Taxonomy

Lycopodium clavatum | Stag's-horn Clubmoss

Distribution

Status

Conservation status


HABITATS DIRECTIVE ARTICLE 17 REPORTING*
RangeN/A
PopulationN/A
HabitatN/A
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)Least concern
Global (2)Not evaluated

Sources: (1) Dostalova, A. et al 2013 (2) The IUCN Red List of Threatened Species. Version 2014.2


Legal status

Protected by the following legal instruments:

  • Habitats Directive [92/42/EEC] Annex V
  • EU Wildlife Trade Regulation 318-2008

Native status

Native.

Species Biology

Identification

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. Selaginellaceae will also have a minute lobe, or ligule, on either side of the base of each leaf on the stem-facing side. Lycopodiaceae will have only the un-lobed kidney shaped microsporangia and lack the ligule seen in Selaginellaceae .

Lycopodium clavatum has a creeping, prostrate main stem and uptight branches.

The creeping main stem can reach to 1m but more usually to half that length.

The upright branches are much branched.These may reach 25cms.

Leaves are a bright green colour and arranged in spirals.

Leaves are to 5mm in length.

Leaves are minutely toothed and have a long (to 3mm) fine, white, apical, hair point.

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

Unlike other Irish Lycopodiaceae species the cones in Lycopodium clavatum are borne on long (to 10 cms) stalks on which the leaves up to the base of the cone are much more widely spaced than on the rest of the plant.

Cones are often in pairs on each long stalk.

Spores ripen July to September.

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



Adult habitat & habits


Habitat

Habitats include but are not necessarily limited to;

  • Dry siliceous heath (HH1) Upland
  • Wet Heath (HH3) Upland
  • Montane Heath (HH4)
  • Dry-humid acid grassland (GS3) Upland
  • Upland blanket bog (PB2)

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

Reproduction

The Stag's-horn Clubmoss (Lycopodium clavatum), 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 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 Lycopodium clavatum were attributed to ' a variety of pressures' including;
  • Agricultural improvement
  • Overgrazing
  • Burning
  • Habitat loss
  • Inappropriate grazing

Source: NPWS 2013.

The 2012 IUCN European regional assessment has Lycopodium clavatum classified as Least Concern for that region overall, however in some European countries it is assessed as either 'Critically Endangered' (Luxembourg), Endangered (Serbia), 'Vulnerable' (Germany), or 'Near Threatened' (Estonia, Hungary, Switzerland).

The account identifies current threats to the species and these include;

  • Abandonment of traditional land uses
  • Intensive agricultural practices / Eutrophication (increases competition and may damage mycorrhizal fungal partners).
  • Under-grazing
  • Succession
Source: Dostalova, A. et al 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.

As well as listing jurisdictions where the species is protected the 2013 IUCN European regional assessment for this species suggests the following conservation actions;

  • Manage sites in a way that Lycopodium clavatum can compete with other vegetation.
  • Monitor population trends.

Source: Dostalova, A. et al 2013

Distribution

World distribution(GBIF)

Circumpolar and most common at higher latitudes however it has been recorded from sub-tropical locations. No records from Australia or Antartica. Most records are from western Europe and from North America.

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

Records for the country are widespread but perhaps most frequent in the north of the island, otherwise quite scattered.

Temporal change

Records submitted to Data Centre in 2020

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 Lycopodium clavatum 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:

http://records.biodiversityireland.ie/

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 llysaght@biodiversityireland

References

Publications

Curtis, T.G.F.. and McGough H.N. 1988. The Irish Red Date List 1 Vascular Plants. Wildlife Service, Dublin.Published by The Stationery Office.

Dostalova, A., Gygax, A. & Rasomavicius, V. 2013. Lycopodium clavatum. The IUCN Red List of Threatened Species. Version 2014.2. <www.iucnredlist.org>. Downloaded on 12 November 2014..

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.

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.

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. <www.iucnredlist.org>. Downloaded on 12 November 2014.

Images