Bulbous buttercup to come when I get back from the bat survey.
Sunday, 8 June 2014
Thursday, 5 June 2014
Bod Petrual - Cheilosia and Buttercups
A really great Forestry Commission site in deepest Denbighshire, even if I didn't hear the hoped for wood warblers and Redstarts on my late morning visit today! This is one of the fine parts of the huge Glocaenog Forest.
This Cheilosia on Creeping Buttercup, Ranunculus repens, really ought to be the albitarsis/ranunculi group. The first thing to note is that this insect is a male with a blue-black thorax and slightly darkened wings, and generally dark legs:
This picture shows what appears to be a fairly dense covering of pale hairs on the eyes
Moving on to the more botanical side of things, the Cheilosia above is feeding on a Creeping Buttercup flower, Ranunculus repens (L.).
The Creeping Buttercup is a herbaceous, stoloniferous perennial growing to 50 cm tall. There are many named subspecies. It has both prostrate running stems, which produce roots and new plants at the nodes, and more or less erect flowering stems arising from a short stout "caudex" with a rosette of leaves. The basal leaves are divided into three broad normally stalked leaflets 1.5–8 cm long, shallowly to deeply lobed, borne on a 4–20 cm long petiole; leaves higher on the stems are smaller, with narrower leaflets. The leaves may be white-spotted. Both the stems and the leaves are finely hairy. The flowers are bright golden yellow, 2–3 cm diameter, usually with five petals. The nectaries are easily seen as tiny pockets at the base of the petals. The fruit is a cluster of achenes 2.5–4 mm long. It grows in fields, pastures, woods, gardens, parks, roadsides and wasteland and prefers wet soil.
Useful ID points are the spreading (not reflexed) sepals, the grooved stems and the stalked (petiolulate) terminal lobe of the trifoliate leaves. Interestingly there have been no reports of a mycorrhizal association.
Like most buttercups, Ranunculus repens is poisonous, although when dried with hay these poisons are lost. The toxin protoanemonin (apparently a break-down product of ranunculin) is not very stable and loses its potency when dry, so buttercup is not generally toxic in hay. The taste of buttercups is acrid, so cattle generally avoid eating them. The plants then take advantage of the cropped ground around it to spread their stolons.
Creeping buttercup spreads by seed and by long branching stolons that root at the nodes, forming new plants (ramets). The stolons may also regrow from cut portions to some extent. In more established woodland and grassland communities, this plant increases mostly through stolons unless the soil is disturbed. In dry conditions, flowering and seeding is more prevalent and in wet conditions, stolons are more plentiful. Seeds can germinate and seedlings can grow even under water-logged conditions. The plant is also said to be spread through the transportation of hay, implying that the seed may be present, I would imagine!
The plant is a serious invasive weed in places like North America and New Zealand. Here is a link to a useful Canadian paper on the biology of this minor threat to their ecosystems and agriculture. http://pubs.aic.ca/doi/pdf/10.4141/cjps90-135
One of the reasons creeping buttercup is so competitive is that its stolons respond to the environment. Under favourable conditions, plants form more stolons through branching. However, when nitrogen or water is limiting, stolons tend to be longer and un-branched allowing longer distance “sampling” of a number of potential sites until more suitable locations are found. When favourable conditions are discovered, stolon branching resumes, allowing rapid local colonization to take advantage of the available resources. In general, short stolons are produced in dense turf and much longer ones appear in open fields or woodlands.
Depending on the temperature, creeping buttercup either overwinters as a rosette or dies back to ground level. In either case, the nutrients stored in the short swollen stem produce rapid growth in spring, between April and June. Stolons grow from the leaf axils in spring and summer and growth peaks in late summer. Stolons connecting parent and daughter plants usually die off in autumn, leaving the plantlets separate.
Flowers can appear from March to August with seeds soon after. Each plant produces from about 20 to 150 (this may be an over estimate) seeds. Seeds can remain viable in the soil for at least 20 years, and up to 80 years, especially under acid or water-logged conditions. Seeds are dispersed by wind, water, birds, farm animals, rodents, and other animals by adhering to them with the hooked seeds. They exhibit dormancy and also sustained viability in the seedbank.
Excessive contact with the sap of the plant can cause skin blistering in humans, and various toxic effects in cattle if they eat it in excess because they there is little else and they are hungry. Unfortunately, livestock occasionally develop a taste for buttercup and consume fatal quantities.
