Rytidosperma biannulare
| Rytidosperma biannulare | |
|---|---|
 | |
| Te Papa herbarium specimen from Northland, New Zealand | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Embryophytes |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Monocots |
| Clade: | Commelinids |
| Order: | Poales |
| Family: | Poaceae |
| Genus: | Rytidosperma |
| Species: | R. biannulare |
| Binomial name | |
| Rytidosperma biannulare (Zotov) Connor & Edgar[2] | |
| Synonyms | |
|
Notodanthonia biannularis Zotov[3], Austrodanthonia biannularis (Zotov) H.P.Linder | |
Rytidosperma biannulare is a species of true grass in the subfamily Danthonioideae. It is endemic to New Zealand and is also naturalised in Hawaii.
Description
Leaves are green and narrow, longer than the culms and forming tussocks. Culms hairless and reaching 85 cm tall. Panicle dense and 10-20 cm long, with short branches and few to many spikelets. Spikelets with 6 or 7 flowers and exserted, fine awns.[2]
The ploidy level of R. biannulare was measured to be 4x.[4]
close-up of floret
close-up showing tufts of hairs at apices of leaf sheaths
close-up of floret
Taxonomy
Rytidosperma biannulare is a species in the grass family (Poaceae).[5]The species was originally described as Notodanthonia biannularis in 1963 by Russian-New Zealand botanist Victor Zotov.[3] The holotype specimen was collected in Waitangi Forest, Northland, New Zealand by Zotov in 1953 and is housed at the Allan Herbarium at the New Zealand Institute for BioEconomy Science in Lincoln, New Zealand (CHR 85021).[3][2][6]
In 1979, New Zealand grass specialists Henry Connor and Elizabeth Edgar moved all New Zealand species of Notodanthonia to the genus Rytidosperma, which is the correct name for this genus of southern hemisphere grasses in the subfamily Danthonioideae.[7][2][8]
Distribution and habitat
Rytidosperma biannulare is endemic to New Zealand, and found on both the North Island and the South Island. In the North Island, it is mainly found in northern areas (Northland and Auckland), but has been recorded as far south as Wellington, and in the South Island it is also found in northern areas (Nelson and Marlborough).[5][2]
In the Auckland area, Rytidosperma biannulare is found on roadsides and in gumland scrub and roadside where the soil has low fertility, together with other grasses Dichelachne crinita, Dichelachne inaequiglumis and Deyeuxia quadriseta.[9]
R. biannulare is also naturalised in Hawaii[10] (on Moloka‘i and Maui) and is currently the only Rytidosperma species known from West Maui, but overlaps with R. gracile is East Maui. It may have arrived within 12 accessions of Rytidosperma imported by the Hawaii Agricultural Experiment Station (HAES) from 1913–1937, or in seeds imported accidentally with hay.[11]
Conservation status
The species is listed as Not Threatened in the 2023 New Zealand Threat Classification System classification.[1]
Ecology
The rust fungus Uromyces danthoniae, a species found that grows parasitically on the leaves of several Rytidosperma species in New Zealand and Australia, infects Rytidosperma biannulare. It forms dense clusters of orange-brown aecidia on both surfaces of the leaf.[12]
R. biannulare uses C3 carbon fixation.[10]
References
- 1 2 Peter J. de Lange; Jane Gosden; Shannel P. Courtney; et al. (October 2024). "Conservation status of vascular plants in Aotearoa New Zealand, 2023" (PDF). New Zealand Threat Classification Series. 43: 1–105. ISSN 2324-1713. Wikidata Q130392985.
- 1 2 3 4 5 Connor, H. E.; Edgar, E. (1979). "Rytidosperma Steudel (Notodanthonia Zotov) in New Zealand". New Zealand Journal of Botany. 17 (3): 311–337. doi:10.1080/0028825X.1979.10426906. ISSN 1175-8643.
- 1 2 3 Zotov, V. D. (March 1963). "Synopsis of the grass subfamily Arundinoideae in New Zealand". New Zealand Journal of Botany. 1 (1): 78–136. doi:10.1080/0028825X.1963.10429323. ISSN 0028-825X.
- ↑ B. G. Murray; I. E. Weir; A. R. Ferguson; P. J. de Lange (March 2003). "Variation in DNA C‐value and haploid genome size in New Zealand native grasses". New Zealand Journal of Botany. 41 (1): 63–69. doi:10.1080/0028825x.2003.9512832. ISSN 0028-825X. Wikidata Q141189119.
- 1 2 "Rytidosperma biannulare". New Zealand Plant Conservation Network. Retrieved 2026-08-27.
- ↑ "Holotype of Notodanthonia biannularis Zotov (CHR 85021)". scd.landcareresearch.co.nz. Retrieved 2026-08-27.
- ↑ "Flora of New Zealand | Taxon Profile | Rytidosperma biannulare". www.nzflora.info. Retrieved 2026-06-26.
- ↑ "Rytidosperma biannulare (Zotov) Connor & Edgar | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 2026-08-27.
- ↑ Wilcox, M.D. "Observations on Grasses in the Auckland Region" (PDF). Auckland Botanical Society Newsletter. 55 (1): 1–6.
- 1 2 Curtis C. Daehler; Kevin Faccenda; Elizabeth Aquino Peterson; Kelsey C. Brock; Lucas Berio Fortini (April 2026). "Predicted Range Shifts of Non‐Native Grasses in Response to Climate Change Are Influenced by Photosynthetic Pathway: A Case Study in the Hawaiian Islands". Diversity and Distributions. 32 (4). doi:10.1111/ddi.70190. ISSN 1366-9516. Wikidata Q141189123.
{{cite journal}}: CS1 maint: unflagged free DOI (link) - ↑ Faccenda, Kevin (2025). "Updates to the Hawaiian grass flora: Part 4" (PDF). Records of the Hawaii Biological Survey.
- ↑ McKenzie, E. H. C.; Latch, G. C. M. (July 1980). "Occurrence of Uromyces danthoniae and U. macnabbii , and additions to the graminicolous rust fungi of New Zealand". New Zealand Journal of Agricultural Research. 23 (3): 393–397. Bibcode:1980NZJAR..23..393M. doi:10.1080/00288233.1980.10425373. ISSN 0028-8233.
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