Diphasiastrum alpinum | Alpine Clubmoss



Conservation status

Future ProspectsN/A
Overall  Assessment of Conservation StatusInadequate
Overall Trend in Conservation StatusStable
* In the Habitats Directive Article 17 reporting guidance for the period 2007-2012 particular members of the famiies Lycopodiaceae and Huperziaceae occuring in Ireland are required to be reported on as a group, unless a member state (in this case Ireland) is of the opinion that individual species within the group may require special attention. In Ireland, for the period 2007-2012, none of the species in this group was identified as requiring special attention.

The Conservation Status in the table above is then for the entire group rather than for the individual species.

Source: NPWS 2013; European Topic Centre on Biological Diversity.

IUCN Conservation Status
Ireland Not evaluated
Europe (1)Not evaluated
Global (1)Not evaluated

Sources: (1) The IUCN Red List of Threatened Species. Version 2014.2 2014.

Legal status

Protected by the following legal instruments:

  • Habitats Directive [92/42/EEC] Annex V

Native status


Species Biology


The Clubmosses (Lycopodiaceae), and related Spikemosses -also commonly known as Lesser Clubmosses- (Selaginellaceae), look superficially like mosses, however there are some very important distinctions.Lycopodiaceae and Selaginaellaceae  have an organised vascular system including roots for the transport of water,a thick leaf cuticle and, often, a leaf covered rhizome; mosses do not.

Source: Merryweather, James 2007.

In Lycopodiaceae and Selaginellaceae sporangia are borne on the stem facing side of modified leaves (sporophylls). In the Irish Selaginellacea these sporophylls are distributed in 'zones' on branches, in most of the Irish Lycopodiaceae the sporophylls are concentrated in a distinct leafy 'cone' terminally on branches.

The key distinction between Lycopodiaceae and Selaginellaceae is in the sporangia. Selaginellaceae have two types - megasporangia and microsporangia bearing different sized spores.These can be distinguished by eye as the megasporangia on the Selaginellaceae are four lobed and the microsporangia an un-lobed kidney shape. Lycopodiaceae will have only the un-lobed kidney shaped microsporangia. Selaginellaceae will also have a minute lobe on either side of the base of each leaf on the stem-facing side.

Diphasiastrum alpinum has a creeping, prostrate main stem and upright branches.

The creeping main stem can reach to 1m but more usually to half that length, and appears somewhat flattened.

The upright branches are branched again, eventually achieving a fan-like shape. These may reach 5-10cms.

Upright branches do not appear flattened.

Leaves are a glaucous (blue-green) colour and arranged in alternate, opposite pairs.

Leaves are entire and lack a fine hair point.

Upright branch eaves attached to stem towards their base, and arranged in four neat vertical rows.

Sporangia bearing sporophylls are in cones that are terminal on upright branches.

Bud-like plantlets in leaf axils do not occur.

Spores ripen June to August.

Sources: Rose, Francis 1989; Stace, C. 1997.


Habitats include but are not necessarily limited to;

  • Montane heath (HH4)
  • Dry-humid grassland (GS3) Montane only.
  • Exposed siliceous rock (ER1)
  • Siliceous scree and loose rock (ER3)
  • Eroding blanket bog (PB5) Montane only.

Sources: Parnell J., Curtis T., 2012; Stace, C.1997; Rose, Francis. 1989; Hill, M. O. et al 1999; Fossitt, J.A. 2001

Life stages

The Alpine Clubmoss (Diphasiastrum alpinum), in common with other Lycopodiaceae, displays classic alternation of generations, with a diploid sporophyte generation and a haploid gametophyte generation. In the case of Clubmosses the sporophyte is the obvious 'plant' identified in the field.

The sporophyte generation produces spores. A spore, on germination produces a 'prothallus' containing male and female organs, the haploid gametophyte generation. Following fertiliztion a new sporophyte develops, nurtured by the prothallus.

Sources: Merryweather, James 2007.

