{{Short description|Species of flowering plant}} {{Use New Zealand English|date=July 2023}} {{Use dmy dates|date=July 2023}} {{Speciesbox | image = SP108821 Myosotis macrantha (Hook.f.) Benth. & Hook.f. WELT Te Papa 1863566 592325.jpg | image_caption = flowering plants of Myosotis macrantha | status = NT | status_system = NZTCS | status_ref = <ref name="NZTCS"/> | genus = Myosotis | species = macrantha | authority = ([[Joseph Dalton Hooker|Hook.f.]])[[Thomas Cheeseman|Cheeseman]]<ref name = ":H" /><ref name = ":C" /> }}

'''''Myosotis macrantha''''' or the '''Bronze Forget-Me-Not'''<ref name="Collections Online h071">{{cite web |title=Bronze forget-me-not, Myosotis macrantha (Hook.f.) Benth. & Hook.f. |website=Museum of New Zealand |url=https://collections.tepapa.govt.nz/object/1955252 |access-date=6 May 2024}}</ref> is a species of [[flowering plant]] in the [[Family (taxonomy)|family]] [[Boraginaceae]], [[Endemism|endemic]] to the [[South Island]] of [[New Zealand]]. [[Joseph Dalton Hooker]] described the species as ''Exarrhena macrantha'' in 1864, and [[Thomas Cheeseman]] transferred it to the genus ''[[Myosotis]]'' in 1885. Plants of this species of [[Forget-me-nots|forget-me-not]] are [[Perennial plant|perennial]] rosettes with ebracteate inflorescences and yellow to dark purple corollas with stamens that are exserted.

== Taxonomy and etymology == ''Myosotis macrantha'' (Hook.f.) Cheeseman is in the plant family [[Boraginaceae]].<ref name=":3">{{Cite web |title=Myosotis macrantha |url=https://www.nzpcn.org.nz/flora/species/myosotis-macrantha/ |access-date=2023-07-29 |website=New Zealand Plant Conservation Network |language=en}}</ref> The species was originally described as ''Exarrhena macrantha'' Hook.f. in 1867 by [[Joseph Dalton Hooker]] in ''[[Handbook of the New Zealand Flora]]''.<ref name=":2">{{Cite web |last=Moore |first=L.B. |title=Boraginaceae. In 'Flora of New Zealand'. (Ed. HH Allan) Vol. 1, pp. 806–833 |url=https://floraseries.landcareresearch.co.nz/pages/Taxon.aspx?id=_2dd90ab4-331f-4d49-bb31-b0a843e65931&fileName=Flora%201.xml |access-date=2022-04-27 |website=(Government Printer: Wellington, New Zealand) floraseries.landcareresearch.co.nz}}</ref><ref name = ":H">{{Cite book |last=Hooker |first=Joseph Dalton |url=https://www.wikidata.org/wiki/Q63468298 |title=Handbook of the New Zealand flora : a systematic description of the native plants of New Zealand and the Chatham, Kermadec's, Lord Auckland's, and Macquarrie's islands |date=1867-01-01 |language=English}}</ref> [[Thomas Cheeseman]] transferred it to ''Myosotis saxosa'' (Hook.f.) Cheeseman in 1885.<ref name=":C">{{Cite journal |last=Cheeseman |first=Thomas |date=1885-01-01 |title=New Species of Plants |url=https://www.wikidata.org/wiki/Q115527957 |journal=Transactions and Proceedings of the New Zealand Institute |language=English |volume=17 |pages=235–236}}</ref> ''Myosotis macrantha'' is not mentioned in ''Genera Plantarum'' by Bentham and Hooker,<ref>{{Cite book |last1=Bentham |first1=George |title=Genera Plantarum |last2=Hooker |first2=Joseph Dalton |publisher=L. Reeve & Co. |year=1876 |volume=2 |location=London}}</ref> and therefore ‘''M. macrantha'' (Hook.f.) Benth. & Hook.f,’ is not the correct author citation.<ref>{{Cite journal |last=Meudt |first=Heidi |date=2021-01-01 |title=Taxonomic revision of five species groups of ebracteate-erect Myosotis (Boraginaceae) endemic to New Zealand, based on morphology, and description of new subspecies |url=https://www.wikidata.org/wiki/Q107671092 |journal=Australian Systematic Botany |language=English |volume=34 |issue=3 |pages=252–304 |doi=10.1071/SB20028|url-access=subscription }}</ref>

