74 FABACEAE 
12-72 mm overall; stipels 6-7 mm long; /eaflets 
narrowly elliptic, lanceolate or rhomboidal, base 
cuneate, apex acute to obtuse; basal leaflets c. 2/3 
length of terminal, 13-54 mm long, 7-23 mm wide, 
L/W 1.4-2.5; terminal leaflet 22-110 mm long, 13-42 
mm wide, L/W 1.7-2.9. Inflorescence racemose or 
paniculate, interrupted, to 300 mm long; bracts 
caducous, subulate, 7-9 mm long. Pedicels 11-17 mm 
long; bracteoles absent. Calyx 2-3 mm long; lobes 4, 
2-3 times as long as tube, upper lobe bifid. Corolla 
pale mauve, minutely papillose; standard shortly 
clawed, obovate-orbicular, 3-5 mm long; wings 
shortly clawed, shallowly lobed; keel clawed. Upper 
stamen adhering shortly to base of sheath, free above. 
Style short. Pod yellow-green to brown, 15-23 mm 
long, 3-4 mm wide, densely covered with hooked 
hairs, also septate glandular hairs, sticky, both margins 
equally constricted; articles 3-6, disarticulating 
readily, elliptic, flattened, undulate, 3.5-5 mm long. 
Seeds pale brown, elliptic, flattened, 1.8-2.8 mm long, 
1.3-2 mm wide. Flowering and fruiting: most months. 
Fig. 22 
Native to tropical America but now pantropical in 
distribution. Widespread in tropical Australia. A weed 
of disturbed places. 
D. trichostachyum Benth. 
A prostrate annual herb, often forming dense mats. 
Vegetative parts with patent or adpressed white simple 
hairs, leaves often glabrous. Stipules brown, 3.5-6 mm 
long, attenuate. Leaves pinnately 3-foliolate or 
1-foliolate; rachis to basal leaflets 2-18 mm, 2-24 mm 
overall; leaflets obcordate to reniform, 3.5-16 mm 
long, 3-18 mm wide, L/W 0.7-1.1, base rounded or 
cordate, apex emarginate. Inflorescence sparse, to 200 
mm long, with white simple hairs on the rachis; 
flowers solitary at bracts; bracts caducous, c. 1.5 mm 
long. Pedicels filiform, 3-10 mm long, with minute 
hooked hairs; bracteoles absent. Calyx 1-1.8 mm long, 
with minute hooked and long simple hairs; lobes 5, 
3-5 times as long as tube, upper pair shortly connate. 
Corolla purple; standard not clawed, orbicular, c. 1.5 
mm long, + emarginate; wings and keel shortly 
clawed. Pod yellow-brown, straight or slightly curved, 
10-12 mm long, 2-2.5 mm wide, glabrous or 
occasionally with minute hooked hairs, upper margin 
entire, lower margin lobed 1/3-1/2 width of pod; 
articles 1-5, 2:5-3 mm long. Seeds mottled black and 
olivaceous, or dark brown or olivaceous, shape 
variable, 1.2-2 mm long, 1.2-1.5 mm wide. Flowering 
and fruiting: Feb - June. Fig. 22 
Endemic to and widespread in northern Australia. 
Relatively common in the DR. On low, seasonally wet 
areas, often on sandy soils or adjacent to floodplains. 
Desmodium 
*D. triflorum (L.) DC. 
Prostrate annual herb. Vegetative parts sparsely 
hairy with white simple and minute hooked hairs. 
Stipules brown, adnate to lower part of leaf rachis, c. 
3.5 mm long. Leaves pinnately 3-foliolate, rachis to 
basal leaflets 4-10 mm, 6-12 mm overall; leaflets 
obcordate or orbicular, 2-12 mm long, 2-11 mm wide, 
L/W 0.9-1.3, usually emarginate. Flowers in axillary 
fascicles of 3 or 4. Pedicels 3-8.5 mm long. Bracts 
persistent; bracteoles absent. Calyx c. 3 mm long. 
Corolla purple to almost white; standard c. 4 mm 
long. Ovules c. 4. Pod brown, 7-17 mm long, c. 2.5 
mm wide, with long hooked hairs; articles 2-4, 
indehiscent, c. 2.5 mm long, c. 2.5 mm wide. Seeds 
olivaceous, reniform, c. 2.2 mm long, c. 1.5 mm 
wide. Flowering and fruiting: late Wet and early 
Dry season. Fig. 22 
Pantropical; in Australia in the NT and Qld. A 
frequent weed in lawns. 
D. velutinum (Willd.) DC. 
Anerect annual shrub to 1.5 m tall. All parts (except 
corolla and pod) densely hairy with simple white 
patent hairs. Stipules 3-7 mm long, cordate, 
acuminate. Leaves 1-foliolate; rachis 8-34 mm long; 
stipels c. 4 mm long; /eaflets dorsiventral, ovate to 
elliptic, 42-135 mm long, 30-100 mm wide, L/W 1.3- 
1.4, venation prominent below, base cordate, apex 
obtuse or rounded, + apiculate. Inflorescence crowded, 
to 230 mm long; bracts persistent, setaceous, c. 3 mm 
long. Pedicels 2-3 mm long; bracteoles absent. Calyx 
4-5 mm long; lobes 4, subequal, c. 2 times as long as 
tube, upper lobe + bifid, lower lobe longer and 
narrower. Corolla pink-purple; standard not clawed, 
obovate, 6 mm long; wings and keel clawed. Pod 
brown, 16-18 mm long, 2.5-3 mm wide, densely hispid 
with simple and hooked hairs, upper margin entire, 
lower margin shallowly lobed; articles 4-5, 
disarticulating readily, c. 3 mm long, venation 
obscure. Seeds pale yellow, oblong-reniform, 1.8-2.7 
mm long, 1.3-2 mm wide. Flowering: Mar; fruiting: 
Apr - June. Fig. 22 
Widespread, occurring in Africa, Madagascar, 
Malesia and in Australia, where it is known only 
from the Alligator Rivers Region and Mary River 
area. Grows in dry monsoon forest on well drained 
soils. 
D. ‘Darwin’ 
A prostrate annual herb. Stems with dense patent 
yellowish strigose simple hairs; leaves with sparse 
adpressed white simple hairs. Stipules brown, 5-7 mm 
long, attenuate. Leaves pinnately 3-foliolate or 1- 
