# Myosotis retrorsa

> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Myosotis_retrorsa
> Markdown URL: https://mediated.wiki/source/Myosotis_retrorsa.md
> Source: https://en.wikipedia.org/wiki/Myosotis_retrorsa
> Source revision: 1355381304
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

Species of flowering plant

Myosotis retrorsa Conservation status Naturally Uncommon (NZ TCS)[1] Scientific classification Kingdom: Plantae Clade: Embryophytes Clade: Tracheophytes Clade: Spermatophytes Clade: Angiosperms Clade: Eudicots Clade: Asterids Order: Boraginales Family: Boraginaceae Genus: Myosotis Species: M. retrorsa Binomial name Myosotis retrorsa Meudt, Prebble and Hindm.-Walls[2]

***Myosotis retrorsa*** is a species of [flowering plant](/source/Flowering_plant) in the [family](/source/Family_(taxonomy)) Boraginaceae, [endemic](/source/Endemic_species) to the [South Island](/source/South_Island) of [New Zealand](/source/New_Zealand). Heidi Meudt, Jessica Prebble and Rowan Hindmarsh-Walls described the species. Plants of this species of [forget-me-not](/source/Forget-me-nots) are [perennial](/source/Perennial_plant) with a prostrate habit, bracteate inflorescences, and white corollas.

## Taxonomy and etymology

*Myosotis retrorsa* Meudt et al. is in the plant family [Boraginaceae](/source/Boraginaceae) and was originally described in 2018 by Heid Meudt, Jessica Prebble and Rowan Hindmarsh-Walls.[2][3] It is morphologically most similar to *[M. pulvinaris](/source/Myosotis_pulvinaris)* and *M. lyallii,* other bracteate-prostrate species of *Myosotis.[2]* *Myosotis retrorsa* can be distinguished from all other bracteate-prostrate species by the retrorse trichomes on the underside of the rosette and cauline leaves, and calyx. Its rosette leaf lamina length : width ratio < 1.3 : 1 can distinguish it from several species including *M. lyallii* (but not *M. pulvinaris*). *M. retrorsa* has 1–3 flowers per inflorescence compared to the solitary flowers of *M. pulvinaris* and the larger inflorescences of *M. lyallii*, which have (2–)4–11 flowers.[2]

The type specimen of *Myosotis retrorsa* is lodged at the herbarium (WELT) of the [Museum of New Zealand, Te Papa Tongarewa](/source/Museum_of_New_Zealand_Te_Papa_Tongarewa).[2][4]

The specific epithet, *retrorsa*, is derived from the Latin word *retrorsus* (backward-facing) and is a nod to the characteristic retrorse trichomes on the underside of the rosette leaves.[2]

## Phylogeny

*Myosotis retrorsa* was not included in [phylogenetic](/source/Phylogenetics) analyses of standard DNA sequencing markers ([nuclear ribosomal DNA](/source/Ribosomal_DNA) and [chloroplast DNA](/source/Chloroplast_DNA) regions).[5][6]

Holotype specimen of *Myosotis retrorsa*

## Description

*Myosotis retrorsa* plants are single rosettes that may cluster together into tufts or loose clumps.. The rosette leaves are 7–30 per plant, and have [petioles](/source/Petiole_(botany)) 2–9 mm long. The rosette leaf blades are 4–7 mm long by 1–4 mm wide (length: width ratio 0.8–1.7: 1), narrowly obovate to very broadly obovate, or orbicular, widest at or above the middle, with an [obtuse](/source/Glossary_of_leaf_morphology#obtuse) apex. The upper surface of the leaf is densely covered in flexuous, appressed to patent, antrorse (forward-facing) hairs that are parallel to the mid vein. The lower surface of the leaf is sparsely to densely covered in flexuous, appressed to patent, retrorse (backward-facing) hairs, sometimes mixed with antrorse hairs, that are parallel or angled relative to the mid vein. Each rosette has 2–15 ascending or prostrate, unbranched or branched, bracteate [inflorescences](/source/Inflorescence) that are usually 20–40 cm long. The cauline leaves are similar in size, shape and hairs to the rosette leaves. There can be up to 3 flowers in each inflorescence, each one borne on a short [pedicel](/source/Pedicel_(botany)) and with a cauline leaf. The calyx is 3–6 mm long at flowering and 5–8 mm long at fruiting, lobed to up to half of its length, and densely covered in short, flexuous, appressed to patent, antrorse hairs and some retrorse hairs near the calyx base. The corolla is white and up to 8 mm in diameter, with a cylindrical tube, petals that are broadly obovate and flat, and small yellow scales alternating with the petals. The anthers are partly exserted, with the tips or the upper third only surpassing the scales. The four smooth, shiny, brown to dark brown nutlets are 1.3–2.2 mm long by 0.8–1.2 mm wide and narrowly ovoid to ovoid in shape.[2][3]

