A new subspecies of Grevillea brachstylis (Proteaceae) from the Whicher Range

2009·1.7 MB·English

by  Greg Keighery

A NEW SUBSPECIES OF QREVILLEA BRACHSTYLIS
(PROTEACEAE) FROM THE WHICHER RANGE
By GREG KEIGHERY
Department of Environment and Conservation,
Western Australian Wildlife Research Centre
P.O. Box 51, Wanneroo, Western Australia, 6065.
ABSTRACT
Grevillea brachystylis subspecies grandis Keighery is described
and illustrated. This newly described taxon is a very rare
endemic of red-loam soils at the base of the Whicher Range,
south-east of Busselton.
INTRODUCTION Keighery (1990) who divided it
into two species, one with two
Over the past decade the
subspecies. One species (G.
Western Australian Department
bronwenae) is confined to the
of Environment and Conserv¬
Blackwood Plateau and the other
ation (previously the Depart¬
(G. brachystylis) is comprised of
ment of Conservation and Land
two subspecies; Grevillea
Management) has undertaken
brachystylis subspecies brachystylis
intensive floristic and reserve
and subspecies australis on the
surveys of the Swan Coastal Plain
Swan and Scott Coastal Plains
(Gibson et al. 1994; Keighery 1999).
respectively.
Currently these surveys are
continuing under a new Continuing studies of the flora
program entitled “Swan Bioplan” of the Whicher Range and
and have been extended to escarpment noted that variation
include the Darling and Whicher within Grevillea brachstylis subsp.
Escarpments of their respective brachystylis is discontinuous in
ranges (Keighery et al 2008). This this area and that a third
is the fourth paper in a series on subspecies can be recognized.
the flora and vegetation of the This new subspecies is confined
Whicher Range (Keighery et al. to the interface between the
2008; Keighery 2008 a&b). Whicher Escarpment and the
Swan Coastal Plain.
The Grevillea brachystylis species
complex has been studied by
11
TAXONOMY mm, folia 102-109 mm longa vs
40-52 mm.
This rare form of Grevillea
brachystylis differs from the type Typus: SSE of Busselton, 28-Aug.-
form of G. brachystylis in being an 1985, G.J. Keighery s.n. (Holo:
erect shrub to 2 metres tall, PERTH 1071904, Iso: CANB).
although normally less. The
An erect few branched non
plant lacks a lignotuber and has
lignotuberous shrub to 2 metres
only 1-3 stems per plant, which
tall. Branchlets terete, up to 2
are much more robust than the
metres long, sparsely tomentose.
type form. Flowers, pedicels and
Leaves 102-110 mm long by 12
leaves are also much larger, in all
mm wide, spreading to ascend¬
measurements (Table 1).
ing, sessile, simple, linear to
Although occurring in the same obovate, obtuse, mu cron ate,
general location south of upper surface flat to concave,
Busselton, both forms of Grevillea granulate, pubescent but soon
brachystylis are never sympatric glabrous, margins recurved,
being ecologically separated, lower surface pubescent to
without a chance to hybridize. glabrous. Conflorescence de-
The forms differ in habitat, habit flexed, subsessile to pedunculate,
and size of floral and vegetative terminal to axillary, 4-7 flowered,
organs; therefore, sub specific peduncle bracteate, villous, rachis
rank seems most appropriate for
villous, bracts 4-6 mm long,
this rare form. imbricate in bud, ovate,
tomentose, caducous at flowering.
Qrevillea brachstylis subsp. Flowers acroscopic, pedicels 6-8
grandis G.J. Keighery subspecies mm long, tomentose to villous,
nov (Figures 1 and 2) torus 3-4 mm across, very
Differt a Grevillea brachystylis oblique, nectary v shaped, entire.
ramis erecta, flores larger: Perianth 11-12 mm long, 4-5 mm
pedicels 6-8 mm longa vs 2-3 wide, cohering at flowering,
Table 1. Character States of the nominate and new subspecies
Character subspecies grandis subspecies brachystylis
FLORAL
flower limb 11 mm 6 mm
Pedicel 6-8 mm 2-3 mm
pollen presenter 5 mm 2 mm
LEAF
leaf length 102-109 mm 40-52 mm
leaf width 12 mm 5 mm
Lignotuber absent present
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Figure 1. Habit of Grevillea brachystylis subspecies grandis. Type population. Photo
by Bronwen Keighery.
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Figure 2. Flowers and pods of Grevillea brachystylis subsp. grandis. Type population.
Photos by Bronwen Keighery.
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oblong, geniculate from halfway the base of the Whicher Range.
along, dilated ventrally at base, This corresponds to the Jindong
ridged, sparsely tomentose out¬ Subsystem of the Abba soils (Tille
side, pubescent inside, cohering and Lantzke 1990) of the Swan
except along dorsal suture from Coastal Plain, which have almost
curve to limb, limb revolute, entirely been cleared for
ovoid with a point, dilated on agriculture. Only three popu¬
dorsal side, densely brown, lations of this subspecies are
tomentose segments separating at known, all occurring on narrow
flowering. Pistil 11—15 mm long, road verges. The subspecies
stipe 5 mm long, pilose, ovary regenerates from seed following
