Dactylorhiza ebudensis - Hebridean Marsh-orchid

Phylum: Magnoliophyta - Class: Liliopsida - Order: Orchidales - Family: Orchidaceae

Formerly known as Dactylorhiza majalis subsp. occidentalis, the Hebridean Marsh-orchid is endemic to Scotland and occurs only in the Outer Hebrides on the northern coast of North Uist.

Description

This is a short plant, growing to a maximum of 18cm in height but usually much shorter than that.

Leaves of the Hebridean Marsh-orchid are very distinctive: sharply pointed and with dark purple markings separated at the base, but which merge towards the points of the leaves so that they are often uniformly dark brownish-purple.

The flowers are deep magenta - reminiscent of the colour of the Northern Marsh-orchid (Dactylorhiza purpurella). Lateral sepals of the flower protrude outwards and upwards almost forming a vee-shape, and the upper sepal and petals form a hood over the column of the flower.

The lip (lower petal) is deeply lobed and has dark markings in the form of loops, dashes or spots which are sometimes almost indiscernible against the rich dark purple background colour of the petal itself.

Habitat

The best place to look for this orchid is in the species-rich coastal grasslands called the Machair, a calcium-rich habitat that is home to large numbers of chalk-loving wild orchids.

The Hebridean Marsh-orchid often occurs in small groups in the damper parts of the Machair which have been under water during the winter and early spring months and which retain a high level of moisture throughout the summer.

The Machair is a good place to see other wild orchid species including Early Marsh-orchid (Dactylorhiza incarnata), particularly its subspecies coccinea and the Northern Marsh-orchid (Dactylorhiza purpurella).

Flowering times

Hebridean Marsh-orchids flower from mid-May to mid-June.

Hybrids and Varieties

• Where the two species occur together, there may be hybrids with the Northern Marsh-orchid Dactylorhiza purpurella. The two species are closely related.
• A hyperchromatic variant is occasionally found.

Etymology

The genus name Dactylorhiza means 'finger-like roots', while the specific epithet ebudensis is the Latin name for the Hebridean Islands, where this orchid is found.

Acknowledgements

Pictures by kind permission of Andrew Cleave Nature Photographers Ltd.

Reference sources

The Plant List

Anne and Simon Harrap (2005) Orchids of Britain and Ireland; A&C Black

Pierre Delforge (2005) Orchids of Europe, North Africa and the Middle East; A&C Black