Threats faced

In the Article 17 Habitats Directive reporting for the period 2007-2012 no current threats were listed for this species in Ireland. In that reporting period the named Lycopodiaceae species of the Habitats Directive occurring in Ireland were given an 'Overall Assessment of Conservation Status' of 'Inadequate' due to;

  • Ongoing pressures, particularly inappropriate grazing regimes, on the habitats where they occur.
Historic declines of range and site numbers for named Lycopodiaceae species, including Diphasiastrum alpinum were attributed to ' a variety of pressures' including;

  • Agricultural improvement
  • Overgrazing
  • Burning
  • Habitat loss
  • Inappropriate grazing

Source: NPWS 2013.

Conservation actions

In the Article 17 Habitats Directive reporting for the period 2007-2012 no Conservation Measures in place or in the process of being implemented during the period were listed for this species.

Source: NPWS 2013.


World distribution(GBIF)

In Europe records are concentrated in Norway, northern Finland, Britain, Ireland, the Pyrenees, the Alps and Iceland with scattered records from southern Greenland.

On north America, scattered records from eastern Canada and far north eastern United States. More records from western Canada, Alaska and the Aleutian islands.

Accuracy of world distribution shown in the Global Biodiversity Information Facility (GBIF) map below will be constrained by, amongst other factors, data held but not shared by countries and organizations not participating in the GBIF.

Irish distribution

Most records from mountainous areas in Wicklow and Galway and Northern Ireland. Historic records from the Ivereagh (pre-1930) and Dingle (pre-1970) peninsulas in Kerry however there is a recent re-discovery of it in Kerry.

There has been a recent record also from the Comeragh mountains in Co. Waterford from 2010.

Sources: Roche, J.R., 2011; Hodd, R.L. & Roche, J.R.(in press Jan. 2015).

Temporal change

Records submitted to Data Centre in 2023

The following map is interactive. If you would prefer to view it full screen then click here.

How can you help

The National Biodiversity Data Centre is trying to improve our knowledge of the distribution of Diphasiastrum alpinum in Ireland. Should you observe this species, please submit sightings to add to the database. Detailed observations will assist us gaining a better insight into where the species is most abundant in Ireland and we might also be able to detect regional variations. Please submit any sightings and photographs at:

All records submitted online can be viewed on Google Maps – once checked and validated these will be added to the database and made available for conservation and research.

Further information

For further information contact Dr. Liam Lysaght



Fossitt, J.A. 2001. A Guide to Habitats in Ireland. The Heritage Council.

Hill, M. O. Mountford, J. O., Roy D. B. & Bunce R. G. H. 1999. ECOFACT 2a Technical Annex - Ellenberg’s indicator values for British Plants. Institute of Terrestrial Ecology: Huntingdon.

Hodd, R.L. & Roche, J.R. Diphasiastrum alpinum (L.) Holub (Alpine Clubmoss) rediscovered in Co. Kerry (H1). Irish Naturalists’ Journal (in press Jan. 2015).

Merryweather, James.2007. The Fern Guide; A field guide to the ferns, clubmosses, quillworts and horsetails of the British Isles, Third Edition.Field Studies Council.

NPWS 2013. The Status of EU Protected Habitats and Species in Ireland.  Species Assessments Volume 3. Version 1.0. Unpublished Report, National Parks & Wildlife Services. Department of Arts, Heritage and the Gaeltacht, Dublin, Ireland.

Parnell J., Curtis T., 2012. Webb's An Irish Flora. Cork University Press.

Roche, J.R. & Perrin, P.M. (2010) A new county record for alpine clubmoss (Diphasiastrum alpinum) from the Comeragh Mountains, Co. Waterford (H6). Irish Naturalists’ Journal 31 (2) 149-150.

Roche, J.R. (2011) New records for Diphasiastrum alpinum L. (Holub) and their implications for the species’ conservation status in Ireland. Irish Botanical News 21: 16-20.

Rose, Francis. 1989. Colour Identification Guide to the Grasses, Sedges, Rushes and Ferns of the British Isles and north-western Europe. The Penguin Group. London.

Stace, C.1997. New Flora of the British Isles, Second Edition. Cambridge University Press.

The IUCN Red List of Threatened Species. Version 2014.2. <>. Downloaded on 11 November 2014.