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.

a biased learning experience – how pollinators react to color

Bees and other insects are looking for floral rewards, such as nectar and pollen. And they learn to associate a variety of floral cues, including color with such rewards, as three researchers of the University of Arizona – Avery L. Russell, China Rae Newman and Daniel R. Papaj – explain in an article published this year in Evolutionary Ecology (DOI 10.1007/s10682-016-9848-1). Yet, we don’t know much about the ways how insects are learning.

Andrea spec. with Orchis simia
Andrea spec. with Orchis simia

The Arizona project looks for plants with different colors due to a single loss-of-function mutation blocking the production of floral pigments. Similar to the albiflora orchids presented on this web site, such color polymorphisms may also occur in other plant families. The authors explain that those are quite common, for example with Geranium thunbergii, Antennaria dioica or Aquilegia coerulea – a relative to the European Aquilegia vulgaris.

Aquilegia vulgaris
Aquilegia vulgaris

There study analyzes the behavior of pollinators of hypochromic Solanum tridynamum in an experimental arrangement. It could be shown that initially naïve bees had no preference for purple- or white-flowered plants. The same was the case when the researchers prevented the release of pollen – this was done by sealing the anther pore with glue. But bees with a rewarding experience on plants with purple corollas expressed strong, significant landing preferences for morphs with purple corollas relative to morphs with white corollas. This preference to the rewarding color was much weaker in the case of rewarding flowers with white corollas. The authors came to the conclusion: bees showed a bias in terms of how experience shaped preference: experience with the purple morph had a greater effect on preference than experience with the white morph.

The reason for this bias in learning might be, according to the Arizona researchers, that purple flowers exhibit much greater chromatic contrast, so the hypochromic Solanum tridynamum is likely even less discriminable in real-world foraging conditions. Such biases, the authors conclude, might curtail the success of such morphs and perhaps even contribute to the low frequencies in which they occur. The Arizona case study titled White flowers finish last: pollen-foraging bumble bees show biased learning in a floral color polymorphism is great research – there should be others to follow to see if pigmented flowers have an a priori advantage over hypochromic flowers.

Orchis purpurea in the Abruzzo mountains

Orchis purpurea
Photo: Christian Schlomann, 28/05/206, Campo Imperatore/Abruzzo, Italy

Christian Schlomann has visited the Abruzzo mountains and sent me this beautiful Orchis purpurea. Campo Imperatore is a mountain grassland in the Gran Sasso massiv, in an altitude between 1500 and 1900 meters.

new year greetings from Croatian island Korčula

Orchis quadripunctata

Starting into 2015 I received a nice mail from Mirjana and Nebojša Jeričević living on the Dalmatian island of Korčula. They sent me photos of albiflora forms of five species, Orchis quadripunctata (above), Anacamptis pyramidalis, Himantoglossum robertianum, Dactylorhiza romana and Orchis italica. Especially interesting are those of Dactylorhiza romana. Those plants show some light yellowish hue but are not as yellow as the common yellow form of this bi-coloured species. They are are growing among violet forms and it might be assumed that they are plants whose flowers should have been violet but lost the anthocyanins pigments.

Dactylorhiza romana

Dactylorhiza romana

white flowering in Engadine

Visiting this Eastern region of Switzerland, my special interest was focussed on Epipogium aphyllum, flowering in dark forests. “Aphyllum” refers to the lacking of any leafs – and so they don’t have any chlorophyll. Some plants also miss anthocyanins – the Swiss expert of the region, Joe Meier, sent me a a photo of a totally white flower found recently. He pointed out that this form could not only be addressed as albiflora, but also as albino – following the definition of a plant without any pigments. I’ve found a plant with reduced anthocyanin in its lip, while a rose hue is still slightly existent:

Epipogium aphyllum

The trip to the region near the charming town Scuol also confirmed the slightyl increased tendency of Gymnadenia to develop albiflora forms. While there has been quite a lot of Gymnadenia conopsea with a marked purple colour, I also met a white-flowering plant:

Gymnadenia conopsea

Gymnadenia conopsea

Most of Gymnadenia odoratissima tend to a very bright purplish colour while retaining some visible hue of it. But on a mountain meadow there was also a plant without any anthocyanin in the flowers, even the column being yellowish-whitish:

Gymnadenia odoratissima

Orchis olbiensis – Andalusian chromatics

orchis_olbiensis

Orchis olbiensis has a colourful and a light variety, as it is stated by Kretzschmar/Eccarius/Dietrich in “Die Orchideengattungen Anacamptis, Orchis, Neotinea” (Buergel 2007, p. 322). The light variety has flower colours between rose and almost white – with a colourful lip pattern contrasting to the light background. The white-flowered plant comprises almost half of the populations in Spain, the authors observed – quite in difference to the almost purplish flowers of Orchis olbiensis in France.

