Puccinellia chathamica
Common name
Chatham Islands salt grass
Synonyms
Atropis chathamica Cheeseman; Puccinellia walkeri subsp. chathamica (Cheeseman) Edgar
Family
Poaceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Grasses
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.
PUCCHA
Chromosome number
2n = 42
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) – 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.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – an interim threat classification status has not been assessed by the NZTCS panel.
- Conservation status of New Zealand indigenous vascular plants, 2017 . 2018. 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. Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | At Risk – Naturally Uncommon | Qualifiers: EF, RR
Previous conservation statuses
2012 | At Risk – Naturally Uncommon | Qualifiers: EF, RR
2009 | At Risk – Naturally Uncommon | Qualifiers: DP
2004 | Sparse
Distribution
Endemic. Confined to the Auckland, Campbell and Chatham Islands. On the Chatham Islands it occurs on Chatham, Pitt, South-East and Rabbit Island.
Habitat
Coastal cliffs, clay faces, rocky shores and islets.Usually it is found growing within the zone of heavy salt influence very near the shore, frequently in seepages and mostly out of stock reach.
Detailed description
Erect, densely tufted, glaucous to dark green, pliant but rigidly firm grass 60–500 mm tall. Upper most leaves over topping culms; branching intravaginal. Leaf-sheath light greenish brown, dark brown or purple glabrous, firmly membranous, striate. Ligule 0.6–3 mm, obtuse or truncate, glabrous, entire. Leaf–base 50–300 × 5–10 mm, folded, rarely flat, abaxially glabrous, adaxially finely ribbed, ribs finely scabrid, apex acute, smooth, rarely subobtuse and apiculate. Culm usually hidden by sheaths, internodes glabrous. Panicle usually overtopped by leaves, 20–130 × 6–20 mm, linear-lanceolate, erect, very contracted, dense; branches stiff, smooth, subacute-angled. Spikelets 3–9 mm, 2–5-flowered, glaucous or brown-green. Glumes unequal, narrow lanceolate to elliptic-oblong, subacute; lower 1.5–4.5 mm, 1–3-nerved, elliptic-oblong, usually with a few hairs at base and on nerves near base to about midway. Lemma usually 5-nerved (rarely 7-nerved); apex minutely ciliate-scabrid, obtuse with slightly excurrent midnerve, rarely entire. Palea ≤ lemma, keel scabrid in upper ⅓ rarely slightly ciliate below, reaching only to apex. Rhacilla 0.8–1.8 mm. Anthers 0.6–1.5 mm, purple. Seed 1.5–2.6 × 0.4–0.8 mm, brown or grey-brown.
Manaaki Whenua Online Interactive Key
Similar taxa
Endemic to the Chatham and Auckland Islands where it is the only Puccinellia Parl. present. Herbarium specimens may be distinguished from P. walkeri Kirk and P. antipoda (Petrie) Allan et Jansen by the very narrow, condensed panicle and smooth panicle branches. P. walkeri tends to have a rather open, spreading almost pyramidal inflorescence when mature.
Flowering
Septeber–January
Fruiting
December–May
Propagation technique
Can be grown from fresh seed and rooted pieces. In humid climates such as Auckland it is difficult to maintain and does not flower.
Threats
Sheep, cattle and goats pose the greatest threats to those populations on the two main, and farmed islands of the Chatham Island group, Chatham and Pitt. However, this grass is secure on many of the outer offshore islands of that archipelago, including the remote Forty-fours. Some of the main Chatham Island populations are vulnerable to coastal erosion. On the Auckland Islands its exact status is unknown but recent visits suggest that it is locally common in suitable habitats.
Etymology
puccinellia: After the italian botanist Benedetto Puccinelli (1808 - 1850).
chathamica: From the Chatham Islands
Where To Buy
Not commercially available
Taxonomic Notes
Edgar (1996) treated this species (and P. antipoda) as a subspecies of P. walkeri. Since then further research has elucidated that P. chathamica and P. walkeri have very different chromosome numbers and nrDNA ITS sequences. Subspecies rank therefore is rejected. On the Auckland Islands there is cytological support for the recognition of two taxa within P. chathamica—this needs further study. It is not clear whether Campbell Island plants are P. chathamica s.s. either, and this again needs further study.
Attribution
Description modified from Edgar and Connor (2000).
References and further reading
Edgar E, Connor HE. 2000. Flora of New Zealand. Vol. V. Grasses. Manaaki Whenua Press, Christchurch, NZ. 650 p.