The age of meadows up to 200 years old can be roughly estimated by the number of plants in 100 that have extra petals in their flowers - you get about 1 plant with flowers with extra petals for every 7 years old it is claimed. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2729631/ Mentioned in notes of nature. However the correlation coefficient is only moderate, in my view. This flower, photographed by chance a little further along the woodland path at Bod Petrual, turned out on closer examination to have 8 petals as far as I can see! I can just see 1 of the 3 sepals below I think.
and this one has 6 petals.
This on the other hand is another toxic plant, the Meadow Buttercup, Ranunculus acris, with a more finely dissected basal leaf. In this species there tend to be 5 (3 - 7) leaflets and in addition, unlike in the Creeping Buttercup, the middle (or each?) leaflet is un-stalked, giving a typical palmate rather than trifoliate appearance. The BSBI plant crib is very useful here: http://www.bsbi.org.uk/Ranunculus_Ranunculus_Crib.pdf
There is a photo below that of the characteristically even more dissected stem leaf. There were several scattered plants, in amongst or separated from the Creeping Buttercup, apparently it appears at random. There were very many fewer of this species, and I didn't happen to see any Cheilosia on them.
The very different, almost linear, un-stalked stem leaves of Ranunculus acris (L.) acris, the only subspecies found in the UK - although there are three different races!
The fairly common confusion species to Ranunculus repens is the Bulbous Buttercup, Ranunculus bulbosus, of drier grasslands, which has sepals that are reflexed in full flower. I saw this behind the dunes at Warkworth last week I believe.
In the Meadow Buttercup, the flower is similar to the flower of the Creeping Buttercup, with un-reflexed (spreading) sepals, but the flower stalk is, by contrast to the Creeping Buttercup, ungrooved. Another feature is the chromosomal number. Ranculus repens is generally a tetraploid plant (N = 32) based on N = 8, while Rancunulus acris is also a tetraploid (N = 28) based on N = 7.
There were plenty of other plants growing in profusion, and a few were even in flower. It was particularly nice to see the Cuckoo Flower, Cardamine pratense, so long after all the ones in Kent are long over.
This Cheilosia on Creeping Buttercup, Ranunculus repens, really ought to be the albitarsis/ranunculi group. The first thing to note is that this insect is a male with a blue-black thorax and slightly darkened wings, and generally dark legs:
This picture shows what appears to be a fairly dense covering of pale hairs on the eyes
Moving on to the more botanical side of things, the Cheilosia above is feeding on a Creeping Buttercup flower, Ranunculus repens (L.).
The Creeping Buttercup is a herbaceous, stoloniferous perennial growing to 50 cm tall. There are many named subspecies. It has both prostrate running stems, which produce roots and new plants at the nodes, and more or less erect flowering stems arising from a short stout "caudex" with a rosette of leaves. The basal leaves are divided into three broad normally stalked leaflets 1.5–8 cm long, shallowly to deeply lobed, borne on a 4–20 cm long petiole; leaves higher on the stems are smaller, with narrower leaflets. The leaves may be white-spotted. Both the stems and the leaves are finely hairy. The flowers are bright golden yellow, 2–3 cm diameter, usually with five petals. The nectaries are easily seen as tiny pockets at the base of the petals. The fruit is a cluster of achenes 2.5–4 mm long. It grows in fields, pastures, woods, gardens, parks, roadsides and wasteland and prefers wet soil.
Useful ID points are the spreading (not reflexed) sepals, the grooved stems and the stalked (petiolulate) terminal lobe of the trifoliate leaves. Interestingly there have been no reports of a mycorrhizal association.
Like most buttercups, Ranunculus repens is poisonous, although when dried with hay these poisons are lost. The toxin protoanemonin (apparently a break-down product of ranunculin) is not very stable and loses its potency when dry, so buttercup is not generally toxic in hay. The taste of buttercups is acrid, so cattle generally avoid eating them. The plants then take advantage of the cropped ground around it to spread their stolons.
Creeping buttercup spreads by seed and by long branching stolons that root at the nodes, forming new plants (ramets). The stolons may also regrow from cut portions to some extent. In more established woodland and grassland communities, this plant increases mostly through stolons unless the soil is disturbed. In dry conditions, flowering and seeding is more prevalent and in wet conditions, stolons are more plentiful. Seeds can germinate and seedlings can grow even under water-logged conditions. The plant is also said to be spread through the transportation of hay, implying that the seed may be present, I would imagine!
