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
Xerochrysum hispidum
T.L.Collins & I.Telford
,
sp. nov.
Type
:
AUSTRALIA
:
New South Wales
:
South Western Plains
:
Mid
Western Highway
,
21 km
from
Rankins Springs
towards
West Wyalong
,
12 Oct. 2019
,
I.R. Telford
13546,
J.J. Bruhl
&
S. Dema
, (holo:
NSW
!; iso:
BRI
!,
CANB
!,
MEL
!,
NE 109359
!,
US
!).
[
Xerochrysum bracteatum auct
. non
(Vent.) Tzvelev: N.N. Tzvelev,
Novosti Sist. Vyssh. Rast.
27: 151 (1990),
p.p.
populations in south-western
New South Wales
, inland
South Australia
and inland
Victoria
with prominent, robust, hispid septate trichomes scattered on the leaf lamina adaxial surface, leaf margin and abaxial midvein only].
Diagnosis
Distinguished from
X. bracteatum
and
X. bicolor
by the presence of foliaceous bracts subtending capitula
15–35 mm
long (
8–10 mm
long in
X. bracteatum
;
5–6 mm
long in
X. bicolor
), and the prominent, robust, hispid septate trichomes scattered on the leaf lamina adaxial surface, leaf margin and abaxial midvein. Further distinguished from
X. bicolor
by a strictly annual life form (
v.
perennial
), and the attenuate leaf base (
v.
auriculate
).
Erect, taprooted, annual herb,
10–80 cm
tall, depending on rainfall.
Stems
and
branches
cobwebby and hispid with septate trichomes, and with glands; internode length
15–30 mm
.
Basal leaf rosette
may be present or absent at flowering.
Basal leaves
obovate to spathulate,
50–150 mm
long and
10–40 mm
wide, base amplexicaul, margin hispid and pilose with septate trichomes, apex mucronate and apiculate; abaxial indumentum with glands, midvein indumentum pilose with septate trichomes; adaxial leaf surface glabrous (with scattered septate trichomes).
Cauline leaves
Fig. 27. Distribution of
Xerochrysum gudang
.
Fig. 28. Isotype of
Xerochrysum gudang
(T.L.Collins 1061 & J.J.Bruhl
, NE 107429).
oblanceolate to obovate,
60–160 mm
long and
10–30 mm
wide, base amplexicaul and attenuate, margin cobwebby and hispid with septate trichomes, apex acute and mucronate;
abaxial indumentum
with glands, midvein indumentum hispid or pilose with septate trichomes;
adaxial indumentum
hispid with septate trichomes, and with additional scattered large septate trichomes, and with glands.
Foliaceous bracts subtending capitula
15–35 mm
long, margin hispid.
Capitula
35–50 mm
wide, terminal, in panicles.
Outer phyllaries
broad-ovate, brown or straw-coloured, basal margin fimbriate and hispid, abaxial surface smooth, apex apiculate.
Medial phyllaries
oblong to ovate, abaxially yellow, apex acuminate to cuspidate, or apiculate.
Stylar appendages
narrowly triangular to deltoid.
Cypsela
oblong, ~
3.3 mm
long and
1 mm
wide, cross-section squarish; pericarp brown, idioblasts present.
Pappus
deciduous, ~
8.5 mm
long.
Distribution
Occurs sporadically following winter rainfall over a broad area of
South Australia, Victoria and New South Wales
, in the Eyre Yorke Block, Gawler, Flinders Lofty Block, Murray–Darling Depression, and Riverina bioregions (
Fig. 29
).
Phenology
Recorded flowering August–October (
Fig. 30
).
Habitat
Shrubby and grassy eucalypt woodlands and
Acacia
shrublands, on orange–red sandy loams and red, gravelly, clay soils.
140°0
̍
0
̎
E
140°0
̍
0
̎
E
Conservation status
Occurs over a wide geographical area, including in several conservation reserves and is not considered to be rare or threatened. We recommend a status of ‘
Least Concern
’ (
IUCN 2019
).
Notes
The informal phrase name
Xerochrysum
sp.
Flinders Range
NE
Herbarium has been used at
NE
for curatorial purposes and this study.
Etymology
The specific epithet is from the Latin,
hispidus
(rough, shaggy, hairy), in reference to the indumentum, comprising scattered, large, spreading septate trichomes, occurring abaxially along the leaf midrib and adaxially over the lamina, which are particularly helpful in identifying specimens.
Selected specimens examined
SOUTH AUSTRALIA
: unincorporated:
Balcanoona
, near
Nudlamutana Well
,
26 Oct. 1967
,
H. Eichler
19646
(
AD
!)
.
Elliston
:
Hambidge Flora
and
Fauna Reserve
,
18 Sep. 1966
,
C.R. Alcock
1023
(
AD
!)
.
Cleve
:
Hincks National Park
, summit of
Verran Hill
,
6 Oct. 1968
,
J.R. Wheeler
733
(
AD
!)
.
NEW SOUTH WALES
: unincorporated:
Scotia Sanctuary
,
22 May 2011
,
D. Wood
240
(
CANB
!)
.
Lachlan
:
2.5 miles
[~
4 km
] E from
Euabalong
turn-off from
Lake Cargelligo
,
23 May 1969
,
P.N. Martensz
178
(
CANB
*)
.
Cobar
:
10.5 miles
[~
16.8 km
]
S of Cobar on Nymagee
road,
30 Sep. 1966
,
C.W.E. Moore
4487
(
CANB
*)
.
Coolamon
:
Near Ariah Park
, ~
40 km
WNW of Temora
,
28 Oct. 1978
,
C.J. Shepherd
870
(
CANB
*)
.
VICTORIA
:
Mildura
:
Murray-Sunset National Park
,
10 Oct. 2014
,
V. Stajsic
7611
(
MEL
!)
;
Hattah Lakes National Park
,
1 Oct. 1948
,
A.C. Beauglehole
1101
(
MEL
!)
; ~
10.5 miles
[~
16.8 km
] NW of
Warooka
,
25 Oct. 1967
,
T. Smith
774
(
AD
!)
.