This page could equally have been called the scientific or controversial page

Bill's Dactylorhiza technical page

This page could equally have been called the scientific or controversial page, our son refers to it as "Hardcore" you have been warned!!

This page will be concentrating on the Dactylorhizas found in England - always controversial taxa. At the end of the page are the references that I have used, I have used a number of books which can be divided into what are known in England as "lumpers or splitters" i.e. those who think that there a lots of varieties or subspecies of a given species, and those who think that there are lots of species. I have used the 'splitters' names, as they are shorter as their actual status is still under debate.

It has already been established that D. fuchsii and D. incarnata are the parents of all the other Dactylorhizas I am therefore inclined to regard D. fuchsii, D. incarnata and possibly D. maculata as being the ONLY species and the remainder as being either hybrids, sub-species or forms. Looking at Dactylorhizas in countries other than Britain suggests that variations in the parents of local colonies have lead to a proliferation of names for orchids that have only slightly different morphology.

Clicking on the thumbnails will give larger images.

These photographs are of D. fuchsii, the close-up, of an unusually patterned flower, was taken in Austria, near the German border. The second, more typically patterned specimen, was photographed in Northern England. Generally there were no easily visible differences between specimens in the two countries. They tend to grow in alkaline or neutral damp places, but will tolerate drier conditions than other Dactylorhizas.

D. fuchsii is diploid, normally it has 2n = 40 chromosomes. The leaves are usually dark green with large and very distinct spots on them.

Pedersen referred to a Dactylorhiza that had alleles present in D. fuchsii as having "F" characteristics.

Using this nomenclature D. fuchsii is "FF".

These photographs are of D. incarnata, the first was taken in Oxfordshire, England and is a typical pale specimen. The second photograph of D. incarnata var. pulchella. was taken near the South Coast in Sussex. The third photograph was taken in South Wales in an area of dune slacks and is a typical example of what is called D. incarnata var. coccinea. I cannot comment on the variation between all countries as I have only seen D. incarnata var. ochroleuca in Germany and D incarnata in Sweden that resembles either the pale common British form, or a red (but not var. coccinea) colour form. It tends to grow in wet alkaline or neutral places. It is characterised by narrow unspotted leaves with tips that are hooded.

D. incarnata is diploid, normally it has 2n = 40 chromosomes. The leaves are normally pale green and unspotted.

Pedersen referred to a Dactylorhiza that had alleles present in D. incarnata as having "I" characteristics.

Using this nomenclature D. incarnata is "II".

These 4 photographs are of D. maculata, the first two from Eastern Germany, the third from Northern England and the last from Oxfordshire, England. There are clear differences in the size and shape of the labellum between the the specimens from the two countries. Some regard the English specimens as being D. maculata var. ericetorum, and some as D. ericetorum. It tends to grow in neutral or acid damp or wet places. This species arises when D. fuchsii reproduces in such a way that it doubles the number of chromosomes from 40 to 80. There is therefore the potential for this species to spontaneously arise at any D. fuchsii site. It should be noted however that the two species have different preferences for soil pH and moisture levels, this means that at a neutral damp site the two species with their hybrids can co-exist happily. If conditions are not damp and neutral then the tetraploid is likely to die out, but may flower first and result in the production of hybrids between itself and D. fuchsii that are more suited to the local pH and moisture level. This is possibly the explanation for the appearance of orchids at many old sites that seem to have labellum's that are intermediate between those of D. fuchsii and D. maculata.

D. maculata is an autotetraploid which normally has 2n = 80 chromosomes. Using the Pedersen nomenclature it is "FFFF".

When we come to the allotetraploids things become more complicated. Bateman et al were "unable to adequately resolve the various allotetraploids". They did however find that within the allotetraploids the D. majalis group (including D. praetermissa & D. alpestris) and the D. traunsteineri group (including D. lapponica & D. elata) could be separated by a four step branch plus an indel (insertion-deletion event). They also reported that the D. traunsteineri group had identical ITS sequences despite their contrasting morphologies and the discovery of an allozyme difference between D. traunsteineri and D. elata. A surprise finding was that the ITS sequences of D. fuchsii and D. traunsteineri were closer than the 3 sequences obtained for a single sample of D. praetermissa (to me this implies three different parents, suggesting that the sample may have been a hybrid of D. praetermissa). I will refer to these orchids as if they are species - the botanists will have to sort out whether they are species, sub-species or varieties!

In the Pedersen nomenclature the following orchids were all "FFII" - D. majalis, D. praetermissa, D. lapponica, D purpurella, D. rusowii, D. spagnicola & D traunsteineri. They normally have 2n = 80 chromosomes.

