Myosotis oreophila

Myosotis oreophila
flowering plant of Myosotis oreophila
Conservation status
Nationally Critical (NZ TCS) [1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Asterids
Order:	Boraginales
Family:	Boraginaceae
Genus:	Myosotis
Species:	M. oreophila
Binomial name
Myosotis oreophila Petrie [2]

Myosotis oreophila is a species of flowering plant in the family Boraginaceae, endemic to the South Island of New Zealand. Donald Petrie described the species in 1896. Plants of this species of forget-me-not are perennial rosettes with ebracteate inflorescences and white corollas with stamens that are partially exserted.

Taxonomy and etymology

Myosotis orephila Petrie is in the plant family Boraginaceae. ^[3] The species was originally described in 1896 by Donald Petrie. ^{[4] [2]} The most recent treatment of this species was done by Lucy B. Moore in the Flora of New Zealand. ^[4]

The original specimens (type material) of Myosotis oreophila were collected by New Zealand Petrie from Mt Ida, Otago, New Zealand and are lodged at the herbarium WELT at the Museum of New Zealand Te Papa Tongarewa (e.g. WELT SP002393/A and SP002393/B). ^{[4] [5] [6]}

Myosotis oreophila can be distinguished from almost all other species of southern hemisphere Myosotis by hairs mixed with antrorse (forward-facing) hairs on the upper side of the leaves. ^{[4] [7]} The only other species that has this trait is M. venticola. ^[2]

Phylogeny

The sole individual sampled of Myosotis oreophila was shown to be included in the southern hemisphere lineage of Myosotis in phylogenetic analyses of standard DNA sequencing markers (nuclear ribosomal DNA and chloroplast DNA regions) of New Zealand Myosotis. ^[8] Within the southern hemisphere lineage, species relationships were not well resolved. ^{[9] [8]}

Description

Myosotis oreophila plants are rosettes. The rosette leaves have long petioles that are about as long the leaf blades and difficult to distinguish from them. The rosette leaves are up to 40 mm long by 10 mm wide, linear-spathulate, widest at or above the middle, with an obtuse, apiculate apex. The upper surface of the leaf is uniformly and densely covered in appressed antrorse (forward-facing) hairs mixed with retrorse (backward-facing) hairs, whereas the lower surface is uniformly and sparsely covered in appressed and mostly retrorse hairs. Each rosette has few ascending to erect, ebracteate inflorescences that are up to 70 mm long. The cauline leaves are similar to the rosette leaves, but are smaller, become smaller toward the top of the inflorescence, linear-oblong, and subacute. The flowers are several per inflorescence, and each is borne on a short pedicel, without a bract. The calyx is 6–9 mm long at flowering and fruiting, lobed to less than one-half of its length, and with many hairs, some of which are retrorse near the base and others hooked. The corolla is white, with a cylindrical tube, and small scales alternating with the petals. The anthers are partially exserted. The nutlets are 1.8–2.4 × 1.0–1.2 mm. ^{[4] [3]}

Rocky habitat with flowering individuals

The pollen of Myosotis oreophila is unknown.

The chromosome number of M. oreophila is unknown.

Flowering December–January; fruiting January–April. ^{[4] [3]}

Distribution and habitat

Myosotisoreophila is a forget-me-not that is found in rocky, high-elevation fellfield habitats in Central Otago in the South Island of New Zealand. ^{[4] [3]} It is rare and localised to one or few known populations. ^{[10] [11]}

Conservation status

Myosotis oreophila is listed as Threatened - Nationally Critical with the qualifiers "EF" (Extreme Fluctuations), "St" (Stable), and "Sp" (Sparse) on the most recent assessment (2017–2018) under the New Zealand Threatened Classification system for plants. ^[1]

Gallery

• 
  Flowers
• 
  Close up of rosette leaves
• 
  Close up of flowers with exserted anthers
• 
  Flowering plant

References

1. Lange, Peter J. de; Rolfe, Jeremy R.; Barkla, John W.; Courtney, Shannel P.; Champion, Paul D.; Perrie, Leon R.; Beadel, Sarah M.; Ford, Kerry A.; Breitwieser, Ilse; Schönberger, Ines; Hindmarsh-Walls, Rowan (May 2018). "Conservation status of New Zealand indigenous vascular plants, 2017" (PDF). New Zealand Threat Classification Series. 22: 45. OCLC   1041649797.
2. Petrie, Donald (1 January 1896). "Descriptions of three new native plants". Transactions and Proceedings of the Royal Society of New Zealand. 28: 538–539.
3. "Myosotis oreophila". New Zealand Plant Conservation Network. Retrieved 1 August 2023.
4. Moore, L.B. "Boraginaceae. In 'Flora of New Zealand'. (Ed. HH Allan) Vol. 1, pp. 806–833". (Government Printer: Wellington, New Zealand) floraseries.landcareresearch.co.nz. Retrieved 27 April 2022.
5. "Type of Myosotis oreophila WELT SP002393/A | Collections Online - Museum of New Zealand Te Papa Tongarewa". collections.tepapa.govt.nz. Retrieved 1 August 2023.
6. "Type of Myosotis oreophila WELT SP002393/B | Collections Online - Museum of New Zealand Te Papa Tongarewa". collections.tepapa.govt.nz. Retrieved 1 August 2023.
7. Meudt, Heidi; Prebble, Jessica (1 January 2022). "Morphological analyses support recognition of three new threatened species of bracteate–prostrate Myosotis (Boraginaceae) endemic to the South Island of Aotearoa New Zealand". Australian Systematic Botany. 35 (5): 364–394. doi:10.1071/SB22012.
8. Meudt, Heidi; Prebble, Jessica; Lehnebach, Carlos A. (7 November 2014). "Native New Zealand forget-me-nots (Myosotis, Boraginaceae) comprise a Pleistocene species radiation with very low genetic divergence". Plant Systematics and Evolution. 301 (5): 1455–1471. doi:10.1007/S00606-014-1166-X.
9. Richard Winkworth; Jürke Grau; Alastair Robertson; Peter Lockhart (1 August 2002). "The origins and evolution of the genus Myosotis L. (Boraginaceae)". Molecular Phylogenetics and Evolution . 24 (2): 180–193. doi:10.1016/S1055-7903(02)00210-5. ISSN   1055-7903. PMID   12144755. Wikidata   Q30707919.
10. Dickinson, Katharine; Kelly, Dave; Mark, Alan; WELLS, GUDRUN; CLAYTON, RICHARD (1 April 2007). "What limits a rare alpine plant species? Comparative demography of three endemic species of Myosotis (Boraginaceae)" . Austral Ecology. 32 (2): 155–168. doi:10.1111/J.1442-9993.2006.01704.X.
11. Stanley, Rebecca J.; Dickinson, Katharine; Mark, Alan (1 January 1998). "Demography of a Rare Endemic Myosotis: Boom and Bust in the High-Alpine Zone of Southern New Zealand". Arctic and Alpine Research. 30 (3): 227–240.

External links

• Myosotis oreophila occurrence data from Australasian Virtual Herbarium