“Orchideeën van de Benelux”

Karel Kreutz und Corinna Kreutz-Santen, Maastricht 8.3.2019

Turkey, Rhodes, Cyprus, Crimea – those are only some of the books about locations of orchids published by Karel Kreutz since 1998. Now he has presented a two-volume-opus about the orchids in Belgium, the Netherlands and Luxemburg: Orchideeën van de Benelux. The publication was accompanied by a symposium in Maastricht:

Among the lecturers was Daniel Tyteca of the Catholic University of Louvain, who presented the orchids of the Belgian regions Famenne and Calestienne. In the nature reserve of Lesse et Lomme alone, there are 31 species. Some of them, as Epipactis microphylla (2004), have only been proven a few years ago. Tyteca also pointed to colour variants of Anacamptis morio and Orchis mascula.

Those are shown in the book of Kreutz with special photos, as far as there are findings in the three Benelux countries. Albiflora forms are also shown of Dactylorhiza fuchsii, but interestingly not of Dactylorhiza maculata, Dactylorhiza majalis or Dactylorhiza incarnata – though there are albiflora forms of those species in other European regions. With Orchis militaris, Orchis simia and Orchis purpurea albiflora forms are also missing. Anacamptis pyramidalis is shown with a picture of an albiflora form of var. dunensis, which has been described by Londo, Kreutz and Sings in 2016. A hypochrome form of Ophrys apifera is also shown.

With regard to taxonomy Karel Kreutz is following the genus system of Daniel Tyteca and Erich Klein presented in 2008. Therefore Anacamptis morio is named Herorchis morio, Neotinea ustulata is Odontorchis ustulata. And Anacamptis laxiflora is introduced as Paludorchis laxiflora. But Kreutz is holding on to Aceras anthrophora und Listera ovata. The author concedes: Over taxonomie kan men sterk van mening verschillen – when it comes to taxonomy there are big differences of opinions. Zo is het onmogelijk om in dit werk een taxonomische indeling te hanteren, die voor iedereen aanvaardbaar is – therefore its not possible to present a classification which could be accepted by everybody. sei eine für alle akzeptable Klassifizierung nicht möglich. At least it would be desirable if the register at the end would also include the names which are used beyond the system of Tyteca & Klein.

In his opus Orchids of the Crimea, published together with Alexander Fateryga and Sergej Ivanov in 2018, Kreutz still followed the taxonomy which was developed by Richard Bateman, Alec Pridgeon und Marc Chase in 1997. The author explains the change to the system von Tyteca and Klein with their more recent genetical studies – although the conclusions are still controversial.

Next year Karel Kreutz will present a field guide Orchids of Europe, North Africa and the Middle East. Later on there is to follow a complete overview of the European orchids in ten volumes – expected for 2021/22, as it was announced in Maastricht. Since Pierre Delforge is following the taxonomic system of Tyteca and Klein since the 4. edition of his opus Orchidées d’Europe (2016), this taxonomy might achieve a broader acceptance in future.

Orchid conference in Neumuehl: Rescue mission in Switzerland

An unusual rescue mission in the canton Zurich was subject of the 2018 orchids conference in Kehl-Neumuehl, Germany. In this Swiss region, nutrient-poor grassland and bright forests have been dramatically reduced, René Gaemperle explained. Reasons are – as in other regions – the over fertilization of the intense agriculture and the increased building activity: “Where the hills are most beautiful, country residences are built”, Gaemperle said.

In order to strengthen weak populations like Ophrys araneola, Gaemperle cooperated with officials and organized manual pollination, collection of seeds, mixture of seeds with river sand and sowing. If the appropriate symbiosis fungus is in soil, this method works rather soon, explained Gaemperle. The time from sowing to first flowering is just three to six years.

He chose a different method with Anacamptis coriophora: Seed capsules from the Lake constance habitat Wollmatinger Ried have been sent to an expert for in vitro culture in Sweden. The young plants have then been planted at seven places in canton Zurich, overall 525 plants until 2015. In this year 56 of those plants have flowered, Gaemperle told. When species are threatened by extinction, such methods are the only way to save them. “If we don’t act now, they will vanish forever.”

Threatened orchid species are also an issue for Peter Steinfeld who lectured about the nature reservate Bliesgau in the German state of Saarland. Steinfeld has been observing the changes of the regional flora for 35 years. According to him, Cephalanthera rubra is threatened by extinction in Saarland – he found the last flowering plants  in Bliesgau about 20 years ago. Heavily decreasing is also Dactylorhiza viridis. But Limodorum abortivum is expanding, probably coming from the French region of Lorraine. The same case is with Ophrys sphegodes and Orchis simia. As another “profiteer of climate change” Steinfeld named Himantoglossum hircinum. Climate change was also the subject of my lecture with impressions of this summer on Gotland, Sweden. Jean-Marc Haas also reported about dried out places in Uzbekistan.