*Myosotis retrorsa* showed intraspecific variation for pollen type, with either *M. australis* or *M. uniflora* type pollen.[7][8]

The chromosome number of *M. retrorsa* is unknown.

It flowers and fruits mainly from December to February.[2]

## Gallery

		- Pollen

		- Close up of hairy leaves and calyces

		- Plant just past flowering growing on rock

		- Close-up of flowers

= Distribution and habitat ==

*Myosotis retrorsa* is endemic to the South Island of New Zealand in Otago, Southland and Fiordland from 915 to 1830 m elevation.[2] It is found in subalpine outcrops, crevices, and fellfield ridges and cirques on schist, marble.[2]

## Cultivation

Although not commonly cultivated, plants of *Myosotis retrorsa* have been cultivated at the [Arctic-Alpine Botanic Garden](/source/Arctic%E2%80%93Alpine_Botanic_Garden) in [Tromsø](/source/Troms%C3%B8_(city)), Norway.[9]

## Conservation status

The species is listed as At Risk - Naturally Uncommon in the most recent assessment (2017–2018) of the [New Zealand Threatened Classification](/source/New_Zealand_Threat_Classification_System) for plants. It also has the qualifiers "DP" (Data Poor), and "Sp" (Sparse).[1]

## References

1. ^ [***a***](#cite_ref-NZTCS_1-0) [***b***](#cite_ref-NZTCS_1-1) 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"](https://www.doc.govt.nz/globalassets/documents/science-and-technical/nztcs22entire.pdf) (PDF). *New Zealand Threat Classification Series*. **22**: 1–86. [OCLC](/source/OCLC_(identifier)) [1041649797](https://search.worldcat.org/oclc/1041649797).

1. ^ [***a***](#cite_ref-csiro_2-0) [***b***](#cite_ref-csiro_2-1) [***c***](#cite_ref-csiro_2-2) [***d***](#cite_ref-csiro_2-3) [***e***](#cite_ref-csiro_2-4) [***f***](#cite_ref-csiro_2-5) [***g***](#cite_ref-csiro_2-6) [***h***](#cite_ref-csiro_2-7) [***i***](#cite_ref-csiro_2-8) [***j***](#cite_ref-csiro_2-9) Meudt, Heidi M.; Prebble, Jessica M. (28 February 2018). ["Species limits and taxonomic revision of the bracteate-prostrate group of southern hemisphere forget-me-nots (Myosotis, Boraginaceae), including description of three new species endemic to New Zealand"](https://www.publish.csiro.au/sb/SB17045). *Australian Systematic Botany*. **31** (1): 48–105. [doi](/source/Doi_(identifier)):[10.1071/SB17045](https://doi.org/10.1071%2FSB17045). [ISSN](/source/ISSN_(identifier)) [1446-5701](https://search.worldcat.org/issn/1446-5701). [S2CID](/source/S2CID_(identifier)) [90834744](https://api.semanticscholar.org/CorpusID:90834744).

