234 EUPHORBIACEAE 
Poranthera 
PORANTHERA Rudge 
A genus of 10 species in Australia and New Zealand; 3 in the NT and 1 in the DR. 
P. microphylla Brongn. 
Annual glabrous erect herb, to 7 cm high. Stipules 
membranous, subulate, c. 1.5 mm long, sometimes 
toothed. Leaves alternate, simple, entire, discolorous, 
spathulate, 12-20 mm long, 4-6 mm wide, midrib 
prominent below. Inflorescence a compact terminal 
bracteate head-like raceme to 10 mm long. Bracts 
foliaceous, 1.5-2 mm long. Pedicels 2.5-6 mm long. 
Flowers monoecious; sepals 5, +free, linear to 
narrowly oblanceolate, white with pinkish markings; 
petals 5, +free, much smaller than sepals or obscure. 
Male flowers: sepals 0.6-0.8 mm long; stamens 5, 
free; anthers 4-locular, opening by terminal pores. 
Female flowers: ovary 3-celled, each cell with 2 
ovules, 6-lobed; styles 3, divided almost to base into 
2 linear branches. Fruit a thin-walled dehiscent 
capsule , depressed globular, c. 2 mm diam. Seeds 6, 
reddish, in shape a segment of a sphere, c. 0.6 mm 
long, alveolate; caruncle absent. Flowering and 
fruiting: Mar - July. Fig. 77 
In all mainland states and New Zealand; widespread 
though uncommonly collected across the Top End; 
scattered records in the DR from Melville Is. to 
Litchfield NP. Found in open forest. A variable taxon 
over its range and as presently circumscribed almost 
certainly includes several taxa. 
SAUROPUS Blume 
Subshrubs or perennial herbs, in the DR with annual aerial parts. Stems usually foliose throughout, rarely 
phyllanthoid. Stipules persistent. Leaf blades alternate, entire, coriaceous, almost sessile, with a strong 
central vein usually ending in a minute mucro, and with obscure secondary venation. Flowers dioecious or 
monoecious, axillary; perianth usually thick and coriaceous and lacking the hyaline margin seen in Phyllanthus. 
Male flowers with tepals in two whorls of 3, free or connate into a tube; stamens 3, usually connate into an 
androphore; disk absent. Female flowers with tepals in 2 whorls of 3, shortly connate, mostly larger than in 
the male; disk absent; ovary 3 locular with 2 ovules per locule; styles entire or bifid. Fruit a capsule (in DR), 
ovoid or ellipsoid. Seeds triquetrous, exarillate. 
A genus of c. 40 species occurring from tropical Australia to India. About 25 species occur in Australia, 
with c. 15 species in the NT and 6 in the DR. This genus was treated in the Flora of Central Australia (Jessop, 
1981) as Synostemon. 
1. —-_ Leaves COordate ......scsscssssecscscesesssssnsssesssssesscscaesencscasscscsesecesccscncncscnsecscasessnasssesecssssensceeeateres S. ditassoides 
1. .. Leaves not Cordate ........csccsssscsssssssssssrssesssssesessencscecseacnencacacascsrerecesecesesssesssesesscssscsoacsogonores 2 
2. Flowering stems leafless or with 1-3 leaves .......ss.sssessessssssesessesseesseesseessessseeseceseceneeneenenees S. ‘Darwin’ 
2. Flowering stems with numerous leaves ........sssesssessessesseesseesseesseesseessseseesscesssnnecsensseeneennes 3 
3. Leaves broad, usually <3 times longer than Wide ........seessecseseeessestestesestsseenesestencenseeneeys 4 
3. Leaves narrow, >3.5 times longer than Wide .........sscccsseceseessesssseseseseseneneseseseeteneneneneeeeneees 5 
4. Plants glabrous; leaves concolorous, margins flat ..........sssessssssesssessseesseecsseecsneessesesneensies S. ochrophyllus 
4. Plants pilose; leaves discolorous, margins recurved S. ‘Melville Island’ 
5. Leaves linear, 0.5-0.6 mm wide; tepals in male flower c. 1.5 MM 1ONG......seeeeeeeeeeseeees S. glaucus 
5. Leaves narrowly elliptic, 1.5-9 mm wide; tepals in male flowers >2 mm long S. ‘Tiwi’ 
S. ditassoides (Muell.Arg.) Airy Shaw 
throughout. Stems, leaf margins, veins and 
Phyllanthus ditassoides Muell.Arg. 
tepals hispidulous. Stipules c. 0.5 mm long. 
Leaf blades slightly discolorous, ovate, broadly 
ovate to orbicular, 4-35 mm long, 5-32 mm wide, 
A prostrate or erect several stemmed herb to 
45 cm tall. Branchlets terete, usually foliose 