At the conference with more than 60 participants from four countries, which was organized by Harald Baumgartner and Hubert Heitz, Helmuth Zelesny lectured about a field trip to the Golzentipp mountain in Eastern Tyrol, with colour variants of Nigritella rhellicani in white, yellow and carmine. In this region at the edges of the Lienz Dolomites Gymnadenia conopsea is also quite often white-flowered. Hybrids of both species display a big variety of forms. Not so common is the hybrid of Gymnadenia conopsea with Pseudorchis albida. Nigritella rubra is flowering on lime stone. The variety of the orchid flora on this Alpine meadows has also been described by Norbert Griebl in his paper published by AHO-Berichte.

Helmut Presser lectured about new taxons related to Ophrys holoserica and Ophrys scolopax in France as there are Ophrys demangei and Ophrys quercophila, the oak loving Ophrys. Hartmut Moeller again showed impressive photos of pollinators, this time he observed Epipactis palustris with potter wasps, bumblebees and beetles.

Trip reports and expert debates

After 21 years, the Orchid Conference of Sundheim, Germany, has found a new place: About 50 participants met in Kehl-Neumuehl in the beginning of October, in a Protestant community centre, only a few kilometres away from the traditional meeting place in the old “Stierstall”. The history of the conference has been described by Werner Hahn in the latest edition of Berichte aus den Arbeitskreisen Heimische Orchideen (Jg. 34, Heft 1, 2017, S.234-237).

This year, the program focused on travelling reports from Iran (Jean-Marc Haas), Croatia/Greece (Stefan Hertel) and Israel (Helmut Presser). Jean-Marc showed findings of Ophrys zagrica in an altitude of 2300 metres, Ophrys khuzestanica and Ophrys strausii as well as Tulipa stapfys in the midst of dry pebble, Fritillaria imperialis or Iris acutiloba subsp. longipetalis. Stefan followed the transition of Ophrys incubacea to Ophrys mammosa and presented Ophrys cephalonica from the island Kephalonica with its long narrow sepals. In the beginning of March, Helmut has explored Mount Karmel and Mount Meron. Among the species which grow there are Ophrys carmelii and Orchis galilaea.

Typical for the delight of orchid scientists in disputes was a discussion after a lecture of Wolfgang Wucherpfennig. He stressed his criticism on the taxon Ophrys lutea var. subfusca for an orchid flowering in Northern Africa. The description of Heinrich Gustav Reichenbach in 1851 – along with two not so significant sketches – had resulted in the fact, “that the name subfusca has been used for many different species in the following years”. The situation which has been developed is quite disturbing. Wucherpfennig pleaded anew: “The name subfusca should not be used anymore but should be viewed as a nomen dubium.” But Karel Kreutz pointed out that a herbar finding in the Reichenbach collection which is indicated as “Ophrys fusca” should be viewed as the holotype of Ophrys lutea var. subfusca. And he stated that he has found according plants in Algeria – documented in his paper C.A.J. Kreutz/L.Lewis: Typification of Ophrys lutea var. subfusca Rchb. f., invalidity of the name Ophrys murbeckii H.Fleischmann. In: Journal Europäischer Orchideen Vol. 46, 1/2014.

The participants persued their discussion for a while – without answering the question why this detail of science history should be so relevant. In the long term, questions of the preservation of orchid species are much more important than any taxonomic debates.

orchids conference in Sundheim 2: Floral photosynthesis

Why are Ophrys flowers with a defect in pigment production yellowish-greenish and not white as it’s the case with Orchis, Dactylorhiza or other genera? I’ve tried to give an answer to this question at the orchids conference in Sundheim (Germany), in a lecture titled The Ophrys flower – more than an invitation to pseudo copulation.

Ophrys holoserica
Ophrys holoserica

My assumption: The lips of all Ophrys flowers are green – but in most cases we can’t see it, because the chlorophyll in the lips is covered by anthocyanins. Only if the production of anthocyanins is disturbed, the chlorophyll in the Ophrys lip is visible, often together with yellow pigments. Only the marking of the labellum is free of those pigments, it appears in the case of a defect in Anthocyanin production as white. But even in the lower segments of the bluishly shining marking of Ophrys speculum researchers have showed the existence of chloroplasts, of cell plastids with chlorophyll. The bluish color comes from the vacuoles of the epidermis which are filled with cyanidin pigments, while the brown rest of the labellum in addition contains delphinidin, quercetin and anthocyanin pigments.

The Ophrys forms without anthocyanins cannot be termed as white-flowered or albiflora. It makes more sense to call them hypochromic in the meaning of a underdeveloped production of color pigments.