The plant is a serious invasive weed in places like North America and New Zealand. Here is a link to a useful Canadian paper on the biology of this minor threat to their ecosystems and agriculture. http://pubs.aic.ca/doi/pdf/10.4141/cjps90-135
One of the reasons creeping buttercup is so competitive is that its stolons respond to the environment. Under favourable conditions, plants form more stolons through branching. However, when nitrogen or water is limiting, stolons tend to be longer and un-branched allowing longer distance “sampling” of a number of potential sites until more suitable locations are found. When favourable conditions are discovered, stolon branching resumes, allowing rapid local colonization to take advantage of the available resources. In general, short stolons are produced in dense turf and much longer ones appear in open fields or woodlands.
Depending on the temperature, creeping buttercup either overwinters as a rosette or dies back to ground level. In either case, the nutrients stored in the short swollen stem produce rapid growth in spring, between April and June. Stolons grow from the leaf axils in spring and summer and growth peaks in late summer. Stolons connecting parent and daughter plants usually die off in autumn, leaving the plantlets separate.
Flowers can appear from March to August with seeds soon after. Each plant produces from about 20 to 150 (this may be an over estimate) seeds. Seeds can remain viable in the soil for at least 20 years, and up to 80 years, especially under acid or water-logged conditions. Seeds are dispersed by wind, water, birds, farm animals, rodents, and other animals by adhering to them with the hooked seeds. They exhibit dormancy and also sustained viability in the seedbank.
Excessive contact with the sap of the plant can cause skin blistering in humans, and various toxic effects in cattle if they eat it in excess because they there is little else and they are hungry. Unfortunately, livestock occasionally develop a taste for buttercup and consume fatal quantities.
The age of meadows up to 200 years old can be roughly estimated by the number of plants in 100 that have extra petals in their flowers - you get about 1 plant with flowers with extra petals for every 7 years old it is claimed. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2729631/ Mentioned in notes of nature. However the correlation coefficient is only moderate, in my view. This flower, photographed by chance a little further along the woodland path at Bod Petrual, turned out on closer examination to have 8 petals as far as I can see! I can just see 1 of the 3 sepals below I think.
and this one has 6 petals.
This on the other hand is another toxic plant, the Meadow Buttercup, Ranunculus acris, with a more finely dissected basal leaf. In this species there tend to be 5 (3 - 7) leaflets and in addition, unlike in the Creeping Buttercup, the middle (or each?) leaflet is un-stalked, giving a typical palmate rather than trifoliate appearance. The BSBI plant crib is very useful here: http://www.bsbi.org.uk/Ranunculus_Ranunculus_Crib.pdf
There is a photo below that of the characteristically even more dissected stem leaf. There were several scattered plants, in amongst or separated from the Creeping Buttercup, apparently it appears at random. There were very many fewer of this species, and I didn't happen to see any Cheilosia on them.
The very different, almost linear, un-stalked stem leaves of Ranunculus acris (L.) acris, the only subspecies found in the UK - although there are three different races!
The fairly common confusion species to Ranunculus repens is the Bulbous Buttercup, Ranunculus bulbosus, of drier grasslands, which has sepals that are reflexed in full flower. I saw this behind the dunes at Warkworth last week I believe.
In the Meadow Buttercup, the flower is similar to the flower of the Creeping Buttercup, with un-reflexed (spreading) sepals, but the flower stalk is, by contrast to the Creeping Buttercup, ungrooved. Another feature is the chromosomal number. Ranculus repens is generally a tetraploid plant (N = 32) based on N = 8, while Rancunulus acris is also a tetraploid (N = 28) based on N = 7.
There were plenty of other plants growing in profusion, and a few were even in flower. It was particularly nice to see the Cuckoo Flower, Cardamine pratense, so long after all the ones in Kent are long over.
Tuesday, 3 June 2014
Cliffe
As I arrived, over-encumbered with gear, a car drew up beside me and asked me the best path to the Black-winged Stilts! I denied any knowledge but was tempted enough to head towards Flamingo rather than the usual lookout over Radar pool. Having admired the Avocet chicks I finally came across the Black-winged Stilts elsewhere, guarded 24/7 by a very mice but very tough looking chap with a dog partner, a large Alsatian.
He doesn't generally train the dog to bite (too much paperwork if there is an incident) but simply to leap up and knock the perpetrator over, - this usually knocks the wind out of the baddy, possibly breaking a rib or two in the process, and the absence of biting reduces the risk of the dog being separated from his handler by the police after the incident, which even if only temporary, would be unthinkable and intolerable to both.
