Flora of New Zealand Series

Fls us. in cymes, ebracteate, bracteate only at base, or with lflike bract associated with each fl., occ. solitary and terminal; calyx persistent; corolla-tube infolded to form "scales" or "glands" at throat, lobes contorted in bud; stamens with anthers either at least partly below scales, or wholly above scales; ovary 4-celled, style slender; nutlets 4, smooth and shining, mostly dark brown or black when mature. Annual or perennial hairy herbs. More than 50 spp. mostly of temperate lands. Of 34 spp. in N.Z. all are endemic except possibly some forms here included under the Australian M. australis, and perhaps M. antarctica.

SYNOPSIS

• A.
• • Anthers at least partly below corolla-scales (MYOSOTIS)
  • 1.
  • • Lvs associated with fls; flowering branches very short, or ± prostrate, or very lax
    • (a)
    • • Fls solitary and terminal:
      • 1. uniflora, 2. pulvinaris, 3. glabrescens
    • (b)
    • • Fls several, apparently lateral
      • (i)
      • • Corolla-lobes broad, rounded:
        • 4. elderi, 5. colensoi, 6. cheesemanii
      • (ii)
      • • Corolla-lobes narrow, oblong to obovate:
        • 7. tenericaulis, 8. pygmaea, 9. antarctica
  • 2.
  • • No lvs amongst fls; flowering branches ± erect
    • (a)
    • • Either retrorse or hooked hairs present on some lvs:
      • 10. traversii, 11. australis, 12. suavis, 13. explanata
    • (b)
    • • Neither retrorse nor hooked hairs on lvs:
      • 14. capitata, 15. albo-sericea, 16. goyenii, 17. forsteri
• B.
• • Anthers wholly above corolla-scales (EXARRHENA)
  • 1.
  • • Few or no lvs amongst fls
    • (a)
    • • Fls us. many, without associated lvs
      • (i)
      • • Internodes between frs long:
        • 18. venosa, 19. laeta, 20. laingii, 21. petiolata
      • (ii)
      • • Internodes between frs short
        • α
        • • Filaments much > anthers:
          • 22. eximia, 23. monroi, 24. saxosa, 25. amabilis, 26. concinna
        • β
        • • Filaments not much > large anthers:
          • 27. rakiura, 28. macrantha, 29. oreophila, 30. arnoldii, 31. angustata
    • (b)
    • • Fls us. few, lower us. with lvs:
      • 32. lyallii
  • 2.
  • • Each fl. associated with a lf:
    • 33. spathulata, 34. matthewsii

R. Brown's genus Exarrhena (Prodr. 1810, 459), based on the Australian E. suaveolens and differing from Myosotis chiefly in the exserted stamens, was treated as a section of Myosotis by Bentham and Hooker (Gen. Pl. 2, 1876, 858). Though the position of the anthers in relation to corolla-scales is used in the first division of the key below, there is no firm conviction that this leads to the most nearly natural arrangement. One sp. is difficult to place in either section. Relative lengths of anther and filament remain fairly constant within any one sp. but between spp. with exserted stamens there is a wide range of ratios. Corolla-shapes do not offer any clear-cut distinction between the two sections. As Cheeseman pointed out (Man. N.Z. Fl. 1925, 746) "several species greatly resemble one another in habit and foliage, although widely different in the flowers". As comparable pairs from the two sections may be mentioned: tenericaulis / spathulata (some forms); forsteri / venosa; explanata / macrantha.

Bracteate cymes, yellow corollas and exserted stamens are little known in the genus outside N.Z.

N.Z. spp. are predominantly perennial, mostly with long-lived stem bearing adventitious roots amongst the old lf-bases. Lvs of vegetative stems are us. petiolate and form a ± compact rosette giving off axillary lateral flowering branches (occ. again branched) that bear progressively more sessile stem-lvs. Vegetative laterals sts layer themselves and plants can be multiplied in cultivation in this way; flowering laterals root much more rarely. Many spp. are recorded as sweetly scented.

Several introduced spp. are thoroughly naturalized and of these the ± aquatic M. caespitosa has been collected in some remote localities, including several in Fiordland. An exotic plant may have been the basis of M. subvernicosa Col. in T.N.Z.I. 24, 1891, 390 from "Sides of streamlets, low grassy plains, south of Dannevirke, County of Waipawa: 1891, W.C." The only known specimen is one at Kew presented by Colenso in 1897; according to a statement on the label it was not part of his original material.

Fig. 30. MYOSOTIS. Corollas and stamens. © All rights reserved. [Image: 4X1E]

Fig. 31. MYOSOTIS. Calyces © All rights reserved. [Image: 4X1F]

Fig. 32. MYOSOTIS. Leaf-indumentum: adaxial surface on left, abaxial on right; longitudinal section below. © All rights reserved. [Image: 4X1G]