New Zealand Plant Conservation Network
  • Member login
  • Join
Facebook
  • Home
  • Flora
    • Flora species
    • Vascular
    • Non Vascular
    • Plant identification
    • Fungi
    • Make your own book
    • Quiz
  • Threats
    • Exotic Plants (Weeds)
    • Pest Animals
    • Other threats
  • Ecosystems
    • Plant communities
    • Ecosystem services
    • Novel ecosystems
  • Publications
    • Documents
    • Newsletter
    • Plant lists
    • Botanical Society journals
    • NZPCN publications
  • Conservation
    • Seedbank
    • Training
    • Restoration
    • Monitoring
    • Habitat protection
    • Funding
    • Botanic gardens
  • NZPCN
    • News
    • Trilepidea newsletter
    • Events
    • Members
    • Council members
    • Awards
    • Shop
    • Donate
    • Favourite Plant
    • Why join NZPCN?
    • Join
  • Help
    • FAQ
    • Query
    • Glossary
  • Contact us

Search flora

You are here:
  1. Home
  2. Flora
  3. Flora species
  4. Althenia bilocularis

Althenia bilocularis

Download PDF Comment on factsheet

NZPCN members can select up to 20 plant species and automatically create a full colour, fully illustrated A4 book describing them (in PDF format).

  • Find out more...
  • Join NZPCN...
iNaturalist NZ View observations Flora of NZ Click here to view Donate Support NZPCN

Synonyms

Lepilaena bilocularis Kirk

Family

Potamogetonaceae

Authority

Althenia bilocularis (Kirk) Cockayne

Flora category

Vascular – Native

Endemic taxon

No

Endemic genus

No

Endemic family

No

Structural class

Herbs - Monocots

NVS code

The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.

LEPBIL

Current conservation status

  • Conservation status of New Zealand indigenous vascular plants, 2017

The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants. Authors: By Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley.

2012 | Threatened – Nationally Vulnerable | Qualifiers: RR, SO, Sp

Previous conservation statuses

2009 | At Risk – Naturally Uncommon | Qualifiers: SO

2004 | Sparse

Distribution

Indigenous. Known from North, South and Chatham Islands. Also present in Australia.

Habitat

Aquatic herb of lakes, brackish water, or slow-flowing rivers. Usually found in shallow fresh water habitats not far from the coast.

Features

Annual, summer-green, submerged, rhizomatous herb forming small patches. Stems up to 20 cm long, thread-like, usually unbranched. Internodes 1-4 cm long. Leaves regularly alternate, leaf-base at first sheathing stem, to 4 mm long, becoming fibrous with age, leaf-blade 2.5-3.5 x 1 mm, entire, 1- or 3- nerved, with nerves extending to the squarely truncate tip. Flower enclosed within leaf-bases. Both sexes in separate positions on the same plant. Male on small 5 mm stalk (pedicel), stamen solitary, anther 2 x 0.6 mm, sickle-shaped, with 2 pollen sacs. Female shortly stalked (pedicellate), perianth-segments narrow-oblong, lacerate, 1.5 x 0.5 mm. Carpels 3(-4), style narrower than ovary, stigma funnel-shaped with long feathery margins. Seed (achene) 1.5-2 x 0.5 mm., asymmetrically oblong, yellow, smooth, narrowing above to style remnant c. 1 mm long.

Similar taxa

Althenia is most likely to be confused with Zannichellia palustris which is a superficially similar indigenous aquatic herb of much the same habitats. Zannichellia differs from Althenia by its much-branched floating habit, in having leaves arranged in false whorls of 3-4, and by the flowers arranged together within the sheathing bracts. Submerged plants of Schoenus maschalinus (Cyperaceae) are also superficially similar, but these are much branched, and will not flower when submerged.

Flowering

Flowers can be present throughout the year

Fruiting

Fruit can be present throughout the year

Propagation technique

No information available.

Threats

As the result of field surveys it is clear that Althenia bilocularis is biologically sparse in its distribution. In the northern part of its range it seems to have been especially uncommon and there more than anywhere else is where it has undergone some range contraction. However, that loss is insufficient to justify its listing as Threatened.

