Orchis pauciflora with reduced carotenoid pigments

Orchis pauciflora – photo: Bariša Ilić 

Among a population of about one thousand Orchis pauciflora in Southern Croatia, Bariša Ilić from Metković found 8 plants with almost white flowers. Their bright lips are contrasted with its reddish spots. This is the first time that he observed those special forms at a location near the town of Ston, in Dubrovnik-Neretva county. Bariša Ilić is an ornithologist, who fell in love with native orchids five years ago, as he explains.

Orchis pauciflora – photo: Bariša Ilić 

The flowers of Orchis pauciflora have a strong yellow color. They contain high concentrations of carotenoids – pigments who create the yellow flower color with many plants. While anthocyanines – which create red, purplish or brownish flower colors – are water soluble, carotenoids are lipid soluble (like chlorophyll). Since anthocyanines are produced in a complex process of biosynthesis with the participation of more than five enzymes, it is more likely that there will be a loss of anthocyanines than it might be in the case of carotenoids. This might explain why Orchis pauciflora with whitish instead of yellow flowers are extremely rare – and even in these findings, the plants seem to have retained a last rest of yellow color in the center of the labellum.

This impression of a gradual loss of carotenoid pigments corresponds with an interesting study of the Italian botanist Alessia Luca. She showed how the concentration of carotenoids is changing in the case of hybrids between Orchis pauciflora and Orchis mascula. Her thesis at the Università della Calabria includes the measuring of anthocyanin and carotenoid concentrations in the labellum of the hybrid plants, Orchis x colemanii. The results show that concentration von carotenoids is gradually decreasing in the hybrids: “O. xcolemanii showed a continuous flower color variation (Figure. 13) ranging from red-purple flowers of O. mascula to yellow flowers of O. pauciflora.” (Alessia Luca: Evolutive significance of hybridization in Mediterranean deceptive orchids, p. 42)

Alessia Luca: Evolutive significance of hybridization in Mediterranean deceptive orchids, p. 43

Comeback for the white Orchis militaris

In 2006, I first observed a white-flowered Orchis militaris in a grassland area near Frankfurt. It re-appeared in five following years. Last time I have seen it in 2010. But then it disappeared, no sign of an albiflora form among the more than 100 Orchis militaris plants of these meadows. Until this year, when it flowered again in a distance of about five meters from the first plant.

Orchis militaris f. albiflora

After the first third of May the inflorescence was already about to fade. The orchid expert Werner Hahn told me that in the 1980s the flowering in this habitat started only at about mid May – clearly a consequence of climate change in the last more than 30 years.

But the question remains: What is the reason that the albiflora form has a comeback after ten years? Seeds of the white-flowered plant might have been spread on this meadow. The color of flowers is a factor which is inherited by dominant alleles. But there still remains the small chance that the genetic characteristics of white flower will be expressed by the new plant in a population of more than 100 plants of the standard color.

Orchis militaris f. albiflora

The probability of albiflora forms among populations of Orchis militaris is about 1/1000, I guess. In the Middle Rhine Valley this beautiful plant is just flowering:

Orchis militaris f. albiflora – photo: Werner Hahn

Colony of Orchis quadripunctata f. albiflora

Orchis quadripunctata – photo: Robert Crnković

Orchis quadripunctata is a more than common species in mid Dalmatia. For more than ten years, Robert Crnković is looking for white, albiflora examples among numerous local populations  in the region of Trogir. In the beginning of May, he writes, I literately “stepped on” a small group of about 50 normal, pinkish plants, and, within the group, 14 snowy white ones. Such a great colony of albiflora forms can’t be explained by spontaneous mutations of individual plants. It seems that the white-flowered forms have propagated themselves in a quite unusual way.

Orchis quadripunctata – photo: Robert Crnković

In some cases of white-flowered Orchis albiflora the two or four small points on the base of the labellum – to which the name of the plant refers – retain the standard purplish color. Here the flowers are quite white.

Orchis quadripunctata f. albiflora – photo: Robert Crnković

Robert noted that all of these 14 plants have unspotted leaves – while the plants with purplish flowers have spotted leaves. This observation is conforming to the leaves of albiflora forms of other species like Dactylorhiza fuchsii which also lack the spots. The lack of Anthocyanine pigments affects not only the flowers but also the leaves.

Orchis quadripunctata f. albiflora – photo: Robert Crnković
Orchis quadripunctata f. albiflora – photo: Robert Crnković

Albiflora spring in Dalmatia

Himantoglossum robertianum – photo: Robert Crnković

Time and again, you can see the strong inflorescences of Himantoglossum robertianum in its hypochrome form. Jadranka Gubaš has now detected five of those plants at the coast near Šibenik, on a meadow with about 100 plants overall. Robert Crnković has taken the photos – thanks to both for this special greeting at the beginning of a new flowering season.

Himantoglossum robertianum
photo: Robert Crnković
Himantoglossum robertianum
photo: Robert Crnković

Albiflora forms on Alpine meadows

A highlight of the field trip to the Alpine region of Eastern Tyrol is a plant which on first sight appears as a stronger Pseudorchis albida. There are many of this species on the mountain meadows of the Golzentipp summit (2317 m) north of Obertilliach in the valley of Gail. Even more numerous is only Gymnadenia conopsea. But quite rare is the hybrid between both species. Studying the single flower it can be seen that this plant is such a Gymnadenia conopsea x Pseudorchis albida which has also been described as xPseudadenia schweinfurthii.

