The genus Himantoglossum is not well delimited, and speciation processes as well as hybridization among species seem to take place frequently, at least in certain parts of its distribution area (Bernardos et al. 2006). Genetic relationships (ITS nuclear rDNA) seem to justify the establishment of an expanded Himantoglossum clade that incorporates the former monotypic genera Barlia and Comperia (Bateman et al. 2003). Of the nine Himantoglossum species recognized by Bateman et al. (2003), five species have also been classified as subspecies of H. hircinum by other sources:
- H. hircinum (L.) Sprengel
- H. adriaticum H. Baumann
- H. caprinum (M.-Bieb.) Sprengel
- H. calcaratum (G. Beck) Schlechter
- H. affine (Boissier) Schlechter
Chromosome No.: 2n = 24, 36 (Stace 2010).
Photography: K. Swift.
Distinction between species and subspecies is complicated, hindering the exact identification of their range. The striking inflorescences of the sub-Mediterranean Lizard Orchid (Himantoglossum hircinum) can be found across Europe, from Spain eastwards to the Balkans and in western North Africa. In Spain, populations are sparse with sites located in Northern Spain, Southern Spain and Central Spain often at high altitudes (Diez 1985). This is in contrast to the frequent occurrence of the species in France, where it grows in all regions except Finistére (northwest France) and Corsica (Bournérias & Prat 2005). In the British Isles, H. hircinum ssp. hircinum has been restricted mostly to the south and east of England. Populations occur in Kent and Sussex (at about sea-level, often on golf courses), Somerset and Devon, in Gloucestershire and on the North and South Downs. In Germany, populations are scattered, often bound to southward-facing slopes, which create warmer microclimates. H. hircinum ssp. hircinum is found in the mountains of Cilento NP (Dr. Antonio Croce) and Pollino NP in the South of Italy. It does not occur in North Italy, Hungary, Croatia, Czech Republic and Slovenia (where H. adriaticum is present). While the species is predominantly restricted to calcareous grasslands, it is also found on sand or gravel.
Our current database (grid resolution of 1 km x 1 km) on population entries contains 385 absence records and 1008 presence records in seven European countries. Further presence and absence recordings of H. hircinum, as well as additional information for presence records including site history, site management, geology and vegetation cover, will help to improve accuracy of the habitat model developed.
AFLP and plastid marker analyses of H. hircinum ssp. hircinum across its European distribution suggests the existence of major migratory pathways during postglacial range expansion (Pfeifer et al. submitted). Also, populations in the Southern Italy refugium are genetically isolated from the rest of Europe. We suspect an old contiguous distribution of H. hircinum (European distribution) and H. adriaticum (Balkan distribution) with hybridization in the contact zone in Southern Italy (Passalacqua 1998). Intermediate forms exist in great abundance and hybridization is suspected to take place in locations where both species occur together. Gene flow could be analysed by including H. adriaticum into plastid and AFLP marker analyses. Some H. adriaticum populations are currently investigated in Hungary by Dr. Judit Bodis (Bódis & Botta-Dukát 2008 ).
Morphometric and demographic measurements
By accompanying genetic analyses with morphometric (e.g. flower shape, colour) and demographic (e.g. size class distribution, life state transition probabilities) measurements will allow a better understanding of drivers of the species’ distribution including historical population processes and environmental changes. At the moment, there are 16 permanent monitoring sites scattered throughout Europe (two in Germany, two in South France, two in North France, two in South England, two in South Spain, one in Switzerland, one in Belgium and four in Italy). At each site, size class distribution of individually labeled plants is measured within subplots. Also, flowers are collected in 70% ethanol and photographed with a macro-lens. Results from further sites anywhere in Europe would contribute to our understanding of demographic variability of plants across spatial scales.
The species’ pollination biology is largely unknown. Major pollinators appear to be Andrena spp. (Kropf & Renner 2008). Plants are usually rewardless, although nectar production was reported for some populations in the past (Teschner 1980). There is a need of studying more populations with regard to nectar production (presence/absence; amount; consistency), flower odour (geographical variation, correlation with genetic population structure), capsule size and pollinator specifity.
A rare plant species in the UK, it is listed as near threatened (NT) in the Red Data List for Great Britain (2005). However, the species has recently experienced increases in abundance and population numbers at its north-eastern range margin - namely in Southern England and Germany, indicating a range shift (Good 1936; Carey 1999). Because of its rarity it is listed as endangered in Germany.
Photography: M. Pfeifer
Current and future research
The research MODGLOB - funded by the German research Community (DFG) - has been established in Potsdam University in 2007 in the research group of Prof. Florian Jeltsch. It involves several researchers providing expertise in population genetics, pollination ecology, comparative morphometry, population ecology, and habitat modelling. MODGLOB analyses population structure and dynamics of H. hircinum ssp. hircinum on locations throughout the species' range to understand stress-response and genetics of populations in a large-scale spatial context (Central-Marginal concept), and to identify factors shaping the species’ realized environmental niche. Detailed genetic and isotopic analyses have been carried out and a Bayesian habitat model is currently developed. For further details on the research and first results please contact the project coordinator Dr. Marion Pfeifer (Potsdam University, Germany). We are happy to provide support with additional ideas/studies/sampling involving the species.
Please contact Dr. Marion Pfeifer.
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- Bernardos, S. et al. 2006. Phylogenetic relationships of Mediterranean Neottieae and Orchideae (Orchidaceae) inferred from nuclear ribosomal ITS sequences. Acta Botanica Gallica, 153, 153-165.
- Bódis J & Botta-Dukát Z 1998. Growth of Himantoglossum adriaticum and H. caprinum individuals, and relationship between sizes and flowering. Acta Botanica Hungarica, 50: 257-274.
- Bournérias M & Prat D 2005. Les orchidées de France, Belgique et Luxembourg. Second edition, Biotope (Parthenope Collection), Mèze France, p. 504.
- Carey PD 1999. Changes in the distribution and abundance of Himantoglossum hircinum (L.) Sprengel (Orchidaceae) over the last 100 years. Watsonia, 22, 353–364
- Carey PD & Farrell L 2002. Himantoglossum hircinum (L.) Sprengel. Journal of Ecology, 90, 206–218
- Carey PD et al. (2002. The sudden increase in the abundance of Himantoglossum hircinum in England in the past decade and what has caused it. In: Underlying mechanisms of trends and fluctuations in terrestrial orchid populations (eds) Kindlman P, Willems J, Whigham D), pp. 187-208. Backhuys Publishers, Leiden.
- Diez FJF 1985. Distribución en España peninsular de Himantoglossum hircinum (L.) Sprengel. Anales Jardines Bot. Madrid, 42, 187-190.
- Good R 1936. On the distribution of lizard orchid (Himantoglossum hircinum Koch). New Phytologist, 35, 142–170.
- Jacquemyn H et al. 2005. Does nectar reward affect rarity and extinction probabilities of orchid species? An assessment using historical records from Belgium and the Netherlands. Biological Conservation, 121, 257-263.
- Kropf M & Renner S 2008. Pollinator-mediated selfing in two deceptive orchids and a review of pollinium tracking studies addressing geitonogamy. Oecologia, 155, 497-508.
- Pfeifer M, Wiegand K, Heinrich W, Jetschke G 2006a. Long-term demographic fluctuations in an orchid species driven by weather: implications for conservation planning. Journal of Applied Ecology, 43, 313-324.
- Pfeifer M, Heinrich W, Jetschke G 2006b. Climate, size and flowering history determine flowering pattern of an orchid. Botanical Journal of the Linnean Society, 151, 511-526.