Taxonomic Notes

Althenia bilocularis was initially placed in the genus Lepilaena, as L. bilocularis by Thomas Kirk who discovered it and described it (Kirk 1896). Later Cockayne (1927) placed Lepilaena bilocularis in Althenia, a decision that was not followed by Moore & Edgar (1970). Subsequently using a combination of molecular and morphological data Ito et al. (2016) confirmed the opinion of Cockayne (1927) and resurrected his combination in Althenia and this is followed here.

Attribution

Fact Sheet prepared for NZPCN by P.J. de Lange 14 April 2007: Description adapted from Moore and Edgar (1970).

References and further reading

Cockayne, L.C. in Speight, R., Wall, A. & Laing, R.M. (ed.) 1927: Ecological botany of the Canterbury Plains. Natural History of Canterbury: 126

Ito, Y.; Tanaka, N.; García-Murillo, P.; Muasya, A.M. 2016: A new delimitation of the Afro-Eurasian plant genus Althenia to include its Australasian relative, Lepilaena (Potamogetonaceae)–evidence from DNA and morphological data. Molecular Phylogenetics and Evolution 98: 261-270.

Kirk, T. 1896: Art. LII: Notes on Certain Veronicas, and descriptions of new species. Transactions and Proceedings of the New Zealand Institute 28: 500.

Moore, L.B.; Edgar, E. 1970: Flora of New Zealand. Vol. II. Government Printer, Wellington.

NZPCN Fact Sheet citation

Please cite as: de Lange, P.J. (Year at time of access): Althenia bilocularis Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/althenia-bilocularis/ (Date website was queried)

▲ Back to top
  • Home
  • Flora
  • Threats
  • Ecosystems
  • Publications
  • Conservation
  • NZPCN
  • Help
  • Contact us

