There’s gold in them thar hills! Morphology and molecules delimit species in Xerochrysum (Asteraceae; Gnaphalieae) and reveal many new taxa
Author
Collins, Timothy L.
Author
Schmidt-Lebuhn, Alexander N.
Author
Andrew, Rose L.
Author
Telford, Ian R. H.
Author
Bruhl, Jeremy J.
text
Australian Systematic Botany
2022
2022-06-09
35
2
120
185
http://dx.doi.org/10.1071/sb21014
journal article
10.1071/SB21014
1446-5701
10903939
Key to species of
Xerochrysum
1. Herbs, rhizomatous; claw of medial phyllaries with a central vein that passes into the lamina; cypselae with persistent pappus and no pappus–pericarp abscission line............................................2
Herbs, or shrub-like, taprooted or sometimes rhizomatous; claw of medial phyllaries with several vascular bundles that terminate at its apex; cypselae with deciduous pappus, or if persisting, then with a distinct pappus–pericarp abscission line.........................7
2. Phyllaries white, pale pink or crimson..........................................3 Phyllaries yellow............................................................................4
3. Stem indumentum densely white-cottony, without glands, becoming glabrescent with age; leaves woolly on margin, otherwise glabrous or cobwebby...............................................
X. milliganii
Stem
indumentum hirsute with stipitate glands; leaves cobwebby to woolly on margin, adaxially hirsute, otherwise glands both sides......................................................................
X. collierianum
4. Stem indumentum densely cottony towards apex, glands absent......5 Stem indumentum cobwebby and glandular with glands towards apex.............................................................................
X. alpinum
5. Outer phyllaries smooth abaxially..................................
X. palustre
Outer
phyllaries scabridulous abaxially.........................................6
6. Cauline leaves
20–60 mm
long and
2–10 mm
wide, glabrous or with sessile glands adaxially....................................
X. andrewiae
Cauline
leaves
25–90 mm
long and
5–20 mm
wide, hispid or scabrid with stipitate glands adaxially.....................
X. subundulatum
7. Cauline leaves abaxially hirsute to tomentose or with scattered septate trichomes........................................................................8 Cauline leaves abaxially without septate trichomes....................18
8. Most cauline leaves less than
10 mm
wide....................................9 Most cauline leaves
10 mm
wide or greater................................14
9. Cauline leaves abaxially with occasional or scattered septate trichomes......................................................................................10 Cauline leaves abaxially hirsute to hispid or tomentose.............12
10. Cauline leaves with persistent stipitate glands on cauline leaf adaxial surface; prostrate habit; far northern
Queensland
coastal headlands......................................................................
X. banksii
Cauline
leaves with fragile stipitate or sessile glands on cauline leaf adaxial surface; erect habit; not in far northern
Queensland
....11
11. Cauline leaves with sessile glands breaking and leaving a varnished appearance;
Victoria
, inland
New South Wales
, and southern
Queensland
.................................................................
X. viscosum
Cauline
leaves with stipitate glands, fragile and usually lost but retaining persistent stipes and not appearing varnished; Top End,
Northern Territory
, and Kimberley,
Western Australia
......
X. boreale
12. Basal rosette usually absent at flowering, flowering stems branched, capitula in open panicles.........................................13 Basal rosette usually present at flowering, flowering stems unbranched, capitula solitary...............................
X. neoanglicum
13. Annual or biennial; taproot present; basal leaf rosette present or usually marcescent; abaxial leaf lamina densely hispidulous with flagelliform trichomes and minute persistent septate bases up to ~
0.02 mm
long; widespread on roadsides and grassy woodlands on basaltic and granitic clay soils.................
X. macsweeneyorum
Perennial
; short rhizome or taproot present; basal leaf rosette absent; leaves hirsute abaxially with flagelliform trichomes on septate bases up to
0.1 mm
long; restricted to gorge rim habitats on skeletal metasedimentary and granitic soils.......