villous, style stout (ca 1.5 mm fires and is able to cope with
wide), pubescent, exposed at considerable disturbance.
curve of perianth at flowering,
Conservation Code. Listed as Criti¬
but not exserted, afterwards
cally endangered. Known only
straight and scarcely exceeding
from three small roadside popu¬
perianth, style end beaked, pollen
lations south-east of Busselton.
presenter red, 5 mm long, lateral,
Notes. This is an attractive and
oblong elliptic, concave. Fruit 15-
easily grown member of the
17 mm long, 5-7 mm wide, erect,
complex.
ovoid, tomentose. Seed 7-9 mm
long, elliptic with recurved
margins, smooth on both sides, DISCUSSION
with a terminal eliasome, 3-4 mm
This variant of Grevillea
long.
brachystylis with an erect habit
Other collections examined. Base of and large flowers could be
Whicher Scarp, SSE of Busselton,
responsible for the confusion
05-Dec,-1992. G.J. Keighery 13150
that has been expressed in some
(PERTH); Base of Whicher Scarp,
flora treatments (Wheeler et al.
SSE of Busselton, 2-May-1997. A.
2002) in differentiating herb¬
Webb 038; Base of Whicher Scarp,
arium collections between
SSE of Busselton, 27-July-2005. J.
Grevillea brachystylis subsp.
Liddelow 12; Base of Whicher
brachystylis (a Swan Coastal Plain
Scarp, SSE of Busselton, 30-Oct,-
endemic, centred on the Abba
2001. M. Soutar 63 (PERTH).
system) and Grevillea bromvenae (a
Precise locations are not given
Blackwood Plateau endemic,
because of the conservation
centred on the Whicher Scarp,
significance of this subspecies.
predominately around the
Ecology/conservation. This sub¬ headwaters of the Sabina and
species grows only in Marri Abba Rivers with a few ouliers).
(Corymbia calophylla) / Jarrah The other subspecies of Grevillea
(Eucalyptus marginata) or rarely brachystylis, subspecies australis is
Mountain Marri (Corymbia a Scott Coastal Plain endemic, has
haematoxylon) woodland on leathery leaves, a densely hairy
brown lateritic clay loams along perianth and a blue style end (see
15
photos and sketches in Olde and and LYONS, M.N. 1994. A Floristic
Marriott 1995, page 69 and Survey of the Southern Swan Coastal
Keighery 1990). Plain. Report for the Australian
Heritage Commission by the De¬
However, as detailed in Keighery
partment of Conservation and
(1990) and Olde and Marriott
Land Management and the Con¬
(1995) living material of both
servation Council of Western
species can be readily differ¬
Australia (Inc.).
entiated on numerous floral
characters, not just size. Grevillea KEIGHERY, G.J. 1990. Taxonomy
brachystylis has a decumbent of the Grevillea brachystylis species
habit with numerous short complex. Nuytsia 7:125-131.
stems, with spreading narrow
KEIGHERY, G.J. 1999. Conservation
leaves, ovate floral bracts and
status of the vascular flora of the south¬
flowers that are ventrally dilated,
ern Swan Coastal Plain. Report for
geniculate in the upper half with
Environment Australia. Depart¬
the recurved portion dilated on
ment of Conservation and Land
dorsal side, a broad style with a
Management, Perth.
beaked end (see photos and
sketches in Olde and Marriott KEIGHERY, G.J. 2008a. A New Spe¬
1995, page 68 and Keighery 1990). cies of Lomandra (Lomandraceae)
Grevillea bronwenae is an erect from the Whicher Range, Western
few branched shrub with tri¬ Australia. Western Australian
angular floral bracts and flowers Naturalist 26:16-20.
that are undilated, a narrow style KEIGHERY, G.J. 2008b. A New
that is unbeaked and blue (see Subspecies of Loxocarya striata
Olde and Marriott 1995, page 72 (Restionaceae) from the Whicher
and Keighery 1990). The new sub¬ Range. Western Australian Natural¬
species has the erect habit of G. ist 26:139-145.
bronwenae (Figure 1) but the
KEIGHERY, G.J., KEIGHERY, B.J.
flowers shown in Figure 2,
and GIBSON, N. 2008.Floristics of
although much larger, are the
the Whicher Range L Flora and
same shape as normal G.
Vegetation of Dardanup Forest
brachystylis, not G. bronwenae.
Block. Western Australian Natural¬
ist 26: 42-66.
ACKNOWLEDGEMENTS
KEIGHERY, B.J., KEIGHERY, G.J.,
Swan Bioplan, a program WEBB, A., LONGMAN, V., and
GRIFFIN, E.A. 2008. A Floristic
established by the Minister of
Survey of the Whicher Scarp. De¬
Environment provided funding
partment of Environment and
for aspects of this study.
Conservation, Kensington.
OLDE, P. and MARRIOTT, N. 1995.
REFERENCES
The Grevillea Book, Vol. 2.
GIBSON, N., KEIGHERY, B.J., Kangaroo Press, Kenthurst, New
KEIGHERY, G.J., BURBIDGE, A.H. South Wales.
16
THACKWAY, R. and CRESS-
WELL, I.D. 1995. An interim biogeo¬
graphic regionalisation for Australia,
version 4. (Australian Nature
Conservation Agency: Canberra).
TILLE, P. and LANTZKE, N. 1990.
The Busselton-Margaret River land
capability study. Western Aus¬
tralian Department of Agri¬
culture. Land Resources Series No.
5.
WHEELER, )., MARCHANT, N.
and LEWINGTON, M. 2002. Flora
of the South West, Vol 2. University
of Western Australia Press,
Nedlands.
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