Lycopodiella inundata | Marsh 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 (1)Vulnerable*
Europe (2)Not evaluated
Global (3)Least Concern

Sources: (1) Curtis, T.G.F.. and McGough H.N. 1988; (2) The IUCN Red List of Threatened Species. Version 2014.2 2014.(3) Lansdown, R.V. 2014.

* This Red List is acknowledged as needing to be updated. The Red List category shown is updated from that appearing in the original 1988 document, due to changes to the IUCN Red List categories since then.

Source: Curtis, T.G.F. and McGough H.N. 1988.

Legal status

Protected by the following legal instruments:

  • Habitats Directive [92/42/EEC] Annex V
  • Wildlife Act (1976)
  • Flora Protection Order 1999
  • Wildlife (Amendment) Act (2000)
  • Wildlife (N.I.) Order 1985*
*As Lycopodium inundatum.

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, or main stem; 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 (or using a hand lens) 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.

Lycopodiella inundata has a creeping, prostrate main stem and upright branches.

The creeping main stem can reach between 5 and 20cms.

Creeping stem is only slightly branched and dies back to terminal buds in winter.

The upright branches are un-branched.These may reach 10cms but are usually less.

Leaves are a bright green colour and arranged in spirals.

Leaves are to 6mm in length.

Leaves are lanceolate and do not have fine, white, apical, hair point.

Sporophylls similar to stem leaves but broader at the base.

Sporangia bearing sporophylls are in cones that are terminal on upright branches, however due to similarity between stem leaves and sporophylls cones are not as distinct as in some other Lycopodiaceae.

Cones are borne singly on erect stalks. These stalks bear leaves that are arranged equally along their entire length. In Lycopodium clavatum the leaves on cone stalks are much more widely separated than on the rest of that plant.

Spores ripen June to September.

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


Lycopodiella inundata has been most often recorded from bare peat that may be flooded.

Source: Stace, C.1997.

Habitats include but are not necessarily limited to;

  • Wet heath (HH3)
  • Bogs (PB)
  • Dystrophic lakes (FL1) Lake margins.
  • Acid oligotrophic lakes (FL2) Lake margins.

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


The Marsh Clubmoss (Lycopodiella inundata), 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 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.
For Lycopodiella inundata specifically the indequate status was also related to;

  • Drainage.
  • Habitat loss.
Historic declines of range and site numbers for named Lycopodiaceae species, including Lycopodiella inundata  were attributed to ' a variety of pressures' including;

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

Source: NPWS 2013.

The 2014 IUCN Global assessment has Lycopodiella inundata classified as Least Concern overall, however in some European countries it is assessed as either 'Critically Endangered' (Croatia), Endangered (U.K.), 'Vulnerable' (Estonia, Switzerland), or 'Near Threatened' (Sweden).

The account identifies the main threats to the species as;

  • Habitat degradation
  • Habitat loss
Source: Lansdown, R.V. 2014.

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 2014 IUCN Global assessment for this species suggests the following conservation action;

  • Monitor for losses
Source: Lansdown, R.V. 2014.


World distribution(GBIF)

Boreo-temperate, northern hemisphere. European records concentrated in Finland, Sweden Norway, Denmark, Germany, Britain and Ireland with scattered records from other central, western and eastern European countries. Records also from Japan. A concentration of records also from both the north-east and north-west coasts of 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

In Ireland, as in Britain, this is a scarce / rare plant overall.

Sources: Parnell J., Curtis T., 2012; Page C.N., 1997.

Recent (2011) findings by the National Botanic Gardens as part of their 'Conservation and monitoring of legally protected fern allies in Ireland'  suggest that for Lycopodiella inundatum some historic populations are no longer extant.

Lycopodiella inundata has historic records concentrated in the west of Connacht and south west of Munster, records elsewhere on the island few and scattered.

Temporal change

Records submitted to Data Centre in 2021

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 Lycopodiella inundata 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



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.

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.

Lansdown, R.V. 2014. Lycopodiella inundata. The IUCN Red List of Threatened Species. Version 2014.2. <>. Downloaded on 12 November 2014.

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.

Page C.N.,(1997). The Ferns of Britain and Ireland, Secon Edition . Cambridge University Press, Cambridge.

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. <>. Downloaded on 12 November 2014.