This is the male Black-winged Stilt (very henavily cropped) standing guard
and this is the female (even more heavily cropped) incubating the eggs on the nest, just to the right of the standing male.
The scrub was fairly full of birds, Whitethroats, Linnets, Goldfinches, Nightingales, Blackbirds and here is a nice Long-tailed Tit.
and here is a male Cuckoo, that was calling for a long time from this area of scrub by the Flamingo Pool::
There were a lot of Black-headed Gull chicks around, and here is one that had got into the water.
Sunday, 1 June 2014
Whetsted Gravel Pits
There was a single Common Tern, Sterna hirundo, fishing the gravel pits stylishly and successfully! In the first picture, where the bird is dark against the lightness of the sky, I think I can see the light (sometimes called translucent) panel in the middle of the wing that is said to help to distinguish this bird from the Arctic Tern, Sterna paradisaea, where much more of the wing is said to be translucent. That I don't find this convincing says rather more about my very poor skills as a birdwatcher than it does about Tern field characteristics!
Rather clearer here are the black tip to the otherwise comparitively light red bill, and the not excessively long tail streamers. It is also easier to see the black outer webs on primaries P10 - P5.
Above I think I would only just agree that the dark trailing edge to the wings in the outer primary section bleeds well forward into the rest of the wing but on the lower side there is a limited and sharper dark trailing edge. This does not taper off inwards. A limited dark trailing edge not bleeding forwards to form a dusky wedge on the upper side is said to be more characteristic of the Arctic Tern, and the dark trailing edge on the underside should taper off inwards in that species.
The bird seemed reasonably successful and the one time I followed a dive a small fish was apparently fairly easily taken, as shown below. Common Terns are said to be more likely to dive directly rather than hover briefly before diving as Arctic Terns are generally said to do (Bird Forum), and this bird seemed to halt, twist (bank sharply) and dive almost back on itself but nearly vertically into the water, perhaps flattening out a bit as it hit the water surface. However BWP claims that they do hover but less rapidly than the Arctic. It would be interesting to follow the sequence more exactly with high speed shooting, or even video.
Common Terns are flexible feeders but generally are dive-plunge feeders, often but not always submerging 20 - 30 cm. They also surface feed or even plunge from perches. The main prey is fish, but the diet also includes shrimps and other crustacea as well as insects perhaps taken from the surface. This particular bird just seemed to be plunge-diving for fish!
A more important point though is why hasn't it eaten the fish instantly, as BWP claims it should have done.. Where is it taking it? To a partner or a nest? Or is this bird just passing through, and just being slow to eat its catch?
Perhaps its not too surprising to see an individual inland, but its difficult to know if this is just migrating through the area, or perhaps specifically looking for an inland site to breed upon. This could be a late migrating bird, just arrived following the long journey North from the wintering grounds of West Africa. What a pity there are no nesting rafts on these pits. Once a pair has chosen a nest site they may return to the same site year after year (17 years is apparently the current record until one of the pair failed to return).
After fledging and learning to fish on their own, juveniles may start to move South either in family groups or small flocks of juveniles only. They may trek backwards and forwards for anything up to 3-4 years before first breeding, but sometimes breeding can start at 2 years old. When they are old enough to breed, they may breed in the colony they were born in, or nearby.
Mates do not seem to associate closely in the winter quarters, but arrive at the nest site paired up, having found each other perhaps in the winter quarters prior to departure, on passage, or in and around the colony. They arrive initially at a roost close to the colony and already paired birds can be recognised by roosting closer to each other than the average.
Once the next territory is established it is used for courtship, copulation, pair-bonding, nesting and initially (up to 23 days) concealing and feeding the young.
Population is about 15,000 in UK, fairly stable and the smaller inland population appears to be growing. This pattern not repeated consistently across Europe.
Rather clearer here are the black tip to the otherwise comparitively light red bill, and the not excessively long tail streamers. It is also easier to see the black outer webs on primaries P10 - P5.
Above I think I would only just agree that the dark trailing edge to the wings in the outer primary section bleeds well forward into the rest of the wing but on the lower side there is a limited and sharper dark trailing edge. This does not taper off inwards. A limited dark trailing edge not bleeding forwards to form a dusky wedge on the upper side is said to be more characteristic of the Arctic Tern, and the dark trailing edge on the underside should taper off inwards in that species.
