensburg, Jena 1831) – now regarded as a synonym of Ophrys apifera or as Ophrys apifera var. tilaventina. The holotype was said to be in the herbarium in Prague, so I searched several packages of Ophrys specimen there, with the much appreciated help of PRC’s curator Jan Stepánek.
The holotype of Ophrys purpurea was not there, but I found an interesting specimen collected by the French botanist Jean Michel Gandoger (1850-1926):
The description carries the information that Gandoger collected this plant in 1879 near Algier as Ophrys apifera f. elata, formerly described by Tausch as Ophrys purpurea:
At the end of my visit I searched a further package of specimens with dried Orchis plants – hoping to find a albiflora specimen. Instead I detected a specimen collected by Tausch as Jan Stepánek confirmed by examining the hand-written label with the nomber “1470″ attached to the stipe of the plant:
A further label written by an unknown person has the information: “Orchis mascula L. vom berge Rhadisken bei Leitmeritz” – this information matches the catalogue of “Fundorte der Flora Boehmens nach weiland Professor Ignaz Friedrich Tausch’s Herbarium Florae Bohemicae alphabetisch geordnet von Johann Ott”, published 1859 in Prague:
So who was this Ignaz Friedrich Tausch? The Bohemian botanist was born on January 29th, 1793, in Udrči near Karlovy Vary. After his thesis about “De inflorescentia” (1835) he was director of the botanical garden of duke Canal de Malabaillas in Prague. He studied a broad spectre of plants and published “Bemerkungen über einige Arten der Gattung Paeonia” (1828) as well as his Flora Bohemiae (1831). Tausch was all his life rather poor, Stepánek told me. So he sold dried plants ot different herbariums. Tausch died on 8th September 1848 in Prague.
Two great publication projects about European orchids are being prepared which will meet high expectations. At the 16th Orchid Conference in Sundheim (near Kehl, Southwest Germany), Wolfgang Eccarius offered a first look into his project of a monography about the genus Dactylorhiza – the planned publication year will be 2015. Among the about 50 participants of the conference, coming from Germany, Switzerland, France and the Netherlands, was Karel Kreutz who is working on an opus of 6 to 7 volumes about all the orchids in Europe, which is expected to be published probanly in 2016.
At the beginning of the meeting, Helmut Baumann showed a series of impressive videos showing pollinators of different orchid species. Helmut Presser presented photos of his latest Greece journey, Peter Goelz showed pictures taken at two different locations of Ophrys kreutzii in Turkey and the Essink couple shared impressions from Rhodos.
In my contribution about “Colour polymorphism with Dactylorhiza – Evolution as a continuing process” I presented my studies about Dactylorhiza fuchsii and the calcifugiens location in Northern Danmark. After a partly controversial debate, Wolfgang Eccarius talked about the specific difficulties of his Dactylorhiza project. The common genetical methods to differentiate between species, such as the construction of cladograms by means of an analysis of the DNA’s ITS regions, may be used only with great caution in this case, he said. “This doesn’t function at all”, if a species has developed from two species. Therefore, he intends to base his book of about 600 pages on a rather broad concept of species. At the beginning, there was a comprehensive study of literature, including about 1100 protologues (original decriptions). “This fact alone implies that the nomenclature of this genus will be a giant challenge”, Eccarius said. In order to concentrate on the essentials, he only wants to present species and subspecies in length, without ignoring varieties. “I succeeded in looking into all typesheets”, Eccarius said – with one exception: “I’m still missing the typesheet of Dactylorhiza incarnata subsp. baumgartneriana. The typesheet cannot be found in Stuttgart, where it is said to be.” This subspecies, described by B. and H. Baumann, R. Lorenz and R. Peter in 2003, later described by Kreutz und Stefan Sczepanski as Dactylorhiza kafiriana subsp. baumgartneriana, is named after Harald Baumgartner, the organiser of the Sundheim Orchid Conference.
In a paper published in the latest edition of the Journal Europaeischer Orchideen (vol 44, 2/2012, p. 421-426), Wolfgang Wucherpfennig reviews the recent publications about the phylogenetic tree of the Monocotyledonae. He points out that the Orchidaeceae are between 104 and 120 million years old (A in the phylogenetic tree) and that the first orchids have been grazed by dinosaurs. So, orchids are in fact older than their relatives in the Amaryllis family (Amaryllidaceae) or the Asparagus family (Asparagaceae). Only the differentiation of the genera of orchids (B in the phylogenetic tree) has a more recent age and happened between 76 and 84 million years ago. Wucherpfennig concludes: “So, orchids are not a young plant family at all, they have a dignified age. But very old families also have small children which are enterprising and adventurous such as Ophrys and Dactylorhiza.”
