Zostera muelleri subsp. novazelandica


Zostera: girdle or belt
muelleri: Named after Baron Ferdinand von Mueller, 19th century German/Australian botanist and founder of the National Herbarium of Victoria

Common Name(s)

seagrass, eelgrass, nana, Zostera

Current Conservation Status

2012 - At Risk - Declining

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


2012 - SO


Zostera muelleri subsp. novozelandica (Setch.) S.W.L.Jacobs



Flora Category

Vascular - Native

Structural Class

Monocotyledonous Herbs


Z. novazelandica Setch., Zostera muelleri Irmisch.ex Asch.; Zostera muelleri subsp. novaezelandica (Setch.) S.W.L.Jacobs orth. var.


Indigenous. North, South and Stewart Islands. Throughout southern and eastern Australia


Marine. Mostly submerged in estuaries where it is found on intertidal and subtidal flats of sandy mud. Often in channels or deep pools of water


Grass-like plants of mud or sandy-silt shallow marine environments. Rhizomes compressed 1-2 mm diameter, widely creeping, rooting at nodes; internodes 10-20 mm long. Leaf-sheath 20-40 mm long, becoming fibrous with age, the broad membranous margins inflexed and each terminating in an erect rounded auricle; lamina 50-300 x 1-2 mm; primary nerves 3, interstitial nerves 4-6, cross veins usually at more or less regular, long intervals and mostly all extending from the median to marginal nerve, producing a pattern of distinctive long oblongs. Erect stems narrow, flattened, the subfloral peduncular internode 10-60 x 0.6-1.0 mm. Spathe-like sheath 15-25 x 2.0-2.5 mm (folded width), its margins squarely truncate at the apex and its terminating lamina 30-80 x 1.5-2.0 mm. Spadix often shorter than spathe; retinacula usually 3 on each side, broadly obliquely ovate 1.0-1.5 x 1.0 mm and 2.0-2.5 mm apart. Stamens and carpels closely packed, carpels rarely > 6 and anther-sacs about twice their number, all sloping obliquely inwards and upwards. Achene elliptic-oblong, 2.5 x 1.0 mm; seed smooth, yellow.

Similar Taxa

None - plants referred to Z. capricorni in Flora 2 are merely larger forms of the same subspecies. The type of Z. capricorni is Australian and plants matching that type are not found in New Zealand


October - February


January - February

Propagation Technique

Easily grown in saltwater tanks but otherwise difficult. Plants can be easily propagated through division.


Not Threatened. However, due to widespread siltation and increasingly poor water quality eelgrass communities are declining throughout their range.

Chromosome No.

2n = 24

Endemic Taxon


Endemic Genus


Endemic Family


Where To Buy

Not commerically available.


Description adapted from Moore and Edgar (1997).

References and further reading

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

This page last updated on 2 Jul 2016