Briggs and Johnson, Desmodadus (Restionaceae) 
229 
Descriptions of new species 
1. Desmodadus lateriticus B.G. Briggs & L.A.S. Johnson, sp. nov. 
A D. myriodadus combinatione characterum sequentium distinguitur: apex vaginae 
culmorum pilis longis (1-3 mm longis) patentibus albisque ciliatus; spiculae 
masculinae anguste ellipsoideae, 3.0-6.5 mm longae; flores femineae tepalis nullis; 
vaginae glumaeque herbaceae vel bruneolae. 
Type: Western Australia: 30 km NNW of Gin Gin on Brand Hwy (31°08'S 115°46'30"E), 
28 Sep 1984, B.G. Briggs 7439 & L.A.S. Johnson 6 (holo NSW; iso CANB, K, MO, 
PERTH). 
Caespitose, forming small, dense, many-culmed tussocks. Culms repeatedly 
branched, erect, terete to semi-terete, glabrous or pilose with long hairs, often 
longitudinally furrowed, smooth or finely striate or minutely tuberculate, to 50 cm tall, 
0.5-1.2 mm diam., internodes numerous; culm branches of male plants commonly 
sinuous-erect, females more flexuose and tangled. Basal sheaths short, 3-8 mm long. 
Culm sheaths appressed, green to dark red-brown, glabrous or villous, 4-7.5 mm long, 
truncate, apex fringed by long (1-3 mm) spreading white hairs; lamina 2-3(-5.5) mm 
long. Male spikelets borne singly or less often in pairs, sessile, axillary at 5-10 
successive upper nodes, narrow-elliptic, 3.0-6.5 mm long; 3-7-flowered, glumes 3-8, 
ovate to lanceolate, acute, 1.6-3.7 mm long, yellow to light brown, glabrous or apically 
villous, mucro 0.3-1.0 mm long. Female spikelets borne singly at upper nodes, 
ellipsoid, 4.5-6.0 mm long; l-(2-3)-flowered, glumes 3-5, ovate, acuminate, 2.3-6.0 mm 
long, green to pale yellow, usually villous towards apex, mucro 0.4-2.0 mm long. Male 
flowers: tepals 5, scarious, narrow-lanceolate to linear, acute, ± equal in length or inner 
tepals occasionally shorter, 1.5-3.3 mm long; anthers 1.0-1.3 mm long. Female flowers 
lacking tepals. Nut narrow ellipsoid, 2 mm long, dark brown with pale lateral lines, 
stipitate, the style base persistent as a short apical beak. (Fig. lg-lj). 
The epithet is from the Latin later, lateris, a brick, referring to the frequent occurrence 
of the species on soils that include lateritic gravel. 
Distribution: occurs in Western Australia from north of Geraldton south to the Regans 
Ford-Mogumber area and east to Cunderdin. (An isolated population is reported near 
Williams [Meney, Pate & Hickman 1999] but this should be rechecked cf. D. quiricanus). 
Locally occasional to abundant on laterite in heath or open shrubland, frequently on 
lateritic ridges. Killed by fire. 
Conservation status: not at risk. 
Distinguished from D. myriodadus (Fig. la-lc) by the long (1-3 mm), spreading white 
hairs fringing the apical margin of culm sheaths, the narrow ellipsoid male spikelets 
3.0-6.5 mm long, absence of tepals in the female flowers, sheaths and glumes green or 
light brown. D. myriodadus has the apical margin of culm sheaths glabrous or fringed 
with very short felted hairs, the male spikelets broader (ovoid-ellipsoid) and mostly 
shorter (3-4 mm long), tepals present in the female flowers, shorter broader nuts and 
sheaths, glumes and dry culms mostly golden brown. 
Selected specimens examined: Western Australia: Irwin: Murchison R., Oldfield 6 (MEL14902); 
Moresby Range, 3.9 km E of Hwy 1 at 21.7 km N of Geraldton (5 km N of White Peak Rd), 14 Aug 
1991, Briggs 8884a & Johnson 6 (NSW, PERTH), 8884c 9 (NSW, PERTH); 31 km W of Three Springs, 
W end of Nebru Rd at junction with Moorlaby Rd, 30 Sep 1984, Briggs 7515 & Johnson 6 (NSW, 
PERTH), 7517 9 (NSW, PERTH); Green Head-Coorow Rd, 0.8 km E from Brand Hwy, 17 Jun 1997, 
Davis 3319 9 (PERTH); 11 km S of Cataby on Brand Hwy, 13 Apr 1989, Krauss 132 & Howitt 9 
(NSW, CANB, PERTH); Darling: 7 km SW of Mt Lesueur, 26 Sep 1976, Briggs 6365 6 (NSW, 
PERTH); 16.5 miles [25 km] WNW of Mogumber, 23 Sep 1966, Briggs 855 9 (NSW, K, L, PERTH, 
