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







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