Thanks to all the contributions to this project website albiflora.eu I’ve compiled a first paper about the white-coloured forms of orchids, published in Berichte aus den Arbeitskreisen Heimische Orchideen (1/2012, p. 141-170). Following a short overview about taxonomic aspects the relationship of flower colour and fertilizers are discussed. The main part considers the differences of albiflora forms with particular genera of orchids. The paper finishes with a discussion of high frequencies of albiflora forms with Dactylorhiza fuchsii in Western Ireland and certain regions in Germany. Where does random mutation ends and where begins an evolutionary process? One possible scenario might be that nectar deceptive orchids flowering earlier than Dactylorhiza fuchsii – as there are Orchis mascula or Dactylorhiza majalis – impart fertilizing insects the experience that flowers with a certain form and a purple colour don’t grant them any nectar. Thus, a colour change to white might be an advantage. The German language paper can be downloaded here.
Most orchid species don’t like acid boglands – but there are two rare exceptions: One is geographically widely distributed from Belgium to Northwestern Germany and Scandinavia and is mostly addressed as Dactylorhiza sphagnicola. The other grows only in the Danish region of Thy: Just a few hundred meters behind the coastline of the North Sea there is a population of white-flowered orchids which have been described by Henrik Ærenlund Pedersen as Dactylorhiza majalis subsp. calcifugiens (in: Nordic Journal of Botany, 2004). In 2007, Sebastian Sczepanski and Karel Kreutz argued it would be more appropriate to regard these plants as a subspecies to Dactylorhiza sphagnicola – while Pedersen und Mikael Hedrén are viewing sphagnicola only as another subspecies of Dactylorhiza majalis. Apart from colour, the morphological differences of the single flowers of Dactylorhiza majalis subsp. majalis (left), calcifugiens (middle) and sphagnicola (right) are difficult to discern:
src="http://www.albiflora.eu/images/science/majalis_calcifugiens_sphagnicola_sm.png" alt="Dactylorhiza" />The spur of Dactylorhiza sphagnicola is a bit longer than that of D. majalis subsp. calcifugiens. And the leaves of the latter are spreaded in a broader angle than those of D. sphagnicola:
The single flowers don’t show any hue of purple, even the pollinaria lack Anthocyanin. There is rather some yellowish hue in the center of the flower, slightly reminding of Dactylorhiza incarnata subsp. ochroleuca. In contrast to other populations of albiflora forms, e.g. with Dactylorhiza fuchsii, there are no gradual differences in the loss of colour pigments – all the plants are consistent in the white colour of their flowers.
Visiting the region, I found calcifugiens at two places, one near the small fisher village of Lild Strand with only three plants, the other further to the south at a bog called Nissekaer with about 150 plants. Surrounded by dunes this place is a natural depression (danish: “kaer”) with a length of about 1500 and a width of about 250 meters:
In mid-June the orchids are just in the beginning of flowering. Most Dactylorhiza majalis subsp. calcifugiens are growing at the edges of the wet places, not in the midst of them as it is the case with Dactylorhiza sphagnicola in the Venn moors in Belgium. And the calcifugiens plants are quite smaller, reaching just a height of up to 31 cm. Neighbouring plants are Sphagnum palustre, Equisetum fluviatile; Eriophorum angustifolium, Menyanthes trifoliata, Vaccinium oxycoccus, Calluna vulgaris, Trientalis europaea and even Drosera rotundifolia – most of those plants are clear indicators of acid soil. Among the shrubs there is the dominant Myrica gale, which is used by the brewery of the near-by town Thisted.
Some calcifugiens plants show a broader labellum, indicating a possible hybrid influence of Dactylorhiza maculata – similar to the sphagnicola plants of the Venn region.