Size, lip form and length of spur are in the middle between Pseudorchis and Gymnadenia. But the color of the flower shows almost no influence of Gymnadenia conopsea flowering in purple violet. Only in the sepals there is a very faint hue of violet. Other findings of this hybrid, among them also some of the Golzentipp slopes, show flowers with a distinctive bright rose color. Thus, it may be assumed that this plant is a hybrid between an albiflora form of Gymnadenia conopsea and Pseudorchis. But it could also be possible that there is a mutation of a hybrid resulting in a lack of pigment development in the flowers.

Albiflora forms of Gymnadenia conopsea are quite common – on the Golzentipp meadows as well as above the Kircher Almen near Untertilliach at a similar height.

Dactylorhiza pythagorae f. albiflora

Foto: Kiros Kokkas

This orchid is only known from the Aeagean island of Samos. It is not variable, but in contrary unusually homogeneous, writes Wolfgang Eccarius in his book Die Orchideengattung Dactylorhiza (Eisenach 2016). But Kiros Kokkas found a white-flowered form of this rare orchid, which is usually flowering in pinkish to rose or mauve colors. This plant is obviously unique – but it also demonstrates that all the species of Dactylorizha tend to develop albiflora forms.

Foto: Kiros Kokkas

Lady’s Slipper without Chrysanthemin

Cypripedium calceolus

It’s very rarely that the Lady’s Slipper orchid (Cypripedium calceolus) is flowering without the brown-red color in sepals and petals. As with other orchid species this color is created by a pigment from the group of anthocyanines, called chrysanthemin. If this pigment is not produced, there are only carotinoids and chlorophyll left als coloring pigments. The results are yellow to greenish flowering plants. In contrast to Orchis or Dactylorhiza – but similar to Ophrys – the flowers of Cypripedium calceolus also contain chlorophyllum, thus participating in the photosynthesis.

No species of this genus has so many taxonomic descriptions of varieties as C. calceolus, writes Wolfgang Eccarius in his book Die Orchideengattung Cypripedium (Buergel 2009). In Thuringia, plants with pure yellow petals and sepals has been described as var. citrina by the teacher and botanist Bernhard Hergt (1858-1920), in Mittheilungen des Thueringischen Botanischen Vereins 1899, S.120f., indicated as f. citrinum by Eccarius.

A forma viridiflorum with greenish perigon (sepals and petals) has been described in the same journal in 1897 by Max Schulze (1841 – 1915). The author of the oldest of these descriptions is Alphonse Rion (1809-1856), who named a flava, a forma flavum, in his Guide du Botaniste en Valais, published in 1872.

Cypripedium calceolus

Those plants without Chrysanthemin also miss the common crimson dots on the staminodium at the entrance of the labellum.

Cypripedium calceolus

Orchis purpurea f. albiflora in Eastern Hesse

Orchis purpurea

Four decades after founding the Arbeitskreises Heimische Orchideen (AHO) Hessen (working group of native orchids Hesse) (on 3.3.1979), a conference in Sontra looks back and to the future. The meeting begins with a field trip to a heathland with juniper called “Buehlchen”, near Grossalmerode-Weißenbach (Werra Meissner district). Calcypedium is still in buds on May 18th, Neottia ovata has no inflorescence, but Orchis mascula ist beautifully flowering. Among them there are some plants with brighter flowers and an Orchis with a yellowish edge at its stigma.

Orchis mascula

In the afternoon, the AHO Hesse chairwoman Jutta Haas looks back: In the last 40 years we have done a lot. The first and still an important task is the field mapping of orchid places with the goal to protect and preserve them. The following lectures present the orchid flora in the North, the Middle and the South of Hesse – with interesting evidence of Albiflora forms, for example a group of five white-flowered Neotinea tridentata in North Hesse and the observation of Martin Hild: Dactylorhiza fuchsii is quite often flowering white in the mountain range of Taunus.

On the second day of the meeting there is a field mapping in the surroundings of Sontra. Near Moenchhosbach we record Platanthera chlorantha, Cephalanthera damasonium, Neottia ovata, Ophrys insectifera and Neotinea tridentata, which has an isolated occurence in Hesse and Thuringia – before I had only seen this species in the Mediterranean. It is interesting to observe the different color hues. Some plants are flowering quite bright, others haven intense crimson color.

In the afternoon we are visiting another heathland with Juniper near Berneburg, with Neotinea tridentata and efflorescent Orchis militaris. At a flower of Cardamine pratensis there was a couple of the orange-tip butterfly (Anthocharis cardamines).

Anthocharis cardamines

Finally we followed the hint of a conference participant and found the white-flowered Orchis purpurea, at the border of Hesse near Thuringia.

Orchis purpurea

Neotinea “immaculata” on Rhodes

In the pine forests of Profitis Ilias (798 m) on Rhodes, Neotinea maculata is still flowering in April. In addition to the common form with crimson spots on the tiny flowers with a labellum length of only 3 to 5 mm, there is also a pure white-flowered form. Labellum, sepals and petals don’t have the slightest hue. The leaves of these plants are also unspotted. So, the name of the species (maculatus – spotted) is turned into its opposite, and the plants appears as Neotinea “immaculata”, as unspotted Neotinea.

Among the other orchid species on Rhodes Anacamptis pyramidalis can be quite often found in its albiflora form – similar to its appearance in other regions.

White-flowered Orchis anatolica are less frequent than those forms of Anacamptis pyramidali. Even the light pink forms of this beautiful orchid are not very common. The crimson colour of the flowers seems to have a high genetical stability, at least on Rhodes.

“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.