This is a photograph of D. majalis taken in Eastern Germany. When D. fuchsii is present, orchids with ring markings on their labellum's are present. Generally it looks similar to the following photograph, but tends to be a darker colour than D. praetermissa. It tends to grow in wet places and has spots on the leaves.

This photograph of D. praetermissa was taken in Oxfordshire, England at a site which contained no other species of orchids. When this species occurs with D. fuchsii there are many orchids present which have impressive stature, leaves shaped like D. praetermissa, some at the base of the stem, with leaf spots like D. fuchsii, and it can be difficult to find any orchids without ring markings on the labellum. It tends to have broad unspotted leaves. Further discussion and illustrations appear at the end of this page.

This photograph of D. purpurella was taken in Northern England where it replaces D. praetermissa. This orchid is generally a much deeper purple colour and shorter in stature than D. praetermissa or D. majalis. It has broad unspotted leaves.

This photograph of D. traunsteineri was taken in Southern Germany, the locals regard the dark purple stems, the narrow leaves and lack of ring markings on the labellum as being indicators that the orchid is D. traunsteineri. In other countries however ring markings are common and the criterion seems to be narrow leaves and not D incarnata or D cruenta. It tends to grow in very wet places.

This photograph of D. traunsteineriodes was taken in Oxfordshire, England. Although this plant has narrow leaves and no ring marks on the labellum and tends to grow in very wet places, it looks very different to the above.

Pedersen stated that :-

The hybridization "FF" x "FFII" has been recorded many times.

That "FF" x "II" is rare or none existent.

That "FFFF" x "FFII is known.

That "FF" x "FFFF" is known.

Pedersen also stated that f1 hybrids generally exhibit reduced fertility.

D. incarnata and D. fuchsii (or D. maculata) are the parents of all of the allotetraploid Dactylorhizas. This seems to be consistent with all three papers, but raises the problem of apparently rare "FF" x "II" hybrids, as the allotetraploids are "FFII". Could it be that the hybrids are common, but that we see them as being different species, rather than hybrids? Alternatively, is the rarity of the cross the reason that "FF" and "II" characteristics are still distinguishable? Has anyone tried to hybridize them in the laboratory?

Some of the above questions have now been answered -

(1) "FF" x "II" hybrids are present, where D. incarnata and D. fuchsii are common at the same site. I have seen one site in Sussex in which the offspring of the purple flowered D incarnata (var pulchella) and D. fuchsii are indistinguishable from D. praetermissa var junialis, D. purpurella and D praetermissa. The first being much more common than the other two. Update on this site in May 2005 - the orchid flora of the young site has changed dramatically, I found it very difficult to find any purple flowered D. incarnatas. Even the normal pink form of D. incarnata was much less evident and tetraploid hybrids were clearly starting to dominate. The reason for this may be changing rainfall patterns and droughts, producing conditions that are less favourable to D. incarnata, which likes a wet habitat.

(2) John Haggar has successfully crossed D. incarnata and D. fuchsii and flowered the hybrids.

(3) I have seen a single example of D. maculata at a site that otherwise contained only D. fuchsii, this presumably was a result of chromosome doubling.

The main question now is what should we call the allotetraploid Dactylorhizas - different species, sub-species or different varieties or forms of different hybrids? I am now inclined towards regarding them as different forms of hybrids, or sub-species, rather than species as I believe that the "species" are still being created.

The definition of a species is still vague, until it is fixed the "splitters" will continue to invent new species, and publish books full of them. One book published in 1995 listed approximately 94 species of Dactylorhizas and probably contains even more in the latest version.

If you have views on the above please send me an E mail.

Perhaps when Dr Richard Bateman produces his next paper I will have to modify this page - time will tell!

SOUTHERN MARSH ORCHID - Dactylorhiza praetermissa or D. majalis var praetermissa.

This is a controversial species - Pierre Delforge says that the cauline leaves are not blotched, (but blotched in var. junialis)... labellum 7-10 mm long, 8-14 mm wide, entire or trilobed, subrhombohedral to oblong-cordate, flat to folded longitudinally, base and centre paler, decorated, sometimes widely with spots and fine dashes, violet, often fanning out, margins more coloured, not marked. very variable polymorphic species, with a cline of morphological variations partly covering those of D. elata, D. spagicola,& D. longifolia, among others, and often intergressed with D. maculata s.l., which explains the uncertainties in its distribution.

There are a couple of points that this raises - the first is that ring marks are not mentioned in its patterning on the labellum and the second is variety junialis, which is characterised by leopard like spots on the leaves - I personally suspect that this variety is actually a hybrid with D. fuchsii (the Common spotted orchid), or other Dactylorhizas.

