88 FABACEAE 
apparently simple, petiolate; blades linear, rarely 
narrowly lanceolate to narrowly oblanceolate, 
(6)10-35(50) mm long, 1-3(4) mm wide, hairs 
moderately dense or dense, appressed, apex acute and 
shortly mucronate. Inflorescence (2)5-15(25) mm 
long, shorter than leaf. Calyx 1.5-4 mm long, lobes 
longer than tube. Standard red, obovate to orbicular. 
Pod ascending, globular, 2-3 mm long, 1.5-1.8 mm 
wide, white or grey strigose with dense, appressed 
hairs; apex shortly beaked; endocarp not spotted. 
Seed 1. Flowering: Feb - Mar; fruiting: Mar - May. 
Fig. 26 
Throughout the Old World tropics from north east 
Africa to tropical Australia extending to SA and 
northern NSW. Common in the DR. Recorded from a 
wide range of well drained habitats, but especially 
disturbed sites. 
I. parviflora Wight & Arn. 
Erect, annual herb to 0.75(1.5) m high. Indumentum 
of appressed, hyaline, white or greenish equally 2- 
armed hairs, sparsely distributed on stems. Stipules 
narrow and triangular or subulate, 1-2 mm long. 
Leaves usually pinnate, rachis furrowed, multicellular 
hairs between leaflet pairs absent; Jeaflets (1,3)5-11, 
linear, narrowly lanceolate, sometimes narrowly 
elliptic or ovate, usually glabrous above, sparsely to 
moderately densely appressed-hairy below, apex 
obtuse and shortly mucronate; lateral leaflets opposite 
(10)20-42 mm long, 1-6 mm wide; terminal leaflet a 
little longer. Inflorescence 10-30 mm long, shorter 
than leaf. Calyx 1.5-3 mm long, lobes equal to or 
longer than the tube. Standard pale red to red, obovate, 
glabrous. Pod descending, terete or compressed- 
terete, 20-40 mm long, 2-3 mm wide, yellowish to 
light brown, indumentum of moderately dense 
appressed hairs; apex upturned and shortly beaked; 
endocarp not spotted. Seeds 10-14. Flowering: Feb - 
May; fruiting: Mar - May. Fig. 26 
Occurs in South Africa, north east Africa and India. 
In tropical Australia it commonly occurs on heavier 
soils in grasslands and Eucalypt savanna, as well as 
on roadsides. Relatively uncommon in the DR. 
A number of specimens from an area just north of 
Pine Creek have leaves that are mainly 1- or 3- 
foliolate. Although the species is quite variable, this 
phenomenon is remarkable since such leaves are 
usually found only occasionally on individuals with 
higher leaflet numbers rather than in whole 
populations. The species has recently been transferred 
to Indigastrum as I. parviflorum (Wight & Arn.) 
Schrire (Schrire, 1992). 
I. polygaloides M.Scott 
Prostrate perennial herb 0.1-0.3 m high, with a 
Indigofera 
thickened taproot. Indumentum of appressed, white, 
2-armed hairs, moderately dense on the angular stems. 
Stipules narrowly triangular to linear, 2-4 mm long. 
Leaves 3-foliolate; rachis furrowed, multicellular hairs 
between leaflet pairs absent; leaflets obovate to 
elliptical, hairs sparse to moderately dense, unequally 
2-armed and spreading above, equally 2-armed and 
appressed below, apex obtuse and apiculate; basal 
leaflets opposite, 5-20 mm long, 3-12 mm wide; 
terminal leaflet slightly larger. Inflorescence 60-160 
mm long, exceeding the leaf. Calyx 2.5-4 mm long, 
~ Jobes longer than the tube. Standard pink to purplish- 
red, obovate. Pod spreading, straight or rarely curved, 
4-angled, 18-24 mm long, c. 1.5 mm wide, brown, 
indumentum of sparse to moderately dense, appressed 
hairs, apex shortly beaked; endocarp not spotted. 
Seeds mostly 7-10. Flowering: Jan - Mar; fruiting: 
Mar - May. Not illustrated. 
Endemic to Australia, from a few scattered localities 
in Qld, NT and WA. Occurs on well drained stony or 
sandy soils in open woodland. The species is similar 
to and has previously been included in /. trita but 
differs in having a swollen perennial taproot, long 
inflorescences with paler flowers, and a more slender 
fruit. 
I. saxicola F.Muell. ex Benth. 
Erect perennial shrub to 2 m high. Indumentum of 
appressed, hyaline or white (rarely brown) equally 2- 
armed hairs, sparse to moderately dense on young 
stems. Stipules triangular, 0.5-1.2 mm long. Leaves 
pinnate, rachis furrowed, multicellular hairs between 
leaflet pairs sparse to moderately dense; leaflets 
5-9(11), ovate to obovate, glabrescent or hairs sparse 
and appressed, apex acute, or obtuse and apiculate; 
lateral leaflets 15-30(40) mm long, 10-22 mm wide; 
terminal leaflet to 45 mm long and 30 mm wide. 
Inflorescence usually 55-210 mm long, longer or 
shorter than leaf. Calyx 1-2 mm long, lobes shorter 
than or equal to the tube. Standard pink to purple, 
ovate. Pod ascending to descending, terete, 20-40 mm 
long, 2-3.5 mm wide, brown to dark brown, 
indumentum of moderately dense, appressed or 
slightly spreading hairs, apex acute, shortly pointed; 
endocarp spotted. Seeds 4-10. Flowering: Nov - Feb; 
fruiting: Mar - June. Fig. 26 
Endemic to the NT. Occurs in Eucalypt savanna on 
sandy, lateritic or shale-derived soils, frequently 
associated with stony ridges and escarpments. 
Common in the DR. In the Adelaide River - Batchelor 
area, there is a form with 3-5 leaflets that are larger 
than those of the typical form (30-70 mm long, 18-50 
mm wide, terminal leaflet to 80 mm long and 70 mm 
wide). This form may have arisen from intergradation 
of I. saxicola and I. schultziana. 