The bird seemed reasonably successful and the one time I followed a dive a small fish was apparently fairly easily taken, as shown below. Common Terns are said to be more likely to dive directly rather than hover briefly before diving as Arctic Terns are generally said to do (Bird Forum), and this bird seemed to halt, twist (bank sharply) and dive almost back on itself but nearly vertically into the water, perhaps flattening out a bit as it hit the water surface. However BWP claims that they do hover but less rapidly than the Arctic. It would be interesting to follow the sequence more exactly with high speed shooting, or even video.
Common Terns are flexible feeders but generally are dive-plunge feeders, often but not always submerging 20 - 30 cm. They also surface feed or even plunge from perches. The main prey is fish, but the diet also includes shrimps and other crustacea as well as insects perhaps taken from the surface. This particular bird just seemed to be plunge-diving for fish!
A more important point though is why hasn't it eaten the fish instantly, as BWP claims it should have done.. Where is it taking it? To a partner or a nest? Or is this bird just passing through, and just being slow to eat its catch?
Perhaps its not too surprising to see an individual inland, but its difficult to know if this is just migrating through the area, or perhaps specifically looking for an inland site to breed upon. This could be a late migrating bird, just arrived following the long journey North from the wintering grounds of West Africa. What a pity there are no nesting rafts on these pits. Once a pair has chosen a nest site they may return to the same site year after year (17 years is apparently the current record until one of the pair failed to return).
After fledging and learning to fish on their own, juveniles may start to move South either in family groups or small flocks of juveniles only. They may trek backwards and forwards for anything up to 3-4 years before first breeding, but sometimes breeding can start at 2 years old. When they are old enough to breed, they may breed in the colony they were born in, or nearby.
Mates do not seem to associate closely in the winter quarters, but arrive at the nest site paired up, having found each other perhaps in the winter quarters prior to departure, on passage, or in and around the colony. They arrive initially at a roost close to the colony and already paired birds can be recognised by roosting closer to each other than the average.
Once the next territory is established it is used for courtship, copulation, pair-bonding, nesting and initially (up to 23 days) concealing and feeding the young.
Population is about 15,000 in UK, fairly stable and the smaller inland population appears to be growing. This pattern not repeated consistently across Europe.
Friday, 30 May 2014
Thursday, 29 May 2014
Little Gulls at Cresswell, and Druridge Pools
What a pretty little gull, that I didn't take enough notice of!
Two Avocets, 7 Black-tailed Godwits, 4 Shelduck, 1 Grey Plover, 2 Redshank, 4 Mallard, about half a dozen Tufted Duck, and a wonderful view of a Sedge Warbler. A Newcastle birder told me that there were two Reed Warblers singing behind the hide, but I didn't hear either of them, a bit worrying. A good group of House Martins with a few Swallows
At Druridge Pools I took Monty along the path to the two hides that I had found yesterday. There were Greylag Geese, 1 male Shoveller, Mallards, House Martins, Swallows, Black-headed Gulls. On the path on the way back I tried to photograph a Whitethroat, and heard Willow Warblers and Chiff Chaffs.
Two Avocets, 7 Black-tailed Godwits, 4 Shelduck, 1 Grey Plover, 2 Redshank, 4 Mallard, about half a dozen Tufted Duck, and a wonderful view of a Sedge Warbler. A Newcastle birder told me that there were two Reed Warblers singing behind the hide, but I didn't hear either of them, a bit worrying. A good group of House Martins with a few Swallows
At Druridge Pools I took Monty along the path to the two hides that I had found yesterday. There were Greylag Geese, 1 male Shoveller, Mallards, House Martins, Swallows, Black-headed Gulls. On the path on the way back I tried to photograph a Whitethroat, and heard Willow Warblers and Chiff Chaffs.
Wednesday, 28 May 2014
Hauxley Nature Reserve
Monty and I popped in very briefly. Monty was OK on the permissive paths as long as he kept his lead on, and fair play to him, he was very good in the hide, settling down quickly to snooze on the wooden floor.
I misidentified the orchid a Pyramidal from the deep colour, but it was of course Northern Marsh Orchid, Dactylorhiza purpurella. A wide spreading (sometimes referred to as diamond-shaped apparently) lower lip, with darker cerise markings over the purple ground, topped by a plain hood and two "flying" wings (typical for Dactylorhiza?). There are broad basal and sheathing stem leaves. It grows in generally damp but not not acid habitats. The flower spike is often said to look a bit broad-topped and stumpy - these two are not fully out yet.
