Spotted Orchids (better late than never)

I saw a few spotted orchids during a rainy walk yesterday, so I thought I would try to get a representative sample while the lowest flowers were just opening. In my opinion, this is when an orchid plant looks best: once the higher flowers are open, the lower ones can look very untidy and spoil the overall look. As usual, I will give my assessment of what species are present in each specimen, with rationale. The three 'species' photographed are Common Spotted Orchid (CSO), Heath Spotted Orchid (HSO) and Northern Marsh orchid (NMO). 

Characteristics used:

CSO has white to pink flowers with a clearly pointed centre lip and pointed outer lips

HSO has white to pink flowers with a continuous frilled lip and only a small point, if present

NMO has purple flowers with a smooth continuous lip. Flowerhead usually squat. Flowers earlier than the previous two species.

This first one looks to be pretty well 50/50 CSO/HSO due to the pale colour and the fringed outer lips with a spiked centre lip.

Common Spotted Orchid x Heath Spotted Orchid

This specimen looks to be pure CSO due to the three-pointed lip:

Common Spotted Orchid

This appears to have all three parents, with a central tooth, frilled outer lip and darker colour:

Hybrid Spotted Orchid

This appears to be mostly NMO, due to the darker colour and continuous, unfrilled, toothless lip, but the upper flowers are tending to pale and the spike is quite tall:

Hybrid Spotted Orchid

This paler specimen is mostly CSO, with a touch of HSO due to the slightly frilled/rounded outer lip:

CSO/HSO

This looks to be a very clean NMO, due to the short spike, already fully-open flowers, darker colour and continuous lip, but there is a tiny hint of frilling, so we have to consider some HSO:

NMO/HSO

A good, clean CSO (triple teeth with almost no frilling):

Common Spotted Orchid

This is clearly part CSO (long central tooth) and HSO (frilled outer lips):

CSO/HSO

Note that the central flower in the above spike is still rotating clockwise into its 'upright' position.

This last shot shows, I think, a triple hybrid between HSO, CSO and NMO. There is a clear frill round the lip, there is a central tooth and the colour is quite dark with a shorter spike:

Triple hybrid Spotted Orchid

I cropped that last shot to include the Heath Woodrush on the left.

Please note: the differentiation between Dactylorhiza orchids is contentious at best and uncertain at worst. I also believe that they tend to vary according to micro-habitat, with specimens with wet feet tending towards HSO and those with dry feet tending towards CSO. The variability in your area might well be different.

More on orchids

It has been suggested that really robust specimens like this one are showing 'hybrid vigour'. Since I consider them all to be hybrids, I rather think their environment might just have something to do with it instead.


The next sequence shows the gently graded colour variation from lilac to white:


That last one with no colouration whatsoever and yellow pollinia is known as Dactylorhiza fuchsii, ssp. o'kellyi, and is confined to western Ireland. No comment.


I raced to have a close look at these two when I saw them, and sure enough, the spike is short and the lower lobes are really frilly. A perfect Heath Spotted Orchid?

Not in my book...they just happened to be the only two with their feet submerged in the stream, and were less than a metre away from identically-coloured CSO with dry feet.

Still with orchids in mind, have a look at this shot of the hoverfly Helophilus pendulus:

Notice anything?

The hoverfly has some green objects stuck to its antennae. A much closer zoom in shows that they are, in fact, the pollinia of an orchid:

They must be quite irritating to the hoverfly, because it was quite clearly trying to remove them. Maybe hoverflies aren't perfectly built for this pollination task.

Dactylorhiza orchids

The main flush of Dactylorhiza orchids has appeared. These are always at their best when the lowest rank of flowers has just newly opened.

For years, there has been a huge debate about the number of species and descriptions of the species and hybridisation. It is known that they hybridise and back-cross, so I suggest that most specimens are an intermediate 'hybrid' amongst 3 key 'species' in our location: Common Spotted Orchid (CSO), Heath Spotted Orchid (HSO) and Northern Marsh Orchid (NMO). Given that these 'species' hybridise so regularly, I can't see any uncorrupted ones being possible, so I rather think that we are taking a few distinguishing characteristics and lumping individuals into one bucket or another, depending on what we see.

This one shows the main features of 'CSO'...tall spike, three very clear lobes to the base of the flower, very little frilling:



This one shows more influence of 'HSO', with much frillier lips and a slightly shorter spike.

This would appear to have some NMO influence...much darker markings and a still shorter spike:


I'll leave the next few to your own imagination.

The lower left flower in this specimen shows the nectar hole being clearly indicated by the purple lines, which act as a guide for insects. The hole suggests that these species need a long-tongued insect like a butterfly or bee to pollinate them. Pollination is carried out via the pair of brown pollinia which attach pollen to the back of the pollinating insect.


This last one, however, shows a nice feature. The flowers form 'upside down', and only then do they rotate to their final position.

That last one would be pure 'CSO' if it wasn't for the (very) short spike.

Late edit:

Gill mentioned in her comments that the inverted flower looks more developed than usual. This is true. A close look reveals that the 'lower' lip has developed too quickly and has jammed against the flower above it. This combination of features will prevent the flower from passing on any pollen, so this is the end of the line for that combination.