Carmichaelia nana
Common names
dwarf broom, dwarf carmichaelia
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Trees & Shrubs - Dicotyledons
Simplified description
Hard cushions of short tightly packed green leafless twigs. Twigs flattened, 1.5–2.5mm wide, yellowish to reddish. Flowers small, purple, inconspicuous at the tip of twigs. Fruit a small dry pod containing 1–3 hard yellowish seeds and which only partly opens.
Flower colours
Violet/Purple, White
Detailed description
Dwarf, spreading shrub, 20–60 mm tall, 0.5 m wide, usually forming a dense mat of cladodes. Branches short, stout, often below ground level, 10–20 mm diameter. Cladodes linear, striate, compressed, usually erect and crowded, green or yellow-green, often hairy when young, glabrous at maturity, 10.0–50.0 × 1.5–2.5 mm; apex subacute, yellow, yellow-green, or red; leaf nodes 2–7. Leaves simple, obovate to broad-oblanceolate, fleshy, green, only occasionally present on seedlings and absent on adults, 4–5 × 1–2 mm; both surfaces hairy; apex retuse to obtuse; base cuneate; margins hairy; petiole glabrous or hairy, c. 1 mm long. Leaves on cladodes reduced to a scale, narrow to broad-triangular, glabrous, < 1 mm long; apex subacute to obtuse. Stipules free, c. 0.50 × c. 0.25 mm; margin hairy. Inflorescence a raceme, 1–2 per node, each with 1–4 flowers. Peduncle glabrous to hairy, green, 3–4 mm long. Bracts triangular, glabrous, pale green becoming membranous, < 0.5 mm long; apex subacute to obtuse; margin hairy. Pedicel glabrous or hairy, pale green, 1–2 mm long. Bracteoles on pedicel, glabrous, < 0.5 mm long; apex acute; margin hairy. Calyx campanulate, green to green-yellow, 1.5–2.0 × 1.0–2.0 mm; inner surface glabrous; outer surface glabrous to sparsely hairy. Calyx lobes narrow- to broad-triangular, c. 0.5 mm long; apex subacute to obtuse, red to green; margin hairy or occasionally glabrous. Bud pale purple. Standard obovate, spreading horizontally above wings and keel, 4.5–6.5 × 4–5 mm; upper surface purple, with white margins and purple-veined; lower surface white, purple-veined; apex retuse; margin recurved; claw pale green, c. 1.25 mm long. Wings oblong, longer than keel, 3.50–5.50 × c. 1.25 mm; both surfaces white, flushed purple, sometimes purple-veined; auricle rounded, pale green or white, < 0.25 mm long; claw pale green, c. 2 mm long. Keel 4.50–5.00 × c. 1.25 mm; distal area of both surfaces purple, white in central and proximal areas, sometimes purple-veined; auricle rounded, pale green or white, c. 0.25 mm long; claw pale green, c. 2 mm long. Stamens 3.5–5.0 mm long; lower filaments connate for c. ½ length and with outside filaments free for 1.75–2.25 mm. Pistil exserted beyond stamens, 4–6 mm long; style glabrous or with few scattered hairs on adaxial surface; ovules 4–8. Pod short- or broad-oblong, occasionally broad-elliptic or ovate, laterally compressed, brown, black, or yellow-green, one valve partially dehiscent from upper replum, other valve usually indehiscent or only weakly dehiscent, 5.0–7.0 × 4.5–5.5 mm; beak in a central apical position, straight or slightly curved, 1–3 mm long. Seeds oblong-reniform, 1–3 per pod, yellow, yellow-green, green, or black, occasionally with green or black mottling, 2.50–3.00 × 1.75–2.00 mm.
Similar taxa
Distinguished from all other dwarf Carmichaelia species by its smaller flowers, usually short-oblong or broad-oblong pod, and having one valve partially dehiscent from the upper replum.
Distribution
Endemic. New Zealand: North Island (Central Volcanic Plateau and adjacent ranges), South Island (Marlborough, Canterbury, and Otago).
Habitat
Lowland to alpine. Inhabiting stable but unconsolidated alluvial river beds and eyots, river terraces, moraines, shingle slopes, lahar mounds and inland volcanogenic dunes
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – these interim threat classification statuses has not been assessed by the NZTCS panel.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | Threatened – Nationally Vulnerable | Qualifiers: DPR, DPS, DPT, RF
Detailed taxonomy
Family
Fabaceae
Synonyms
Carmichaelia ensyii Kirk; Carmichaelia ensyii var. ambigua G.Simpson; Carmichaelia enysii var. orbiculata (Col.) Kirk; Carmichaelia orbiculata Col.; Carmichaelia australis var. nana Hook.f.
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
November–February
Fruiting
January–May
Control techniques
Seeds are possibly dispersed by wind and granivory (Thorsen et al., 2009).
Propagation technique
Easily grown from seed and hardwood cuttings. An attractive species that deserves wider cultivation. Dislikes humidity.
Other information
Etymology
carmichaelia: After Carmichael, a botanist
nana: Small
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.
CARNAN
Chromosome number
2n = 32
Previous conservation statuses
2017 | Threatened – Nationally Vulnerable | Qualifiers: DP
2012 | At Risk – Declining | Qualifiers: DP
2009 | Not Threatened
2004 | Not Threatened
Referencing and citations
References and further reading
Heenan PB. 1995. A taxonomic revision of Carmichaelia (Fabaceae - Galegeae) in New Zealand (part I). New Zealand Journal of Botany 33(4): 455–475. https://doi.org/10.1080/0028825X.1995.10410618.
Thorsen MJ, Dickinson KJM, Seddon PJ. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285–309. https://doi.org/10.1016/j.ppees.2009.06.001.
Attribution
Description adapted from Heenan (1995)