Those forms have been found with more than 20 Ophrys species.

Near the Swiss town of Basel there is a whole population of Ophrys apifera plants without anthocyanins in the labellum. Those plants have been described as Ophrys apifera var. basiliensis.

Anthocyanins also acts as a sun protection. They have the ability to absorb damaging light energy as UV UV radiation. The water-soluble anthocyanin pigments are in the vacuoles of the plant cell, which also contain water and nutrients. This protective function of the pigment is especially important for plants in Southern Europe.

In general, the petals of flowering plants don’t have chlorophyll. The tissue of their flowers and fruits don’t have chloroplasts (those cell parts which contain chlorophyll and therefore are green), but chromoplasts. Those don’t have chlorophyll, but for example carotenoids: yellow, orange or red color pigments.

Only in the early bud stadium some flower plants still have some amounts of chloroplasts – later, those develop to chromoplasts or colorless leucoplasts with the function to store proteins or starch – this process has been explored in an interesting report by Kevin Pyke and Anton Page. The same transformation can be observed when tomatoes are ripening – the fruit is green at first, with many chloroplasts and chlorophyll, which later change to chromoplasts with the red lycopene pigment.

The cells of green leaves have about 20 to 50 chloroplasts with chlorophyll. They are filled with stroma, which also contains the enzyme Ribulose-Bisphosphat-Carboxylase/Oxygenase (RuBisCo). Together with water and sun light, this enzyme has a decisive role in transforming carbon dioxide in glucose: from CO2 and H2O to C6H12O6.

Studies have demonstrated that orchids of sunny meadows in the Mediterranean can be viewed as mycoheterotrophic: They get at least a part of their nutrients from fungi. Since fungi can dissolve the nitrogen (which is important to produce enzymes) of the soil much better than higher developed plants, mycoheterotrophic orchids have a better nitrogen supply than other plants without this special relationship. The different orchid species have different relationships with fungi, but many orchids rely on fungi of the genus Tulasnella.

Additionally, Ophrys orchids make use of the fact, that they have chloroplasts in their flower tissue, so photosynthesis becomes possible in the flower. Some Ophrys species also have intense green petals – in contrast to the labellum there are no anthocyanins in these petals which would otherwise cover the chlorophyll.

It can be assumed that Ophrys flowers make use of the Crassulacean Acid Metabolism (CAM). This mechanism of photosynthesis, named after the family of the Crassulaceae, is especially adapted to hot and dry places.

The advantage of this CAM photosynthesis compared with the standard C3 photosynthesis: The plant cells receive carbon dioxide at night. Then, the stomata of the plant tissue are open. In the daily heat they can be closed, so the plant is protected from dehydration. The CO2 received by night is stored in the vacuoles of the cell in form of malic acid. By day, it will be transformed to carbon dioxide and oxygen by the help of light energy. The CAM photosynthesis only needs less than a fifth of the water amount which is normally necessary in the case of C3 photosynthesis. Therefore, the plant can survive in dry times and is protected against lack of water.


Einfaches RGB

There are also plants with a facultative CAM photosynthesis: the water saving mode will only be used in dry summer times. In spring, the budding plants still use the C3 photosynthesis. While CAM has the advantage of a lesser water consumption it also has a big disadvantage: The production of biomass is quite lower. CAM plants grow much slower than C3 plants.

Most orchids with thin leaves use a C3 photosynthesis. Among them are the genera Orchis, Dactylorhiza, Anacamptis and Neotinea. Those with thick leaves can master CAM photosynthesis, for example the tropical genera Phalaenopsis, Cymbidium or Cattleya.

Since CAM plants have to store CO2 by night in order to enable the daily photosynthesis, they have enlarged vacuoles. Thick leaves can store more organic acid which conserves CO2 in night time. It may well be that this is also the case with the floral photosynthesis of Ophrys. One clear sign is the thick Ophrys labellum – the form which also has its special function to imitate female pollinators to induce pseudo copulation. The often low height of Ophrys is an additional sign that those species are at least facultative CAM plants, since there is less biomass produced.

An advantage of the floral photosynthesis is the ideal position of flowers to the sun light. The higher amount of light energy absorbed enables a higher capacity to store CO2. Though there is no detailed research yet, there are many signs that especially the Mediterranean Ophrys master a floral photosynthesis. The CAM metabolism enables them to survive in dry climates, on rock grounds, with early withering leaves. The evolution of the Ophrys labellum fulfilled two functions: the adaption to pollinators and the ability of floral photosynthesis.