© 2022 New Zealand Plant Conservation Network • Website by RS

Coastlands Plant Nursery Wildlands

Website sponsor

  • Home
  • Flora
    • Flora species
    • Vascular
      • Ferns
        • King fern
        • True ferns
        • Adder's tongue ferns
        • Fork ferns and whisk ferns
        • Horsetails
      • Conifers
        • Celery pines
        • Kauri
        • Podocarps
          • Podocarpus
          • Dacrydium
          • Prumnopitys
          • Dacrycarpus
          • Halocarpus
          • Lepidothamnus
          • Manoao
        • Cypress
      • Flowering plants
        • Parasites
          • Leafy mistletoes
          • Pygmy mistletoes
            • Korthalsella flowers
            • Korthalsella hosts
            • Dispersal of Korthalsella
            • Associates of Korthalsella
          • Root parasites
          • Saprophytes
        • Epiphytes
          • NZ
            • Typical
            • Occasional
            • Hemi-epiphytes
            • Ephemeral
            • NZ list
        • Monocots
          • Orchids
            • Structure
          • Grasses
        • Dicots
          • Hebes
          • Kowhai
          • Coprosma
          • Beech
          • Rata
        • Carnivorous
        • Deciduous plants
        • Aquatic plants
      • Poisonous plants
        • Poisons in the garden
        • Poisonous food plants
        • Poisonous natives
      • Threatened plant lists
      • What's a vascular plant?
      • Club mosses
    • Non Vascular
      • Bryophytes
        • Liverworts
        • Mosses
        • Hornworts
      • Algae
        • Seaweeds
      • Lichens
    • Plant identification
      • Written descriptions
      • Experts
      • Plant keys
        • Key to parasitic plant genera
      • Collecting plants
        • Should I collect
        • Choosing a specimen
        • Field notes
        • Fresh plant material
        • Pressing and drying
        • Mounting specimens
        • Labelling specimens
    • Fungi
    • Make your own book
    • Quiz
  • Threats
    • Exotic Plants (Weeds)
      • Unwanted organisms
      • DOC weeds
      • Plant me instead
      • Pest Plant Accord
    • Pest Animals
      • Mammals
        • Mustelids
        • Rodents
        • Ungulates
        • Possums
      • Fish
      • Insects
    • Other threats
      • Natural events
        • Insects
      • Human induced
        • Habitat loss
        • Collection
        • Climate change
  • Ecosystems
    • Plant communities
      • Dunes
        • Volcanic
        • Coastal
          • Threats
          • Common species
          • Research on dunes
          • Pingao research
          • What you can do
      • Wetlands
        • Estuaries
          • Common estuarine species
          • Research on estuaries
        • Ephemeral
        • Restiad peat bogs
      • Forests
        • Kauri-podocarp-broadleaved
        • Podocarp broadleaved
        • Beech
      • Scrub/shrublands
        • Geothermal
          • Distribution of geothermal vegetation
          • Geothermal plants
          • Geothermal vegetation types
          • Threats to geothermal vegetation
        • Frost flat/hollow
        • Manuka fens
        • Gumlands
      • Grasslands
        • Tussock grasslands
      • Bare ground
        • Braided rivers
        • Alpine
        • Cliff
        • Scree and boulderfields
        • Shingle beaches
      • Herbfields
        • Saltpan
    • Ecosystem services
    • Novel ecosystems
  • Publications
    • Documents
    • Newsletter
    • Plant lists
      • Plant lists by region
      • National plant lists
      • How to prepare a plant list
    • Botanical Society journals
    • NZPCN publications
  • Conservation
    • Seedbank
      • Project 1 - Pohutukawa, Rata and Myrtaceae
      • Project 2 - Alpine flora and the Forget-Me-Nots
      • Project 3 - Kowhai and its relatives
      • Project 4 - Podocarps and trees of the forest
    • Training
      • Module 1: Plant life
      • Module 2: Covenants
      • Module 3: Propagation
      • Module 4: Wetlands
      • Pilot course 2006
    • Restoration
      • Gardening
        • Being weed wise
        • Garden plants
          • Trees and shrubs
          • Broad-leaved herbs
          • Grass-like herbs
          • Climbers
          • Ferns
        • Attracting wildlife
        • Planting for lizards
          • Rules
      • Species recovery
        • Plant translocations
      • Ecological restoration
        • Case studies
          • Tavora Reserve
          • Waiwhakareke
      • Revegetation
      • Eco-sourcing
      • Find a restoration group
    • Monitoring
      • Number count
        • Number count method
        • Pros and cons of number counts
        • Data analysis and interpretation
      • Presence/absence surveys
        • Presence/absence survey methods
        • Pros and cons of presence/absence surveys
        • Data analysis and interpretation
      • Mapping spatial extent
        • Spatial extent mapping methods
        • Pros and cons of spatial extent mapping
        • Data analysis and interpretation
      • Photo points
        • Photo point guidelines
    • Habitat protection
      • Legal protection
        • Nga Whenua Rahui
        • QEII covenants
        • DOC Covenants
      • Animal pest control
      • Weed control
      • Fencing
    • Funding
    • Botanic gardens
  • NZPCN
    • News
    • Trilepidea newsletter
    • Events
      • Conference 2022
        • 2022 conference postponement
        • 2022 conference field trips
        • 2022 conference workshops
        • Code of conduct
        • COVID-19 information
        • 2022 conference sponsors
        • Abstract and poster submission
        • 2022 Conference venue and accommodation
      • Conference 2019
      • Conference 2017
      • Conference 2015
        • Speakers
        • Workshops
        • Field trips
        • Charity auction
      • Conference 2013
        • Speakers
        • Timetable
    • Members
    • Council members
      • NZPCN council member profiles
      • Council 2013
      • Council 2012
      • Council 2011
      • Council 2010
      • Council 2009
      • Council 2008
      • Council 2007
      • Council 2006
      • Council 2005
      • Council 2004
      • Council 2003
    • Awards
      • NZPCN Awards
        • 2019
        • 2018
        • 2017
        • 2016
        • 2015
        • 2014
        • 2013
        • 2012
        • 2011
        • 2010
        • 2009
        • 2008
        • 2007
        • 2006
        • 2005
      • David Given Scholarship
        • David Given Scholarship Recipients
    • Shop
    • Donate
    • Favourite Plant
    • Why join NZPCN?
    • Join
  • Help
    • FAQ
      • Joining the Network
      • The Network
      • Network website
      • New Zealand plants
      • The law
      • Your discoveries
    • Query
    • Glossary
  • Contact us