Dactylorhiza purpurella Northern Marsh-orchid: identification, distribution, pictures

As its name suggests, the Northern Marsh-orchid has a predominantly northerly distribution in the UK and Ireland, with its populations in West Wales being at the most southerly part of its range. Apart from the complications caused by hybrids with spotted orchids it is, relative to some Dactylorhiza species, fairly straightforward to identify. The flowers are a deep magenta and have distinctly diamond-shaped lips that are only very slightly tri-lobed. The inflorescence has a flattened top, and the leaves are either unmarked or only sparsely marked with a few spots. The exception to this is the subspecies which occurs in Wales, Dactylorhiza purpurella subsp. cambrensis, which has numerous dark spots on the leaves. Northern Marsh-orchid grows in a number of mainly alkaline habitats, although it is also able to tolerate mild acidity. Good places to look for this orchid are marshy fields, roadside verges, fens, marshes and sand-dune slacks that remain damp throughout the year. Occasionally, Northern Marsh-orchid will colonise drier places such as old waste tips and abandoned quarries. Dactylorhiza purpurella flowers from late-May to mid-July. This European endemic plant is also found in northwesterly parts of Norway, Sweden and Denmark.

Distribution Map		Key Features
	Records for the Northern Marsh-orchid from BSBI are shown on the map with most recent in front. (Hover the mouse over the small map to expand it.) CLICK HERE to visit the BSBI website page for updated data and maps with separated data for individual record periods.	Plant: 5 to 45cm tall; stem green flushed pink to purple towards the top, robust, ribbed and hollow. Leaves: up to 8 semi-erect broad lanceolate-oval green leaves towards the base of the stem above a single basal leaf; green, unmarked or sparsely spotted. Bracts: green, flushed purple. Flowers: from 10 to 40 (sometimes up to 80 on large plants), deep magenta and velvety, held on a cylindrical inflorescence that has a flattish top. The upper sepal and petals form a loose hood over the lip, which is barely tri-lobed and distinctly diamond-shaped. The lip is white towards the base and has dark dots and loops throughout.

Image Gallery for Northern Marsh-orchid Dactylorhiza purpurella

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Title of album Description of album
Title of album Description of album

Pollination

Taxonomy & Hybrids

Little detailed information is available, but Northern Marsh-orchid is known to be pollinated by bees. Seed set is good.

The specific name 'purpurella' means 'purple'.

Subspecies: Dactylorhiza purpurella subsp. cambrensis occurs in Wales and is described above.
Varieties: Dactylorhiza purpurella var. pulchella has flower lips with spots and dashes rather than loops; it is recorded in Scotland. Dactylorhiza purpurella var. crassifolia has broader leaves and the flowers have larger lips; it is rare. Dactylorhiza purpurella var. maculosa has overall small dots on the leaves and the lip of the flower is paler; it is recorded from Scotland. Dactylorhiza purpurella var. albiflora has white flowers. Dactylorhiza purpurella var. atrata is hyperchromatic and has very dark flowers and darkly marked leaves; it is known from a heavily contaminated location near Hartlepool.
Hybrids: Dactylorhiza x formosa is a hybrid with Heath Spotted-orchid Dactylorhiza maculata. Dactylorhiza x venusta is a hybrid with Common Spotted-orchid Dactylorhiza fuchsii. Dactylorhiza x viridella is a hybrid with Frog Orchid Dactylorhiza viridis. Dactylorhiza x insignis is a hybrid with Southen Marsh-orchid Dactylorhiza praetermissa. Dactylorhiza x latirella is a hybrid with Early Marsh-orchid Dactylorhiza incarnata.
Intergenetic hybrids: X Dactylodenia varia is a hybrid with one of the Fragrant Orchids Gymnadenia spp.

Articles about Northern Marsh-orchid in JHOS