Much fuss is made in books about the various species of Dactylorhiza orchids, especially in relation to their hybrids. I recognise two local 'species': Northern Marsh Orchid - Dactylorhiza purpurella and Spotted Orchid - Dactylorhiza fuchsii/Dactylorhiza maculata. The reason I bracket the last pair is because I simply believe we have a continuum of variations, with one extreme looking like Dactylorhiza fuchsii and the other extreme looking like Dactylorhiza maculata. These are - in my opinion - all hybrids, since they are known to cross and back-cross, so what we have is a hybrid swarm, with all variations in petal shape and colour being present in more or less the same locality. The following Spotted Orchids were all found within a few metres of each other.
The first two are classic 'Common Spotted Orchids', but are very pale:
The next specimen is more towards the 'Heath Spotted Orchid', but still with a single tooth on a wide, rounded base:
Another variant has extremely elegant flowers which are slim in all the parts.
A few years ago, I carried out an extensive survey of my local orchids. The result is here:
To further fuel the debate, I also think that Spotted Orchids vary according to micro-climate (humidity, soil type, etc.) and that the precise variation depends on locality (your mileage may vary).