The most recent treatment of this species was done by [[Lucy Moore (botanist)|Lucy B. Moore]] in the ''Flora of New Zealand.<ref name=":2" />''

The original specimens ([[syntype]]s) of ''Myosotis macrantha'' were collected by several different collectors at multiple sites in the South Island, New Zealand, and are likely lodged at [[Kew Herbarium]] (e.g. K000787875).<ref>{{Cite web |title=Syntype of Myosotis macrantha on JSTOR |url=https://plants.jstor.org/stable/10.5555/al.ap.specimen.k000787875 |access-date=2023-07-28 |website=plants.jstor.org |doi=}}</ref><ref name=":2" />

Three varieties have been described within ''M. macrantha:''<ref name=":2" />

* ''M. macrantha'' var. ''pulchra'' Cheeseman<ref>{{Cite book |last=Cheeseman |first=Thomas |url=https://www.wikidata.org/wiki/Q51396409 |title=Manual of the New Zealand flora |date=1906-01-01 |language=English}}</ref> * ''M. macrantha'' var. ''westlandica'' [[Donald Petrie (botanist)|Petrie]]<ref>{{Cite journal |last=Petrie |first=Donald |date=1918-01-01 |title=Descriptions of new native flowering-plants |url=https://www.wikidata.org/wiki/Q114397649 |journal=Transactions and Proceedings of the New Zealand Institute |volume=50 |pages=207–211}}</ref> * ''M. macrantha'' var. ''diversa'' [[George Simpson (botanist)|G.Simpson]] & [[John Scott Thomson|J.S.Thomson]]<ref>{{Cite journal |last1=Simpson |first1=George |last2=Thomson |first2=John Scott |date=1943-01-01 |title=Notes on Some New Zealand Plants and Descriptions of New Species. |url=https://www.wikidata.org/wiki/Q89182734 |journal=Transactions and Proceedings of the Royal Society of New Zealand |language=English |volume=73 |pages=155–171}}</ref> * ''M. macrantha'' var. ''macrantha'' ([[Autonym (botany)|autonym]])

Since their descriptions, these varieties have not been used or referred to often in the literature, and Lucy Moore suggested that none of these varieties "is sufficiently distinct to be maintained without further evidence".<ref name=":2" />

Vegetatively, ''Myosotis macrantha'' is similar to ''M. explanata,'' whereas the flowers are similar to those of ''M. arnoldii.''<ref name=":2" /><ref name=":3" />

== Phylogeny == ''Myosotis macrantha'' was shown to be a part of the [[monophyletic]] southern hemisphere lineage of ''Myosotis'' in [[Phylogenetics|phylogenetic]] analyses of standard DNA sequencing markers ([[Ribosomal DNA|nuclear ribosomal DNA]] and [[chloroplast DNA]] regions) of New Zealand ''Myosotis''.<ref name=":1">{{Cite journal |last1=Meudt |first1=Heidi |last2=Prebble |first2=Jessica |last3=Lehnebach |first3=Carlos A. |date=2014-11-07 |title=Native New Zealand forget-me-nots (Myosotis, Boraginaceae) comprise a Pleistocene species radiation with very low genetic divergence |url=https://www.wikidata.org/wiki/Q54789770 |journal=Plant Systematics and Evolution |language=English |volume=301 |issue=5 |pages=1455–1471 |doi=10.1007/S00606-014-1166-X|url-access=subscription }}</ref><ref name=":0" /> Within the southern hemisphere lineage, species relationships were not well resolved.<ref name=":0">{{Cite Q|Q30707919}}</ref><ref name=":1" /> Of the five individuals of ''M. macrantha'' included in the study, up to three individuals clustered together and sometimes with individuals of ''M. angustata'' or ''M. explanata,'' depending on the analysis''.<ref name=":1" />''