X. copelandii
14. Cauline leaf margin hispid with septate trichomes; habitat not on margins of rainforest or
Nothofagus moorei
forest...................15 Cauline leaf margin woolly with septate trichomes; habitat mostly on margins of rainforest or
Nothofagus moorei
forest......
X. frutescens
15. Populations restricted to northern
New South Wales
..................16 Populations restricted to northern
Queensland
...........................17
16. Cauline leaf abaxial lamina glabrous or with scattered septate flagelliform trichomes; ovate stylar appendages; restricted to Barrington Tops National Park, New South Wales......
X. murapan
Cauline
leaf abaxial lamina pilose with septate flagelliform trichomes; lanceolate stylar appendages; restricted to high-altitude escarpment in New
England
National Park, New South Wales......
X. berarngutta
17. Stylar appendage lanceolate with acute apex; cauline leaf adaxial indumentum hirsute, with slender, lanceoloid septate trichomes, numerous stipitate glands; erect habit........................
X. strictum
Stylar
appendage ovate with obtuse apex; cauline leaf adaxial indumentum hispid, with stout septate trichomes arising from thickened basal cells, stipitate glands few or absent; decumbent habit..............................................................................
X. gudang
18. Most mid-cauline leaves less than
10 mm
wide...........................19 Most mid-cauline leaves greater than
10 mm
wide.....................22
19. Phyllaries broad and rounded......................................................20 Phyllaries narrow and lanceolate.................................................21
20. Erect open habit; annual, or biennial in wetter years; stylar appendage ovate; inland northern
New South Wales
and south-western
Queensland
........................................................
X
. sp. Chinchilla Compact habit; perennial; stylar appendage narrow triangular; coastal headlands in
New South Wales
, and southern and central
Queensland
.......................................................................................
X
. sp.
North Stradbroke Island
(
L. Durrington
675) Qld Herbarium
21. Annual, or biennial in wetter years; foliaceous bract subtending capitulum less than
10 mm
long; south-western
Western Australia
...............................................................
X. macranthum
Perennial
; foliaceous bract subtending capitulum greater than
10 mm
long;
Tasmania
and
Victoria
.......................
X. papillosum
22. Tap rooted; not in alpine habitats...............................................23 Rhizomatous; alpine habitats ....................
X
. sp. Blackfellows Gap
23. Stylar appendage narrow triangular............................................24 Stylar appendage broad triangular or ovate................................25
24. Foliaceous bract subtending capitulum greater than
10 mm
long; cauline leaves hispid adaxially and with large trichomes scattered on leaf lamina and margin; Flinders Ranges and inland areas of southern
South Australia
,
Victoria
and
New South Wales
..........................................................................
X. hispidum
Foliaceous
bract subtending capitulum less than
10 mm
long; cauline leaves sparsely hirsute adaxially; arid
Northern Territory
, northern
South Australia
, and arid
Western Australia
................. ....................................................................................
X. interiore
25. Stems cottony or woolly below capitulum...................................26 Stems hispid or with flagelliform trichomes below capitulum............ .............................................................................................
X. bicolor
26. Phyllaries yellow;
Queensland, New South Wales
or
Victoria
......27 Phyllaries white or pink;
Western Australia
....................
X. wilsonii
27. Cauline leaf adaxial indumentum hispid or hirsute with septate trichomes without flagelliform apices, and older leaves not glabrescent;
Queensland
..................................................................28 Cauline leaf adaxial indumentum hispid with minute flagelliform trichomes, older leaves glabrescent; south-eastern
New South Wales
and eastern
Victoria
.....................................
X. bracteatum
28. Cauline leaves
15–60 mm
wide and
90–150 mm
long, cauline leaf adaxial indumentum sparsely hispid with septate trichomes ........
X
. sp. North Stradbroke Island (L. Durrington 675) Qld Herbarium Cauline leaves
5–30 mm
wide and
15–130 mm
long, cauline leaf adaxial indumentum hirsute with septate trichomes .................. ........................................................................
X.
sp. Tin Can Bay