Among all the white-flowered orchids in the Nissekaer bogland I found two purple-flowered plants which might be a hybrid of Dactylorhiza majalis subsp. calcifugiens and Dactylorhiza maculata (left) and a Dactylorhiza maculata still in buds (right):
As a visiting and possibly pollinating insect of Dactylorhiza majalis subsp. calcifugiens there was a species of the genus Syrphida – as I’ve seen also with Dactylorhiza sphagnicola in the Venn moor (left)
Orchid locations are constantly changing: On a meadow last visited in 2010, the number of Dactylorhiza fuchsii has been quite smaller this year. Now, there have been more Dactylorhiza majalis then before – and several hybrids of both species. These may have quite different forms: either short plants with the broad leaves of majalis (above) and brighter, fuchsii-like flowers with a broad labellum – or more elongated, with narrow leaves and purple flowers with a slightly broader labellum (down).
The Dactylorhiza fuchsii on this meadow which has both wet and dry areas are still quite bright, but most retain some purplish hue, at least in the pattern of the labellum. This time, an albiflora form of Dactylorhiza majalis was also flowering.
It is well studied that Cephalanthera damasonium belongs to those orchids which can live without chlorophyllum – together with other species of the tribe of Neottieae or the genus Epipactis. While exploring a mixed forest near Lahnstein (Rhineland-Palatinate) together with Ingo Beller of the Arbeitskreis Heimische Orchideen (AHO) Rheinland-Pfalz, we found a group of three albino plants in addition to three green-leafed Cephalanthera damasonium. Of the apochromic plants one has two flowers, one only one flower and one has no flower. Those albino plants receive their organic carbon with the help of fungi. A study of V. Tranchida-Lombardo, M. Roy, E. Bugot, G. Santoro, Ü.Püttsepp, M. Selosse and S. Cozzolino, published in 2010 in Plant Biology suggests that the albino Cephalanthera damasonium may be viewed as “an intermediate step in the evolutionary emergence of mycoheterotrophy”, or of the ability to be nourished both by fungi and photosynthesis. By means of genetic analyses the authors declare: “Albinos could be either permanent mutants, as suggested by phenotype stability over the years, or transitory phenotypic stages, in which genes involved in the photosynthetic pathway can switch off depending on micro-environmental conditions (e.g., the amount of C resources provided by the nearby fungal mycelia or tree roots) that prevent greening.”
In addition to the Irish region of The Burren and the Hesse location of Biebergemuend there is a further location where Dactylorhiza fuchsii tends to white-flowered forms in big numbers: In a birch grove near the village of Wolken in the upper Moselle valley there are several hundred plants with a clear trend to bright and white flowers. A count of a random sample resulted in 13 per cent of white flowers without any markings on the labellum. Further 38 per cent of the plants have a white base colour with pink marks. The differences in flower colours correspond with the results found in the other two regions and are even a little bit more accentuated. These results may give further evidence to the assumption that Dactylorhiza fuchsii is in the midst of an evolutionary process which also changes the phenotype of the species.
Percentages of flower colours in different locations
The following tableau shows the wide range of fuchsii flowers found on that location. The brightest forms also lack the Anthocyanine pigments in the pollinaria as the lowest row of examples and the following macro photo demonstrate.
The only other orchids in the forest are Platanthera chlorantha and an Epipactis spec. – while in the other two locations with abundant albiflora forms of Dactylorhiza fuchsii there are also the earlier flowering Orchis mascula (Burren) and Dactylorhiza majalis (Biebergemuend), both flowering in pink and both – as well as Dactylorhiza fuchsii – trying to attract pollinators with nectar deception. Among other plants in the birch forest, a former gravel-pit and now a nature reserve called “Kuhstiebel”, are Orthilia secunda, Fragaria vesca and Tussilago farfara. But the dominating plant there as well as in a nearby marsh area is Dactylorhiza fuchsii with mostly spotted leaves – even in the case of the white-flowered plants:
Misumena vatia, a crab spider has developed a special relationship with orchids. Sitting on an albiflora form of Dactylorhiza fuchsii it wears its white body, as Norbert Griebl has observed. Now I’ve watched her in Thuringia on Cypripedium calceolus in its yellow form – a perfect mimicry. The spider makes use of the fact that the slipper-shaped pouch of the plant traps small insects in order to ensure its fertilization – while is spider is only interested in food.
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.
The Cypripedium calceolus in Thuringia show almost none varieties in terms of flower colours. Among more than 1000 plants I’ve found one with reduced anthocyanin pigments in sepals and petals which could be addressed as Cypripedium calceolus forma citrinum.