== Description == '''''Myosotis macrantha''''' plants are rosettes. The rosette leaves have broad [[Petiole (botany)|petioles]] that are about as long as the leaf blades. The rosette leaves are 30–120&nbsp;mm long by 6–20&nbsp;mm wide (length: width ratio c. 5–6: 1), and the leaf blade is obovate to lanceolate-spathulate, widest below, at or above the middle, with a [[Acute (botany)|subacute]] apex. Both surfaces of the leaf are uniformly and sparsely to densely covered in patent to erect hairs. The upper surface of the leaf has densely distributed appressed to erect antrorse (forward-facing) whereas on the lower surface the hairs are mostly appressed and retrorse (backward-facing) except for some antrorse hairs near the tip'''.''' Each rosette has several ascending to erect, ebracteate [[inflorescence]]s that are up to 300&nbsp;mm long. The cauline leaves are similar to the rosette leaves, but are smaller and become smaller toward the top of the inflorescence, lanceolate, and subacute, and have hairs similar to the rosette leaves except the upper cauline leaves may not have retrorse hairs on the lower surfaces. The flowers are many per inflorescence, and each is borne on a short [[Pedicel (botany)|pedicel]], without a bract. The calyx is 6–9&nbsp;mm long at flowering and fruiting, lobed to one-half tor more of its length, and densely covered in patent to erect, antrorse hairs that are mostly antrorse, but some are retrorse near the base and others are hooked. The corolla is yellow, brownish or purple and can reach 15 &nbsp;mm in diameter, with a cylindrical tube, and small scales alternating with the petals (the scales are sometimes absent or obscure). The anthers are exserted, surpassing the faucal scales. The nutlets are c. 3&nbsp;mm long by 1.5&nbsp;mm wide.<ref name=":2" />

The [[pollen]] of ''Myosotis macrantha'' is unknown.

The [[chromosome number]] of ''M. macrantha'' is unknown.

Flowering December–March and fruiting February–May.<ref name=":3" />

== Distribution and habitat == ''Myosotis'' ''macrantha'' is a [[forget-me-not]] that occurs in high-elevation habitats in the South Island of New Zealand, particularly along the western side, in Western Nelson, Canterbury, Westland, Otago and Fiordland.<ref name=":2" /><ref name=":3" /><ref>{{Cite web |title=Myosotis macrantha - GBIF |url=https://www.gbif.org/species/8166715 |access-date=2023-07-29 |website=www.gbif.org |language=en}}</ref>

''Myosotis macrantha''is likely to be an outcrossing species, with plants requiring a pollinating vector to achieve pollination and seed set.<ref name=":12">{{Cite web |title=Breeding systems and rarity in New Zealand Myosotis |url=https://www.wikidata.org/wiki/Q112856523 |access-date=2023-07-27 |website=www.wikidata.org |language=en}}</ref>

== Conservation status == ''Myosotis macrantha'' is listed as Not Threatened on the most recent assessment (2017–2018) under the [[New Zealand Threat Classification System|New Zealand Threatened Classification]] system for plants.<ref name="NZTCS">{{Cite journal |last1=Lange |first1=Peter J. de |last2=Rolfe |first2=Jeremy R. |last3=Barkla |first3=John W. |last4=Courtney |first4=Shannel P. |last5=Champion |first5=Paul D. |last6=Perrie |first6=Leon R. |last7=Beadel |first7=Sarah M. |last8=Ford |first8=Kerry A. |last9=Breitwieser |first9=Ilse |last10=Schönberger |first10=Ines |last11=Hindmarsh-Walls |first11=Rowan |date=May 2018 |title=Conservation status of New Zealand indigenous vascular plants, 2017 |url=https://www.doc.govt.nz/globalassets/documents/science-and-technical/nztcs22entire.pdf |journal=New Zealand Threat Classification Series |volume=22 |pages=45 |oclc=1041649797}}</ref>

== Gallery == <gallery mode="packed" heights="170"> File:SP111325 Myosotis macrantha (Hook.f.) Benth. & Hook.f. WELT Te Papa 1955252 643857.jpg|Close-up of light coloured flowers File:SP105611 Myosotis macrantha (Hook.f.) Benth. & Hook.f. WELT Te Papa 1592395 400164.jpg|Plant with dark maroon flowers File:SP106615^B Myosotis macrantha (Hook.f.) Benth. & Hook.f. WELT Te Papa 1697940 465881.jpg|alt=|Close-up of flowers with yellow corolla lobes File:SP108821 Myosotis macrantha (Hook.f.) Benth. & Hook.f. WELT Te Papa 1863566 589659.jpg|Rosette leaves </gallery>

== References == {{Reflist}}

== External links == {{Commons}}

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

{{Taxonbar|from=Q17416965}}

[[Category:Myosotis|macrantha]] [[Category:Flora of the South Island]] [[Category:Plants described in 1867]] [[Category:Taxa named by Joseph Dalton Hooker]]