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AUSTRALIAN BIOLOGICAL RESOURCES STUDY
FLOODPLAIN FLORA
A flora of the coastal floodplains
of the Northern Territory, Australia
I. D. Cowie, P. S. Short & M. Osterkamp Madsen
Parks & Wildlife Commission of the Northern Territory
FLORA OF AUSTRALIA SUPPLEMENTARY SERIES NUMBER 10
Extract: Pandanaceae
PANDANACEAE
Trees, shrubs or vines, often bearing stout adventitious prop roots in the lower part of the
stem. Leaves alternate, in 3 (4) ranks, appearing spirally arranged because of the spiral
growth of the stem tip, simple; base sheathing; blade narrow, long, xeromorphic, parallelveined, glabrous, usually spiny on midrib and margins. Flowers unisexual, dioecious, small,
numerous, reduced, usually borne in a terminal spadix subtended by (1) several large spathes
or in several racemosely arranged spadices. Staminate flowers crowded, often not sharply
delimited from each other; stamens 1–many; filaments distinct or often connate into more or
less distinct bundles (phalanges). Pistillate flowers with 1–many carpels; carpels distinct or
often connate into phalanges, often incompletely sealed; stigmas sessile; ovules 1–numerous
per carpel. Fruit of crowded but distinct unicarpellate drupes or more often of polydrupes
corresponding to the phalanges of carpels, or sometimes berry-like or woody.
An Old World family of three genera and c. 800 species, mostly in the tropics.
PANDANUS Parkinson
Trees or shrubs, sometimes semiaquatic or epiphytic; prop roots with prominent root caps
often present. Leaves crowded at apex of branches, longitudinally folded. Male
inflorescences caducous, branched, bracteate. Male flowers: stamens numerous, usually in
umbellate or racemose arrangements on stemonophores, sometimes inserted directly on
rachis. Female inflorescences consisting of 1 or more globular to cylindrical heads (cephalia)
almost enclosed by bracts. Female flowers: ovaries closely packed, 1- or more-celled; cells
1-ovulate. Fruit globular to cylindrical, of many free, crowded drupes or drupes connate into
1–many phalanges (polydrupes). Screw-palms.
A genus of c. 700 species found in the Old World tropics between West Africa and Hawai’i.
The genus in northern Australia is in need of further work. St.John recognised ten species in
NT, several of which were subsequently reduced to varieties by Stone (1978, includes
references to papers by St.John).
Taxonomic references: Stone (1978), Wilson (1992).
Drupes orange-red when ripe, fused into groups, with 5–14 (24) drupes in each polydrupe............... P. spiralis
Drupes pale yellow when ripe, mostly free...................................................................................P. aquaticus
P. aquaticus F.Muell.
Trees to 6 m tall, often in clumps; prop roots present. Leaves long-attenuate, to 1 m long,
2–11 cm wide at base; midrib and margins with antrorse spines diminishing in size towards
the apex and absent at base. Male inflorescence of c. 9 racemosely arranged spadices; each
spadix of numerous, racemosely arranged stemonophores 6–13 mm long; bracts foliaceous,
12–65 cm long. Male flowers pale yellow, reduced to stamens; anthers 4–15 per staminate
bundle, c. 3 mm long. Female inflorescence solitary, unbranched, capitate; bracts numerous
and crowded, to 1 m long. Fruit of many free unicarpellate drupes crowded into a globular
head c. 15 cm diam. Drupes pale yellow, clavate, 30–40 mm long, 8–11 mm wide, irregularly
5- or 6-angled in upper half. Seed c. 6 mm long. Flowering: June–Nov. Fruiting: Feb.–Aug.
Plate 39, Fig. 44 (Dunlop 8730).
Kimberley region of WA, Top End of NT, and NW Qld. A rheophytic species usually at sites
of permanent water and often found fringing billabongs or along permanent watercourses; on
sand or clay.
The drupes float in water and are eaten by black bream and freshwater turtles. Heated leaves
are used by some Aboriginal clans for treating sores (Wightman et al., 1994).
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Pandanus
PANDANACEAE
P. spiralis R.Br.
Trees to 8 m tall, often in small clumps; prop roots often present. Leaves long-attenuate, to
2 m long, 4–7 cm wide at base; midrib and margins with antrorse spines diminishing in size
towards the apex. Male inflorescence of c. 11 racemosely arranged spadices; each spadix
3.5–5 cm long and of numerous racemosely arranged staminate bundles which are 4–9 mm
long; bracts foliaceous, 12–65 cm long. Male flowers white; anthers to 14 per bundle,
c. 2 mm long. Female inflorescence pendulous, solitary, capitate; bracts numerous and
crowded, to 1 m long. Fruit of many polydrupes crowded into a globular head c. 20 cm diam.
Polydrupes orange-red, strong-smelling, 5–7 cm long, 4–10 cm wide, woody; sides
irregularly angled; apex flat to slightly concave; base slightly fleshy and fibrous. Drupes
5–14 (24) per polydrupe, subequal, 3–5-angled; faces smooth to prominently grooved; suture
lines between lateral drupes complete to absent; apices shallowly concave to prominently
pyramidal, with or without radial sutures from stigma to sinus. Seed fusiform, c. 25 mm long.
Flowering: Apr.–July. Fruiting: June–Oct. Plate 40, Fig. 44 (Dunlop 5952).
Widespread in N Australia (WA, NT, Qld). Grows in poorly drained areas in eucalyptdominated communities, along creeks, in dune swales and on the margins of floodplains; on
sand or clay. As accepted here, P. spiralis is a widespread and variable species. Variation
from within just one population (as demonstrated by the series Dunlop 5952–5957) is
sufficient to account for several of the ‘species’ described by St.John (1962), including
P. arnhemensis H.St.John, P. darwinensis H.St.John and P. thermalis H.St.John. Much work
is needed before variation in the group is properly understood.
The strong-smelling, slightly fleshy but fibrous base of the polydrupe is attractive to flying
foxes which probably serve to disperse the fruit.
Aboriginal people have a wide variety of uses for the plant. The leaves are frequently used
for weaving; the soft bases of the young leaves, seeds, the bases of the ripe phalanges and the
central axis which bears the phalanges are all commonly eaten; the bases of young leaves, the
apex of the stem and prop roots are in some cases used as medicine; and the stems are used
for rafts, carrying fire and as didgeridus by some clans (Levitt, 1981; Smith & Wightman,
1989; Wightman & Smith, 1989; Wightman et al., 1991; Marrfurra et al., 1995; Yunupingu
et al., 1995).
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