Leaf spots on Dactylorhiza leaves is unfortunately a "plastic" feature, I have a hybrid Dactylorhiza which produces many Leopard spots on its leaves when growing in the shade, put only a few small sized spots when growing in full sun.

I have been looking carefully at a local site which was created (as an anti-flood measure) in 1983 and which subsequently became an orchid site. It contains many Southern marsh orchids (still more than half the population in 2003) plus some Common spotted orchids and a good number of orchids which I regard as hybrids. The interesting thing is that there are so many Southern marsh orchids that the hybrids stand out - they are all paler than Southern marsh orchids, they have distinct rings on the labellum, and leaf spots some of them are leopard spots. My personal view is that if a "Southern marsh orchid" has leaf spots and distinct rings on the labellum then it is a hybrid. The following photographs are all from this site.

There is also a widespread confusion about what D praetermissa looks like, primarily caused by problems of colour reproduction in photographs, this has resulted in many hybrids of D purpurella, D majalis and D fuchsii being regarded as D praetermissa.

Dactylorhiza praetermissa

All the following plants have no spots on the leaves, and no ring marks on the labellum, there are many hundreds of orchids looking exactly like these at the above site, and at other sites.

Hybrids of Southern marsh & Common spotted orchids

All of the following plants have leaf spots, the plants in the first row have plain spots and those in the second row have leopard spots (rings).

Mix

LEOPARD SPOTTED ORCHID - Dactylorhiza praetermissa var junialis

This variety, is characterised by leaves with Leopard (ring shaped) spots. These spots are present on many hybrids of D. praetermissa & D. fuchsii. Orchid colonies containing large numbers of the dark purple form of D. incarnata and D fuchsii seem able to produce hybrids that I can't distinguish from D praetermissa, D. praetermissa var. junialis and D. purpurella. Perhaps the purple form of D. incarnata and D. fuchsii are the parents of all the Dactylorhizas commonly occurring in Britain. I have also seen a single Dactylorhiza with European type D. maculata shaped labellum growing in the middle of a colony of D. fuchsii in Warwickshire that had leopard spotted leaves. I have also seen D. majalis hybrids in Italy and Austria with leopard spots.

The following photograph is of a hybrid orchid with very distinct leopard spots, but it is clearly not a form of D majalis.

Some years ago I purchased Dactylorhiza fuchsii "Bressingham Bonus" from a nursery and planted it in alkaline clay soil in my garden. During the first few years the plants survived, had maybe 4 or 5 pin head sized spots in total on their leaves and flowered only once. When they flowered I concluded that they were probably hybrids of D. majalis var praetermissa and D. fuchsii. I eventually moved them to a sunken bucket containing commercial alkaline compost, then they started to produce leaves with many larger spots and they flowered every year. I then decided to cover the surface of the compost with limestone chippings in order to prevent weeds from growing with them. Plants surrounding this bucket were also growing strongly and providing shade. For the 3 years after I did this the leaves were covered with leopard spots i.e. spots with a green centre. Since the surrounding vegetation has been removed the leaves the leopard spots have been replaced by a few small solid spots.

I therefore suspect that leaf spotting is affected either by fungi, soil pH, shade or mineral content, in addition to any genetic effects. The size and intensity of spots is clearly plastic in that an individual plant can change its leaf spots depending upon the prevailing conditions. Hybrids can appear with purple leaves that age to give leopard spots. It is well known that leaf spots tend to fade during the flowering period.

I think that there is long way to go before the Dactylorhizas are fully understood.

References -

Pridgeon, A M, Bateman, R M, Cox, A V, Hapeman, J R, Chase, MW 1997. Phylogenetics of subtribe Orchidinae (Orchidoideae, Orchidaceae) based on nuclear ITS sequences. 1. Intergeneric relationships and polyphyly of Orchis sensu lato. Lindleyana 12(2): 89-109.

Bateman, R M, Pridgeon, A M, J R, Chase, MW 1997. Phylogenetics of subtribe Orchidinae (Orchidoideae, Orchidaceae) based on nuclear ITS sequences. 2 Infrageneric relationships and reclassification to achieve monophyly of Orchis sensu stricto. Lindleyanaa 12(3): 131-141

Pedersen, H Æ 1998. Species concept and guidelines for infraspecific taxonomic ranking in Dactylorhiza (Orchidaceae) - Nord. J. Bot. 18: 289-310.

Delforge, P 1995 Collins Field Guide ORCHIDS of Britain & Europe. ISBN 0-00-220024-4