Crassula ruamahanga
Synonyms
Tillaea acutifolia Kirk, Crassula acutifolia (Kirk) A.P.Druce et D.R.Given non. Crassula acutifolia Lam.; Crassula hunua A.P.Druce; Tillaea pusilla Kirk var. pusilla, Tillaea pusilla var. brevia Kirk, Crassula pusilla A.P.Druce et D.R.Given non C. pusilla Schönland
Family
Crassulaceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Herbs - Dicotyledons other than Composites
Chromosome number
2n = 42,64,70,84,90
Current conservation status
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 | At Risk – Naturally Uncommon | Qualifiers: Sp
Previous conservation statuses
2009 | At Risk – Naturally Uncommon
2004 | Sparse
Distribution
Endemic. Uncommon, known from historic and extant records from Wairoa River near Dargaville south to Stewart Island and including Chatham Island. In the North Island most common in the Wairarapa, and in the South Island on the Southland plains
Habitat
Sea level to lowland (rarely lower montane) (0-500 m a.s.l.). An opportunistic species which can be expected to occur in any suitably damp, open habitat. It has been collected from near estuarine conditions through to leaking pipes in urban centres, gravel foot paths, and bowling green turf. Its favoured habitat seems to be river sides and muddy hollows and pools within lowland alluvial forest.
Features
Perennial herb form small to large diffuse to dense bright green mats. Stems green or pink, prostrate, rooting at nodes, with ascending tips, much-branched. Leaves fused at base, 1.3-8 x 0.4-1.5 mm, 0.2-0.6 mm thick, lanceolate, linear-lanceolate or elliptic lanceolate, flattened or slightly concave above, convex beneath, apex usually sharply acute, shortly acuminate or apiculate, sometimes obtuse. Flowers solitary in leaf axils, scarcely fragrant, stellate, 4-merous, 1.8-2.5 mm diam.; pedicels 0.5-1 mm, scarcelty elongating at fruiting, Calyx lobes 0.8-1 x 0.4-0.6 mm, triangular or triangular-ovate, white or pink-flushed, acute, sharply acute, occasionally obtuse, slightly or much > calyx. Scales 0.5 mm long, cuneate. Follicles smooth. Seed 0.5 mm long.
Similar taxa
Crassula hunua A.P.Druce, from which it is only doubtfully distinct. From that species it is best distinguished by the acute tipped leaves and petals, persistent presence of a leaf apiculus, and generally by the sepal length exceeding the petals. However these characters seem to intergrade with C. hunua.
Flowering
Flowers may be present throughout the year
Flower colours
Red/Pink, White
Fruiting
Flowers may be present throughout the year
Life cycle
Minute follicles are dispersed by wind and water and possiblty also by attachment (Thorsen et al., 2009).
Propagation technique
Easy from rooted pieces, stem cuttings and seed. Can become a troublesome weed in damp soils and shaded sites, but makes an excellent ground cover or lawn on poorly drained soils. Flowers are sweetly scented.
Threats
Competition from other plants. Habitat destruction through heavy stock use, by cattle in particular.
Etymology
crassula: From the Latin crassus ‘thick’, meaning ‘rather thick’
Cultural Use/Importance
Crassula hunua is now included within C. ruamahanga (see: de Lange et al 2007)
Attribution
Fact Sheet by P.J. de Lange 4 May 2005. Description from de Lange et al. (2009).
References and further reading
de Lange, P.J.; Heenan, P.B.; Keeling, D.J.; Murray, B.G.; Smissen, R.; Sykes, W.R. 2008: Biosystematics and Conservation: A Case Study with Two Enigmatic and Uncommon Species of Crassula from New Zealand. Annals of Botany 101: 881-899
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 11: 285-309
Citation
Please cite as: de Lange, P.J. (Year at time of access): Crassula ruamahanga Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/crassula-ruamahanga/ (Date website was queried)