A cycle of vegetation becomes visible which determines the life of Ophrys. There are four phases which are adapted to specific environment conditions and biological demands:


The seedling is developing under conditions of a mycoheterotrophic supply with nutrients. Developing the first leaves, photosynthesis becomes possible. It can be assumed that the C3 mechanism of photosynthesis is still dominant, since temperatures are moderate in spring and there is enough water. And the plant needs to grow quickly, to build up biomass. Here the C3 photosynthesis has a clear advantage.

The budding plant is still growing, the leaves reach their optimal capacity for C3 photosynthesis.

Beginning with flowering the leaves begin to wither. So the flower starts its additional CAM photosynthesis and secures a sufficient supply with nutrients even under conditions of increasing heat and drought.

When the fruits ripe there is again a phase when biomass has to be added. But the capacity of photosynthesis is decreasing when the flower is withering. Now the role of the mycoheterotrophic supply with nutrients might become more important again.

orchids conference in Sundheim 1: From Odenwald to Iran

The 20th conference of orchid experts in Kehl-Sundheim invited its participants to a long journey: The lectures had a broad range from the German regions of Odenwald and the upper valley of the Fils to Austria and Iran.

Orchideentagung Sundheim
Orchids Conference Sundheim

The trip report form Iran opened the conference: Jean-Marc Haas showed impressive pictures of orchids, tulips and Fritillaria. Markus Sonnberger from Heiligkreuzsteinach presented a botanical profile of the Odenwald. Among orchids, Himantoglossum hircinum and Epipactis helleborine are increasingly present, while other species are declining: Dactylorhiza fuchsii, Dactylorhiza majalis and Orchis mascula. In this region there are also growing Cephalanthera longifolia, Orchis militaris, Neottia ovata, Neotinea ustulata and Platanthera bifolia. Markus Sonnberger also showed botanical rarities of the region as Buxbaumia viridis or Stellaria neglecta.

H. Moeller showed impressive pictures of potential pollinators of Neottia ovata, among them wasps of different sizes. He observed them at short distance with his Lumix compact camera.

Norbert Griebl lectured about the “finest orchid regions of Austria” some albiflora forms as Gymnadenia conopsea in white and greenish, at the Golzentipp in the Gailtal Alps, or a white flowering Anacamptis coriophora in the valley of Lobau.

Prof. Hannes Paulus from Vienna presented the latest results of his research about the pseudo copulation of Ophrys species. He criticized a “unprecise use of the subspecies term in botany, that’s a big mess”. From his view it’s not correct to describe Ophrys illyrica und Ophrys tommasinii as subspecies of Ophrys sphegodes – “both have a different size and different pollinators, they are different species”.

Helmut Zelesny viewed white flowering forms of Orchis militaris, Gymnadenia conopsea and Neottia nidus-avis in the upper valley of the Fils near Unterboehringen as “freaks of nature, without scientific value”. But this does not explain why white flowering forms of some species and in some regions are more common than in other cases. Zelesny also showed the photo of a hybrid of a white flowering Orchis mascula and Orchis pallens.

Sundheim Orchid Conference 2012

Sundheimer Orchideenkonferenz
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.

Wolfgang EccariusIn 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 Sebastian Sczepanski as Dactylorhiza kafiriana subsp. baumgartneriana, is named after Harald Baumgartner, the organiser of the Sundheim Orchid Conference.

Lecturing about albiflora orchids in Koblenz

Invited by the Arbeitskreis Heimische Orchideen (AHO) Rhineland-Palatinate I’ve presented some thoughts about albiflora orchids at a meeting in Koblenz. After introducing the basics of the bio-chemistry and genetics of flower colours I pointed to the striking differences in the frequency of albiflora forms with certain orchid species. With frequencies of more than 0.1 per cent one might assume that albiflora forms are not just the result of spontaneous mutations but may indicate a certain evolutionary process. With regard to Dactylorhiza fuchsii there is reason to believe that there are ecological pressures favouring albiflora forms – a hypothesis, which will be elaborated in an upcoming article in AHO’s journal “Berichte aus den Arbeitskreisen Heimische Orchideen”.

Exhibition in Frankfurt demonstrates color in nature

“The palette of colors in nature is almost infinite”, says the botanist Hilke Steinecke of the Palmengarten in Frankfurt. There, this palette is displayed in an exhibition which can be visited until November 1st. The exhibition also explains the role of pigments in the colors of flowers and how fertilizing insects see colors.

An interesting demonstration shows the acid sensitivity of anthocyanins. When a drip of vinegar is placed on the violet flower of  Ipomoea, its color changes to pink. “In an acid milieu many anthocyanins are rose-pink, in an alkaline milieu blue”, as it is stated in the catalogue. This phenomenon could also explain the color variations of Nigritella nigra ssp. rhellicani in the Dolomite Alps – these occur especially in a region with rather acid soil.