Lizard orchid  (Himantoglossum hircinum)

This tall orchid carries up to 150 greenish-purple flowers on the flower spike (4)(7)(8). The common name refers to the flowers, which are said to look like lizards, with a long twisting tail and two 'legs' formed from the lips, and the petals and sepals forming the 'head' (4). The leaves are dull green in colour and often wither before the flowers open (8). The scientific name Himantoglossum derives from the Greek for 'strap-tongue' and hircinum is Latin for 'goat-like', this refers to the strong, foul smell of the flowers. In most other European languages it is known as '(Billy or male) goat orchid' (8).

This species is rare in the UK, and found locally in south east England (8)(9)(14). It was an extremely rare plant in England until the 1920s and was restricted to a handful of sites in Kent, but extended its range between 1920 and 1935 to a maximum of 35 sites, possibly because of warm weather (9)(10). The plant declined rapidly from the mid-1930s so that there were only 10 or 11 sites until the end of the 1980s. Between 1988 and 2001 the number of flowering plants in England expanded from approximately 1000 to over 6000 and the number of populations rose to 18 (8)(9), probably due to weather conditions that were suitable for seed production (11). Elsewhere, this orchid occurs in southern and western Europe (8).

Typical habitats are grassland, ancient earthworks, scrub, open woodland, road, track and path sides, quarries, railway banks and calcareous sands (six of the current populations in these habitats are on golf courses). It has also occurred under a hedge in a garden in Sussex, on a grass mound in a Mortello tower, on a retaining wall of a river and in a wood. Many of the sites are small, undisturbed patches rather than large open grasslands (7)(8)(9).

This perennial orchid may live for more than twenty years, but most plants flower irregularly and many only flower once (8)(11). It begins to flower from late May to early July (7)(8). The pollinating insects for this species have yet to be identified, although the wall mason wasp Odyneris parietum and solitary bees such as Megachile maritima in England and Colletes cunicularis in France have been seen with lizard orchid pollinia attached to them (8).

It can take years for a plant to reach the flowering stage (8)(11). Orchid seeds are tiny, dust-like particles and the lizard orchid has been estimated to produce from 0 - 1200 seeds per pod and up to 50 pods per flower spike (8)(11). The seeds do not contain sufficient reserves to allow them to germinate and like many orchids form an association with a mycorrhizal fungus, which supplies the nutrients needed to power germination and the early stages of growth (6)(8).

Leaves are winter-green in colour and are present from late August-October (depending on rainfall) to June, withering before or immediately after flowering. Non-flowering plants die back earlier in April or May. Except for fruiting spikes the plants persist for the summer as underground tubers (7) (8).

The main threat facing this species is loss of calcareous grassland through agricultural intensification. The species is at the northern extreme of its range in the UK, and is probably restricted by cool summer temperatures (9)(11), and is predicted to spread with a warming climate (9)(12)(13). Collecting has affected this species but is no longer a threat (8)(9).

As this species is fully protected under Schedule 8 of the Wildlife and Countryside Act (1981), it is illegal to pick, uproot or destroy plants, and to sell any part of the plant, living or dead (5).

For more on this species see:
Carey, P. D. & Farrell, L. (2002). Biological Flora of the British Isles: Himantoglossum hircinum (L.) Sprengel. Journal of Ecology 90: 206-218.

The New Atlas of the British and Irish Flora. By C. D. Preston, D. A. Pearman, and T. D. Dines (2002). Oxford University Press, Oxford, UK, p855.

Information authenticated by Peter Carey, Centre for Ecology and Hydrology.