Myosotis tenuis G.Simpson et J.S.Thomson
Vascular – Native
Herbs - Dicotyledons other than Composites
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.
Current conservation status
The threat classification 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) – more information about this can be found on the NZTCS website 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. Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – a suggested threat classification status has not been assessed by the NZTCS panel.
2017 | At Risk – Naturally Uncommon | Qualifiers: DP, Sp
Previous conservation statuses
2012 | At Risk – Naturally Uncommon | Qualifiers: DP, Sp
2009 | At Risk – Naturally Uncommon | Qualifiers: DP
2004 | Sparse
Endemic. North, South and Stewart Islands. In the North Island apaprently confined to the north-western Ruahine Range. In the South Island locally distributed from Nelson to Southland though apparently absent from Westland, Marlborough and Canterbury. Also on Stewart island. This species is easily overlooked.
Lowland to alpine (0-1400 m a.s.l.). Upper montane to alpine in the North Island, otherwise as stated. Usually on the margins of slow flowing streams, in muddy ground, on the margins of small, ephemeral pools, in wet ground at the bases of tall tussocks, in shaded sites within forests overlying poorly drained alluvium, an din alpine flushes, seepages and cushion bogs.
Decumbent, green or bronze, sprawling to weakly ascending, slender, perennial herb forming roughly circular to assymetrical diffuse patches up to 200 mm diameter. Adventitious roots frequently produced along weakly ascending partially buried or creeping stem, or adventitious roots absent. Lateral branches 1-10 (or more), weak and somewhat flaccid, occasionally producing new rosettes where touching the ground, some branching again and on occasion flowering. Rosette-leaves obvious, or not very obvious due to creeping stem, these 6-12 x 3-6 mm, elliptic to broadly oval, gradually narrowing to slender petioles up to 40 mm long; hairs of lamina short, closely appressed, mostly evenly though sparsely covering upper surface, undersides glabrescent. Flowering branches 20-400 mm long, internodes distinctly longer than leaves; petioles becoming progressively shorter in upper cauline leaves; bracts sub- to sessile; other similar in shape and indument to rosette and basal stem leaves. Inflorescences cymose; cymes elongated, simple or branched, several-flowered, internodes long, flowers solitary, bract opposed or noticeably belwo bract. Pedicels 1-10 mm long in fruit. Calyx 1.5-3.5(-4) mm, lobes > 1/2 calyx length, narrow, acute, hairs short, appressed, evenly though sparsely distributed. Corolla 3-4 mm diameter, white sometimes with a yellow throat; tube 2 mm long, cylindric; lobes 1 x 1 mm, rounded; filaments almost wanting, anthers < 1 mm long, yellow, included within tube; style up to 4 mm long, stigma capitate. Nutlets projecting from short, widely open calyx, 1.2-1.6 x 0.8-0.9 mm, ovate-elliptic to elliptic, apex obtuse, base rounded margins slightly winged.
Recognised by corolla up to 4 mm diameter, more or less concave, narrow lobes; anthers (< 1 mm long) which are included within or just protrude from the floral tube, and very short, scarcely exserted stigma. The calyces are lobed to about half their length, with the lobes spreading and erect in fruit. In this species the calyx hairs are sparse, but evenly distributed, distinctly spreading, and of uniform length, while the indument of the petioles, internodes and pedicels is similar but much longer. Frequently confused with M. spathulata, which is usually a larger plant whose leaf base rapidly narrows to the petiole, bracts (at least lower ones) and leaves are often orbicular with erect hairs on the undersurfaces, and the hairs on the calyx and stems are distinctly erect and sometimes more or less hooked. Furthermore the stigma is clavate rather than capitate. The amount of stigma projection is not a good character for separating these two distinct species.
November - March
November - April
Difficult as tends to be short-lived and does not self-sow very well. Prone to fungal diseases and dislikes humidity. An attractive pot plant for an alpine house.
An apparently naturally uncommon, biological sparse species. It may be threatened in some parts of its range through competition from weeds. Clarification of its conservation status is needed.
Where To Buy
Not commercially available
Fact Sheet prepared for NZPCN by P.J. de Lange 1 February 2008. Description based on Allan (1961).
References and further reading
Allan, H.H. 1961: Flora of New Zealand. Vol. I. Goverment Printer, Wellington.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Myosotis tenericaulis Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/myosotis-tenericaulis/ (Date website was queried)