Apium prostratum subsp. prostratum var. filiforme


Apium: The ancient Latin name for celery or parsley. Believed to be derived from the Celtic word apon 'ditch' and refers to the watery habitat of many species
prostratum: prostrate
filiforme: From the Latin filum 'thread' and forma 'shape', meaning thread-shaped

Common Name(s)

New Zealand celery

Current Conservation Status

2012 - Not Threatened

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2009 - Not Threatened
2004 - Not Threatened


Apium prostratum subsp. prostratum var. filiforme (A.Rich.) Kirk



Flora Category

Vascular - Native

NVS Species 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.

Structural Class

Dicotyledonous Herbs other than Composites


Petroselinum prostratum (Labill ex Vent.) DC., Helosciadium prostratum (Labill. ex Vent.) Bunge in Lehm., Petroselinum filiforme A.Rich., Apium filiforme (A.Rich.) Hook., Apium australe auct. non Pet.-Thou.


Indigenous. In New Zealand known from the Kermadec, Three Kings, North, South, Stewart and Antipodes Islands. Also in eastern Australia as far north as Brisbane and along the whole coastline of southern Australia and Tasmania


Coastal and lowland. Very rarely montane. Common on rock ledges, boulder falls, cliff faces, within petrel scrub on damp seepages, in peaty turf, saltmarshes, within estuaries on mud banks, around brackish ponds, and lagoons. Also found in freshwater systems such as around lake and tarn sides, along streams and rivers and in wet hollows occasionally well inland, and sometimes at considerable elevations.


Perennial, glabrous, prostrate herb. Stems prostrate, sprawling, often ascending though surrounding vegetation, not rooting at nodes; 0.3-1.2 m long, up to 6 mm diam. Leaves dark green to yellow green, basal ones on long, slender petioles up to 500 mm (usually much less); pinnately 3-foliolate to 1-2-pinnate; segments ovate, obovate to cuneate, deeply incised and toothed; Leaves opposite compound umbels similar though with leaflets divided, elliptic, ovate, obovate or more or less cuneate, primary segments elliptic, ovate, obovate, or more or less cuneate in outline, with overall length 0.5-3x the greatest breadth, ultimate segments to tertiary order 8-74 per leaf. Inflorescences in compound umbels, sessile or pedunculate; peduncle usually present. 2-20 mm x 1-3 mm, usually ebracteate, sometimes one present present, this usually shedding early in umbel maturation. Rays 10-20, 0.4-8 mm long. Petals off-white to cream, with yellow-brown mid vein, ovate 0.75-1.5 x 0.5-1.0 mm, constricted at base, apex acute. Stamens about length of petals, filaments pale yellow to cream; anthers whitre or pale yellow, 0.3-0.4 x 0.3-0.4 mm. Ovary glabrous, stylopodium disciform; style 0.25-0.40 mm. Mericarps (1.5-)2.0-2.7 mm long, ovate to ovate-oblong, apex narrowed to persistent withered calyx teeth and style remnant, base broad and rounded to weakly cordate; ribs prominent, broad, rounded and spongy. Surface dull yellow to pale brown.

Similar Taxa

Garden celery (Apium graveolens) is occasionally found wild and can look very similar. It is an erect, biennial herb with filiform ribs on the mericarps (fruits). Water celery (Apium nodiflorum (L.) Lagasca is a species of freshwater systems where it grows along drains, river, stream, lake and pond margins. Its umbels are always bracteolate, and the stems root freely at the nodes. The Chatham Island endemic A. prostratum subsp. denticulatum P.S.Short, differs by its allopatric distirbution, and by the leaves opposite the umbels up to 60 mm long; primary leaflets 3-5, leaflets or segments markedly denticulate with 6-36 secondary segments per leaflet only.


August - March

Flower Colours



September - July

Propagation Technique

Easily grown from fresh seed and whole plants. beign edible and pelasant tatsing it could be more widely used as a substitute for celery (Apium graveolens L.).


Not Threatened

Chromosome No.

2n = 22

Endemic Taxon


Endemic Genus


Endemic Family


Life Cycle and Dispersal

Corky mericarps are dispersed by water (Thorsen et al., 2009).

Notes on taxonomy

New Zealand plants of Apium prostratum are extremely variable and at least one entity currently included within var. filiforme is apaprently unnamed. These plants are usually found on muddy ground within saltmarshes, in brackish ponds, and sometimes inland around lakes, stream and river sides. The variant has very slender leaves, often purplish petioles and distinct white piliferous to markedly apiculate leaf apices. It has long been known under the tag names White Denticles and Slender. It warrants more study.

References and further reading

Johnson, A. T., Smith, H. A. (1972). Plant Names Simplified: Their pronunciation, derivation and meaning. Landsman Bookshop Ltd: Buckenhill, UK.

Thorsen, M. J.; Dickinson, K. J. M.; Seddon, P. J. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 2009 Vol. 11 No. 4 pp. 285-309

This page last updated on 4 Dec 2014