Biology:Rytidosperma biannulare
| Rytidosperma biannulare | |
|---|---|
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| Te Papa herbarium specimen from Northland, New Zealand | |
Scientific classification 
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| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Monocots |
| Clade: | Commelinids |
| Order: | Poales |
| Family: | Poaceae |
| Genus: | Rytidosperma |
| Species: | R. biannulare
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| Binomial name | |
| Rytidosperma biannulare (Zotov) Connor & Edgar[2]
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| Synonyms[3] | |
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Rytidosperma biannulare is a species of true grass in the subfamily Danthonioideae. It is native to New Zealand and is also naturalised in Hawaii. It is found on both the North and South Islands of New Zealand and on Moloka‘i and Maui Islands of Hawaii. As at 2023, this species was classified as not threatened by the New Zealand Department of Conservation.
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]
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Close-up of floret -
Close-up showing tufts of hairs at apices of leaf sheaths -
Close-up of floret
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 where the soil has low fertility, together with other grasses Dichelachne crinita, Dichelachne inaequiglumis and Deyeuxia quadriseta.[6]
R. biannulare is also naturalised in Hawaii (on Moloka‘i and Maui)[7] 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.[8]
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.[9]
R. biannulare uses C3 carbon fixation.[7]
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][10]
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.[11][2][12]
Etymology
Rytidosperma: 'wrinkled seed' from the Greek 'rhytidos' = wrinkled and 'sperma' = seed[13]
References
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Wikimedia Commons has media related to Rytidosperma biannulare. |
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Wikispecies has information related to Rytidosperma biannulare |
- ↑ 1.0 1.1 The ID "https://www.wikidata.org/wiki/Q130392985%22 is unknown to the system. Please use a valid entity ID.
- ↑ 2.0 2.1 2.2 2.3 2.4 Connor, H. E.; Edgar, E. (1979). "Rytidosperma Steudel (Notodanthonia Zotov) in New Zealand" (in en). New Zealand Journal of Botany 17 (3): 311–337. doi:10.1080/0028825X.1979.10426906. ISSN 1175-8643. Bibcode: 1979NZJB...17..311C. https://onlinelibrary.wiley.com/doi/abs/10.1080/0028825X.1979.10426906.
- ↑ 3.0 3.1 3.2 Zotov, V. D. (March 1963). "Synopsis of the grass subfamily Arundinoideae in New Zealand" (in en). New Zealand Journal of Botany 1 (1): 78–136. doi:10.1080/0028825X.1963.10429323. ISSN 0028-825X. Bibcode: 1963NZJB....1...78Z. https://rsnz.onlinelibrary.wiley.com/doi/10.1080/0028825X.1963.10429323.
- ↑ The ID "https://www.wikidata.org/wiki/Q141189119%22 is unknown to the system. Please use a valid entity ID.
- ↑ 5.0 5.1 "Rytidosperma biannulare" (in en). https://www.nzpcn.org.nz/flora/species/rytidosperma-biannulare/.
- ↑ Wilcox, M.D.. "Observations on Grasses in the Auckland Region". Auckland Botanical Society Newsletter 55 (1): 1–6. https://bts.nzpcn.org.nz/site/assets/files/20434/auck_2000_55_1_1-6.pdf.
- ↑ 7.0 7.1 , Wikidata Q141189123
- ↑ Faccenda, Kevin (2025). "Updates to the Hawaiian grass flora: Part 4". https://hbs.bishopmuseum.org/PUBS-ONLINE/pdf/op163p111-129.pdf.
- ↑ 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" (in en). New Zealand Journal of Agricultural Research 23 (3): 393–397. doi:10.1080/00288233.1980.10425373. ISSN 0028-8233. Bibcode: 1980NZJAR..23..393M. https://rsnz.onlinelibrary.wiley.com/doi/10.1080/00288233.1980.10425373.
- ↑ "Holotype of Notodanthonia biannularis Zotov (CHR 85021)". https://scd.landcareresearch.co.nz/Specimen/CHR%2085021.
- ↑ "Flora of New Zealand | Taxon Profile | Rytidosperma biannulare". https://www.nzflora.info/factsheet/Taxon/Rytidosperma-biannulare.html.
- ↑ "Rytidosperma biannulare (Zotov) Connor & Edgar | Plants of the World Online | Kew Science" (in en). http://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:419793-1.
- ↑ Australian National Botanic Gardens, Parks Australia. "Rytidosperma pallidum, Joycea pallida - Growing Native Plants" (in en). https://www.anbg.gov.au/gnp/interns-2006/joycea-pallida.html.
Wikidata ☰ Q15521533 entry
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