The cerise markings should be all over the lip, not just near the centre, according to one of the websites - this looks good enough!
This is the commoner subspecies purpurella, not growing more than 35 cm, with leaves that tend to be unspotted, except for occasional light spotting at the tip. The flowers tend to be a deep pink rather than purple, and it can grow well away from the sea, as opposed to ssp. majaliformis, found typically in places like the Hebridees. According to Kew in 2005 ssp majaliformis is a synonym and the correct name is ssp cambrensis (Wood, 2005). http://aplx5.rdg.ac.uk/annual-checklist/2009/show_species_details.php?record_id=5028937.
The maroon spotting is described in Francis Rose as heavy - the Southern Marsh Orchid's spotting is by contrast described as light, and those flowers are wider, over 1.9 cm wide. The Southern takes over in the SouthEastern half of the country, except for a Northern Marsh Orchid outlier in the New Forest in Hampshire.
The species appears to have occurred more or less as an as an allotetraploid from a nybrid between D. incarnata and D. fuchsii/maculata, as apparently several other species have, such as D. majalis, traunsteineri, sphagnicola and lapponica. On the other hand D. maculata has been interpreted as an autotetraploid of D. fuchsii. http://archive.bsbi.org.uk/Wats21p113.pdf
The poor genetic isolation and the morphological intergradation in areas of sympatry of many of the members of the genus Dactylorhiza may indicate that treatment of the allotetraploid marsh-orchids as taxonomic species may not be justified. They might be better treated as subspecies of a single variable species, D. majalis, as suggested by some recent studies (e.g. Bateman & Denholm 1983; lenkinson 1991; see also Sundermann 1975; S06 1980). This subspecific status still recognizes that these taxa may have evolved independently, and that they have at least partly different distributions and contrasting habitat requirements. It is interesting to think about the timing of their origins, and the different land masses they occur in.
http://www.leedingain.com/2013/06/orchid-confusion-in-northumberland-7.html
I misidentified the orchid a Pyramidal from the deep colour, but it was of course Northern Marsh Orchid, Dactylorhiza purpurella. A wide spreading (sometimes referred to as diamond-shaped apparently) lower lip, with darker cerise markings over the purple ground, topped by a plain hood and two "flying" wings (typical for Dactylorhiza?). There are broad basal and sheathing stem leaves. It grows in generally damp but not not acid habitats. The flower spike is often said to look a bit broad-topped and stumpy - these two are not fully out yet.
The cerise markings should be all over the lip, not just near the centre, according to one of the websites - this looks good enough!
This is the commoner subspecies purpurella, not growing more than 35 cm, with leaves that tend to be unspotted, except for occasional light spotting at the tip. The flowers tend to be a deep pink rather than purple, and it can grow well away from the sea, as opposed to ssp. majaliformis, found typically in places like the Hebridees. According to Kew in 2005 ssp majaliformis is a synonym and the correct name is ssp cambrensis (Wood, 2005). http://aplx5.rdg.ac.uk/annual-checklist/2009/show_species_details.php?record_id=5028937.
The maroon spotting is described in Francis Rose as heavy - the Southern Marsh Orchid's spotting is by contrast described as light, and those flowers are wider, over 1.9 cm wide. The Southern takes over in the SouthEastern half of the country, except for a Northern Marsh Orchid outlier in the New Forest in Hampshire.
The species appears to have occurred more or less as an as an allotetraploid from a nybrid between D. incarnata and D. fuchsii/maculata, as apparently several other species have, such as D. majalis, traunsteineri, sphagnicola and lapponica. On the other hand D. maculata has been interpreted as an autotetraploid of D. fuchsii. http://archive.bsbi.org.uk/Wats21p113.pdf
The poor genetic isolation and the morphological intergradation in areas of sympatry of many of the members of the genus Dactylorhiza may indicate that treatment of the allotetraploid marsh-orchids as taxonomic species may not be justified. They might be better treated as subspecies of a single variable species, D. majalis, as suggested by some recent studies (e.g. Bateman & Denholm 1983; lenkinson 1991; see also Sundermann 1975; S06 1980). This subspecific status still recognizes that these taxa may have evolved independently, and that they have at least partly different distributions and contrasting habitat requirements. It is interesting to think about the timing of their origins, and the different land masses they occur in.
http://www.leedingain.com/2013/06/orchid-confusion-in-northumberland-7.html
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