Five years after visiting Orchis olbiensis for the first time in Southern France, I had now the chance to study Orchis olbiensis in Southern Spain, in the province of Malaga. Though in mid-April I’ve been quite late for this species, I found two albiflora forms of Orchis olbiensis in the limestone formation of the Torcal, near the small town of Antequera. The greater plant had nine almost white flowers with the fine purplish dots still conserved. In this habitat there were also growing Anacamptis papilionacea, Ophrys scolopax and Orchis mascula subsp. laxifloraeformis.

orchis_olbiensis_2

a dream in green and white: Ophrys apifera in Basel

Finally, I’ve met her: The bee orchid at the Rhine port of Basel which has been described as Ophrys apifera var. basiliensis – in 2006, Paul Delforge “downgraded” her to Ophrys apifera f. basiliensis.

Ophrys apifera var. basiliensis

My Swiss friend Klaus Hess has told me a couple of years ago about this special population of bee orchids. Now we met at Basel and took the bus to a place called Waldhaus. There, we walked to the bank of the Rhine. Between the railway tracks and the river, limited between the container terminal to the West and the old Auhafen to the East, there is a small strip of grassland quite rich with species. Dominated by Bromus erectus, there is also growing Knautia arvensis, Geranium pyrenaicum, Leucanthemum vulgare and other flowers.

Basel Rheinhafen

Soon Klaus found the first of these special bee orchids. They are special not only due to their lack of pigments, but also to the special form of the petals. Those are sepaloid, much longer and broader than usual with bee orchids. We are just in the beginning of the flowering time. As Klaus was looking for further plants I studied the flower with my camera – and observed the rare visit of an Andrena bee at a bee orchid. It was just a visit, not a pollination at all, though the bee carried pollen from other flowers. Ophrys apifera is autogamous, and the yellow pollinia are soon falling down to perform self fertilisation.

Ophrys apifera var. basiliensis

The next surprise on this Ascension holiday was meeting Stefan Schwegler, who has described those bee orchids as Ophrys apifera var. basiliensis (in: Orchid Review 112/2004).

Basel Rheinhafen

He showed us a couple of other plants, among them a regular Ophrys apifera with its brown and yellow pigments as well as Platanthera chlorantha, Anacamptis pyramidalis and Dactylorhiza fuchsii. And he told us about the permanent struggle to conserve this special place against commercial interests of the port management. The population of Ophrys apifera var. basiliensis is declining, Stefan Schwegler explained, but still consists of about 100 plants. Most of them don’t flower every year, but wait for their moment to appear.

Albiflora forms of Dactylorhiza saccifera and cordigera

Dactylorhiza saccifera f. albiflora
Though Dactylorhiza fuchsii is developing albiflora forms more often than other European orchids, especially in certain regions (Ireland, some German regions), there are no mentions of white-flowered Dactylorhiza saccifera. Both species are diploid and related with each other. Exploring the marsh areas of the Smolikas mountain in mid-June in Northern Greece, I’ve seen this splendid Dactylorhiza saccifera f. albiflora on wet grounds, in a height of 1200 m, embedded in Marsh Horsetails (Equisetum palustre) and accompanied by Dactylorhiza baumanniana and Neottia ovata.
Dactylorhiza saccifera f. albiflora

In the same area there was also a white-flowered Gymnadenia conopsea with a slight purple hue.

Another highlight of the field trip to Northern Greece: three white-flowered Dactylorhiza cordigera on a clearing in the Vitsi mountain range near Kastoria. Those were surrounded by more than 1,000 cordigera plants with their characteristic deep purple colour.
Dactylorhiza saccifera f. albiflora

The picture of albiflora forms of late flowering orchids in Northern Greece was completed by a Dactylorhiza incarnata f. albiflora near the village of Chrisi:
Dactylorhiza incarnata