Rytidosperma thomsonii
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Grasses
Simplified description
Recognition in the field: a medium stature Rytidosperma with erect culms, crowded dark spikes and florets with very short awn. The hairs on the lemma are only in two tufts on the margin.
Similar taxa
Similar to larger plants of Rytidosperma pumilum (which shares its habitat) which has scattered hairs on the lemma between the tufts and the awn is not visible to the naked eye. Also similar to R. buchananii which has a long bent awn on the floret.
Distribution
Endemic. New Zealand: South Island (east of the main divide south to Otago).
Habitat
A species of dry lowland and montane grassland.
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 | At Risk – Declining | Qualifiers: DPS
Detailed taxonomy
Family
Poaceae
Synonyms
Danthonia thomsonii Buchanan, Triodia thomsonii (Buchanan) Petrie, Notodanthonia thomsonii (Buchanan) Zotov
Taxonomic notes
There is good morphological and cytogenetic evidence that R. thomsonii could be split into at least two species
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Fruiting
January
Other information
Etymology
rytidosperma: Wrinkled seed
thomsonii: After Thomson
Manaaki Whenua Online Interactive Key
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.
RYTTHO
Chromosome number
2n = 24, 48
Previous conservation statuses
2017 | At Risk – Declining | Qualifiers: DP
2012 | Data Deficient
2009 | Data Deficient
2004 | Not Threatened