1. ^ [***a***](#cite_ref-nzpcn_3-0) [***b***](#cite_ref-nzpcn_3-1) ["Myosotis retrorsa"](https://www.nzpcn.org.nz/flora/species/myosotis-retrorsa/). *New Zealand Plant Conservation Network*. Retrieved 10 May 2022.

1. **[^](#cite_ref-4)** ["Myosotis retrorsa"](https://collections.tepapa.govt.nz/object/1534760). *collections.tepapa.govt.nz*. Retrieved 10 May 2022.

1. **[^](#cite_ref-doi_5-0)** Meudt, Heidi M.; Prebble, Jessica M.; Lehnebach, Carlos A. (1 May 2015). ["Native New Zealand forget-me-nots (Myosotis, Boraginaceae) comprise a Pleistocene species radiation with very low genetic divergence"](https://doi.org/10.1007/s00606-014-1166-x). *Plant Systematics and Evolution*. **301** (5): 1455–1471. [doi](/source/Doi_(identifier)):[10.1007/s00606-014-1166-x](https://doi.org/10.1007%2Fs00606-014-1166-x). [ISSN](/source/ISSN_(identifier)) [2199-6881](https://search.worldcat.org/issn/2199-6881). [S2CID](/source/S2CID_(identifier)) [14686750](https://api.semanticscholar.org/CorpusID:14686750).

1. **[^](#cite_ref-6)** Winkworth, Richard C; Grau, Jürke; Robertson, Alastair W; Lockhart, Peter J (1 August 2002). ["The origins and evolution of the genus Myosotis L. (Boraginaceae)"](https://www.sciencedirect.com/science/article/pii/S1055790302002105). *Molecular Phylogenetics and Evolution*. **24** (2): 180–193. [doi](/source/Doi_(identifier)):[10.1016/S1055-7903(02)00210-5](https://doi.org/10.1016%2FS1055-7903%2802%2900210-5). [ISSN](/source/ISSN_(identifier)) [1055-7903](https://search.worldcat.org/issn/1055-7903). [PMID](/source/PMID_(identifier)) [12144755](https://pubmed.ncbi.nlm.nih.gov/12144755).

1. **[^](#cite_ref-7)** Meudt, HM (1 October 2016). ["Pollen morphology and its taxonomic utility in the Southern Hemisphere bracteate-prostrate forget-me-nots (Myosotis, Boraginaceae)"](https://doi.org/10.1080/0028825X.2016.1229343). *New Zealand Journal of Botany*. **54** (4): 475–497. [doi](/source/Doi_(identifier)):[10.1080/0028825X.2016.1229343](https://doi.org/10.1080%2F0028825X.2016.1229343). [ISSN](/source/ISSN_(identifier)) [0028-825X](https://search.worldcat.org/issn/0028-825X). [S2CID](/source/S2CID_(identifier)) [89118799](https://api.semanticscholar.org/CorpusID:89118799).

1. **[^](#cite_ref-8)** ["Myosotis retrorsa"](https://collections.tepapa.govt.nz/topic/10498). *collections.tepapa.govt.nz*. Retrieved 10 May 2022.

1. **[^](#cite_ref-9)** ["Myosotis retrorsa"](https://www.google.com/search?q=myosotis+retrorsa). *www.google.com*. Retrieved 10 May 2022.

## External links

- [*Myosotis retrorsa* occurrence data from Australasian Virtual Herbarium](https://avh.ala.org.au/occurrences/search?taxa=myosotis+retrorsa#tab_mapView)

Taxon identifiers Myosotis retrorsa Wikidata: Q75862685 Wikispecies: Myosotis retrorsa CoL: 4563Z GBIF: 9999338 iNaturalist: 699917 IPNI: 77177845-1 NZOR: 5dd962c7-c9ad-4d5f-b60f-ae4bfe914c13 Open Tree of Life: 7625393 POWO: urn:lsid:ipni.org:names:77177845-1

---
Adapted from the Wikipedia article [Myosotis retrorsa](https://en.wikipedia.org/wiki/Myosotis_retrorsa) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Myosotis_retrorsa?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.