48 
single pair of secondary veins arising from 
above the base of the blade. Inflorescence 
axillary, cymose; peduncle slender, with 2 
persistent and opposite bracteoles, bearing a 
single flower; pedicel absent. Sepals 5, free, 
quincuncial, enlarging and becoming scarious 
at fruiting with 3-5 prominent longitudinal 
veins. Corolla campanulate to slightly funnel- 
shaped, shallowly 5-lobed, with sparsely 
hairy midpetaline bands. Stamens 5; filaments 
flattened and dilated downwards, fused 
to the corolla tube at the base, glabrous or 
tuberculate; anthers ovate-oblong, sagittate, 
apex rounded and emarginate, dehiscing 
longitudinally with no twisting. Ovary 1- 
celled, glabrous; ovules 2, basal; disc annular; 
style 1, filiform and bearing a bi-globose 
stigma. Utricle chartaceous, with a persistent 
style base, indehiscent; seed 1, glabrous, with 
a basal circular hilum. 
Etymology : Named in honour of Louis-Isidore 
Duperrey, a marine officer, hydrologist and 
plant collector who accompanied Gaudichaud 
on the “Uranie” during the Freycinet 
expedition of 1817-1820. 
Distribution : The genus is endemic to 
Australia and the three species occur in 
subtropical to warm temperate, arid to semi- 
arid areas. 
Austrobaileya 8(1): 47-54 (2009) 
Relationships and Diagnostic Characters : 
Hallier (1893) described the tribe Poraneae 
which included Porana and a number of other 
non-Australian genera. However, studies by 
Staples (1990) and Stefanovic et al. (2002) 
indicated that Poraneae was not monophyletic 
and embraced a number of unrelated genera. 
This has led to a reallocation of the genera 
assigned to the Poraneae (Stefanovic et al 
2003). Porana was transferred to the tribe 
Dichondreae (Choisy) Choisy, while some 
other genera including Duperreya were 
incorporated in a new tribe Cardiochlamyeae 
Stefanovic & Austin. The closest relatives 
of Duperreya are the genera Cordisepalum 
Verde., Dinetus Sweet, Poranopsis Roberty 
and Tridynamia Gagnep., all of which occur 
in southeast Asia. Duperreya is distinguished 
from these genera in having narrower leaves 
and solitary flowers. Staples (2006) also found 
the pattern of leaf venation in Duperreya 
(a single pair of secondary veins departing 
from the midvein near the base of the blade) 
distinguished it from its near relatives (with 
two pairs of secondary veins arising from the 
base). 
Key to the species of Duperreya 
1 Outer sepals narrowly ovate to narrowly elliptic, with L:B ratio >3, 3.5-6 
mm wide at fruiting.1. D. commixta 
1. Outer sepals ovate to elliptic with a L:B ratio <2.5, >8 mm wide at 
fruiting.2 
2 Outer sepals 3-5.5 mm wide at flowering with a L:B ratio <2 and 10-19 
mm wide at fruiting with a L:B ratio of <1.5.2. D. sericea 
2. Outer sepals 2.5-3 mm wide at flowering with a L:B ratio >2 and 8-11 
mm wide at fruiting with a L:B ratio of >1.5.3. D. halfordii 
1. Duperreya commixta (Staples) Staples, 
Blumea 51: 451 (2006); Porana commixta 
Staples, Nuytsia 6: 52 (1987). Type: Western 
Australia. 52 km W of Wiluna, 29 August 
1970, P.G. Wilson 8965 (holo: PERTH n.v., iso: 
A n.v., CANB n.v., K n.v.). 
Illustration : Staples (1987: 53 fig 1; 55 fig 2), 
as Porana commixta. 
Perennial; stems climbing, woody at the base, 
moderately to densely sericeous, becoming ± 
glabrous with age; bifid hair arms 0.1-0.3 mm 
long. Leaf petiole 0.3-1 (-2) mm long, 0.02- 
0.06 times as long as the blade; blade linear 
to linear-ovate, 15-50 mm long, 1-5 mm 
wide with a length:breadth ratio of 7.5-20, 
apex acute, base rounded to obtuse, sparsely 
to moderately densely sericeous above, 
