Tuesday 21 May
In the News: First crane egg in the western UK in four centuries
Holly-leaved naiad (Najas marina)
Holly-leaved naiad fact file
- Description
- Biology
- Range
- Habitat
- Status
- Threats
- Conservation
- Find out more
- Glossary
- References
- Print factsheet
Holly-leaved naiad description
| Kingdom | Plantae |
| Phylum | Anthophyta |
| Class | Liliopsida |
| Order | Najadales |
| Family | Najadaceae |
| Genus | Najas (1) |
The holly-leaved naiad (Najas marina) is an aquatic plant (3) that has tough narrow leaves on forked, brittle stems. Both the leaves and the stems have spiky projections; these occur particularly towards the tip of the stem (4). The flowers are highly inconspicuous, and the fruit, which lacks a stalk, is fleshy (2).
- French
- Naja de Marine.
- Size
- Leaf width (including teeth): 1 - 6 mm (2)
- Leaf length: 1.0 - 4.5 cm (2)
- Fruit size: 4.0 - 6.0 x 1.5 - 3.0 mm (2)
More »
Top
Related species
Holly-leaved naiad biology
The holly-leaved naiad occurs as either an annual or a short-lived perennial, and flowers in July and August (3). Male plants were only recently discovered in the UK, and it was previously thought that the plant could reproduce without cross-fertilisation (3).
TopHolly-leaved naiad range
This species is found in the UK in just three of the Norfolk Broads (5). The holly-leaved naiad is also known from both temperate and tropical areas including Europe, Asia, Australia, Africa, and North and Central America (3). In Europe the species is classified as Vulnerable (3).
More »
Species with a similar range
|
You can view distribution information for this species at the National Biodiversity Network Gateway. |
Holly-leaved naiad habitat
The holly-leaved naiad prefers clear, unpolluted water in fens and reedbeds (5), and shows a preference for sheltered areas (3). It typically grows at depths of between 0.5 and 1.5 millimetres (3) often in slightly brackish water (2).
More »
Top
Species found in a similar habitat
Holly-leaved naiad status
The holly-leaved naiad is classified as Least Concern (LC) on the IUCN Red List (1). It is classified as Vulnerable in Great Britain, and is fully protected in the UK by Schedule 8 of the Wildlife and Countryside Act 1981 (3).
Holly-leaved naiad threats
The main threats to the holly-leaved naiad include nutrient enrichment of water bodies following sewage inputs and agricultural run-off, and boat traffic, which causes pollution and turbulence (5).
TopHolly-leaved naiad conservation
The holly-leaved naiad is a UK Biodiversity Action Plan priority species. The Species Action Plan produced to guide the conservation of the species aims to maintain the current populations, and restore the plant to at least five adjoining waterways before the year 2004 (5). All three of the known sites are Sites of Special Scientific Interest (SSSIs), and the Royal Botanic Gardens, Kew are investigating seed-storage techniques suitable for the species (5).
|
The UK Biodiversity Action Plan for this species is available at UK BAP. |
|
|
There may be further information about this species available via the National Biodiversity Network Gateway. |
Authentication
This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk
Glossary
- Annual
- Lives or grows for just one year.
- Brackish
- Slightly salty water.
- Perennial
- Plants that live for at least three seasons; after an initial period they produce flowers once a year.
References
-
IUCN Red List (June, 2011)
http://www.iucnredlist.org/ - Stace, C. (1991) New Flora of the British Isles. Cambridge University Press, Cambridge.
- Wigginton, M.J. (1999) British Red Data Books 1: Vascular Plants. 3rd Edition. JNCC, Peterborough.
- Clapham, A.R., Tutin, T.G. and Moore, D.M. (1987) Flora of the British Isles. 3rd Edition. Cambridge University Press, Cambridge.
-
UK Biodiversity Species Action Plan (November, 2001)
http://www.ukbap.org.uk/
More »Related species
Sign up to our newsletter
Get the latest wild news direct to your inbox.
Get involved
ARKive relies on its media donors to donate photos and videos. Can you help? There are plenty of other ways you can get involved too!
X
Close
Close
Image credit
Holly-leaved naiad underwater
© Willem Kolvoort / naturepl.com
Nature Picture Library
5a Great George Street
Bristol
BS1 5RR
United Kingdom
Tel: +44 (0) 117 911 4675
Fax: +44 (0) 117 911 4699
info@naturepl.com
http://www.naturepl.com
X
Close
Close
Link to this photo
Embed this ARKive thumbnail link by copying and pasting the code below.
Terms of Use - The displayed thumbnail may be used as a link from your website to ARKive's online content for private, scientific, conservation or educational purposes only. It may NOT be used within Apps.
Read more about
X
Close
Close
MyARKive
MyARKive offers the scrapbook feature to signed-up members, allowing you to organize your favourite ARKive images and videos and share them with friends.
X
Close
Close
Terms and Conditions of Use of Materials
Copyright in this website and materials contained on this website (Material) belongs to Wildscreen or its licensors.
Visitors to this website (End Users) are entitled to:
- view the contents of, and Material on, the website;
- download and retain copies of the Material on their personal systems in digital form in low resolution for their own personal use;
- teachers, lecturers and students may incorporate the Material in their educational material (including, but not limited to, their lesson plans, presentations, worksheets and projects) in hard copy and digital format for use within a registered educational establishment, provided that the integrity of the Material is maintained and that copyright ownership and authorship is appropriately acknowledged by the End User.
End Users shall not copy or otherwise extract, alter or manipulate Material other than as permitted in these Terms and Conditions of Use of Materials.
Additional use of flagged material
Green flagged material 
Certain Material on this website (Licence 4 Material) displays a green flag next to the Material and is available for not-for-profit conservation or educational use. This material may be used by End Users, who are individuals or organisations that are in our opinion not-for-profit, for their not-for-profit conservation or not-for-profit educational purposes. Low resolution, watermarked images may be copied from this website by such End Users for such purposes. If you require high resolution or non-watermarked versions of the Material, please contact Wildscreen with details of your proposed use.
Creative commons material
Certain Material on this website has been licensed to Wildscreen under a Creative Commons Licence. These images are clearly marked with the Creative Commons buttons and may be used by End Users only in the way allowed by the specific Creative Commons Licence under which they have been submitted. Please see http://creativecommons.org for details.
Any other use
Please contact the copyright owners directly (copyright and contact details are shown for each media item) to negotiate terms and conditions for any use of Material other than those expressly permitted above. Please note that many of the contributors to ARKive are commercial operators and may request a fee for such use.
Save as permitted above, no person or organisation is permitted to incorporate any copyright material from this website into any other work or publication in any format (this includes but is not limited to: websites, Apps, CDs, DVDs, intranets, extranets, signage, digital communications or on printed materials for external or other distribution). Use of the Material for promotional, administrative or for-profit purposes is not permitted.