Home Search By Name Browse NT Flora NT Specimen Data Regional & Ecological Floras Threatened Species Introduced Species NT Species List Help page
Dichotomous key to groups of MacDonnell Ranges plants
1 Adult plants with stems that are largely woody, or if rarely pithy rather than woody (i.e. palms and grass trees) then the trunk/s greater than 10 cm wide (trees, shrubs, mistletoes and woody vines) 2
1: Adult plants with stems that are wholly herbaceous to slightly woody at very base or plants herbaceous and lacking stems (climbing and non-climbing herbs and subshrubs) 9
2 Leaves borne directly on each main stem/trunk, the live ones crowded at the apex of each stem/trunk; leaf broadening at very base and partially sheathing (encircling) the stem 3
2: Leaves all or mostly borne on branches or branchlets rather than directly on each main stem/trunk, the live ones not crowded at the apex of each stem/trunk OR leaves absent or reduced to tiny scales; leaf not broadening at very base nor sheathing (encircling) the stem 5
3 Leaves linear, less than 5 mm wide, undivided and with entire margins Grass Trees
(Xanthorrhoea thorntonii)
3: Leaves not linear, greater than 5mm wide, distinctly incised, lobed or divided into leaflets 4
4 Leaves pinnate; leaflets flat or slightly concave at base, never splitting; reproductive structure a cone Cycads (Macrozamia macdonnellii)
4: Leaves fan-shaped with incised margins (Livistona mariae), or if pinnate then most leaflets distinctly folded inwards (from margins towards centre) and sometimes splitting along the midvein towards the base (Phoenix dactylifera); flowers (and fruits) sometimes close together but never aggregated into cones Palms
5 The terminal expanded leaf on each branchlet with a sheath-like stipule that completely encloses the growing shoot prior to falling; stipules leaving an obvious scar that encircles the stem when they fall; sap milky; flowers and fruits numerous but highly modified and never exposed, being borne on the inner surface of a fleshy globular receptacle or false fruit Figs (Ficus brachypoda)
5: Not combining the above characters 6
6 Trees with leaves much reduced and scale-like, arranged in whorls encircling the branchlet joints; fruiting structure a woody cone 7
6: Not combining the above characters 8
7 Scale leaves in whorls of three; scale leaves and their decurrent bases (that completely cover the internodes) the same color; branchlets with a resinous (coniferous) odour when crushed; female fruiting cones globular with six woody scales; tree of rocky hills and ranges Cyprus Pine (Callitris glaucophylla)
7: Scale leaves in whorls of 4-17; scale leaves soon turning straw-coloured or brown and contrasting with the greener branchlet internodes; branchlets lacking a resinous (coniferous) odour when crushed; female fruiting cones barrel-shaped with numerous projections in longitudinal lines; trees of sand plains, dunefields and disturbed watercourses near Alice Springs Casuarinaceae (2 species)
8 Perianth parts (i.e. sepals and/or petals) that are 1) fused together into a cap (sometimes also a smaller second cap present) that 2) eventually falls from the mature flower bud 3) exposing numerous stamens; trees or mallees rarely less than 2 m high with woody capsular fruit and leaves that typically give off an eucalyptus odour when crushed Eucalypts and Corymbias
8: Perianth parts never fused together into a cap that falls at anthesis; perianth parts either readily recognisable, much reduced and parts not easily counted or rarely completely absent Main Dicot Key
9 Young leaves coiled from tip downwards and unfurling as they expand; sori (clusters of spore-bearing sporangia) present on the underside of mature leaves (check several leaves including the most mature) Typical Ferns
9: Young leaves not coiled from tip downwards and not unfurling as they expand, or if rarely so (Drosera) then mature plants producing flowers OR plants leafless; spores not present on the underside of mature leaves 10
10 Aquatic plants confined to semi-permanent or permanent water bodies with comparatively stable water level; all leaves fully submerged below water surface or some leaves floating on water surface, rarely a few extending just above water surface Submerged or Floating Aquatics
10: Plants of dryland situations or occurring in temporary water bodies, rarely occurring in semi-permanent or permanent water bodies; if growing in semi-permanent water then leaves neither mostly submerged nor mostly floating, at least some extending prominently above the water surface 11
11 Leaf blades (when present) with 3-many parallel longitudinal veins OR if veins not discernible with a hand lens then the lower part of the leaf partially or fully sheathing(encircling) younger inner leaves and/or the flowering stem; if leaf blades completely absent then base of the flowering stems encircled by bladeless sheaths 12
11: Leaf blades (when present) with a single midvein (with or without lateral veins), netted venation or palmate venation, OR if veins not discernible with a hand lens then leaves not sheathing; if leaf blades completely absent then bladeless sheaths also absent 19
12 Plants never producing flowers but with spore-bearing sporangia embedded in swollen leaf bases Isoetes muelleri
12: Plants bearing flowers, without spore-bearing sporangia embedded in swollen leaf bases . 13
13 Inflorescence a distinctive dense cinnamon-brown elongated spike, divided into two parts with a small gap between them, the upper male portion and lower female portion; robust perennial(to more than 2 m high) of wetlands Typha domingensis
13: Inflorescence not as above; annuals or perennials 14
14 Flowers and fruits densely packed into a solitary ovoid or hemispherical white to dark grey head 3-6 mm wide terminating each peduncle; heads surrounded by several sterile bracts shorter than the heads; peduncles with an obliquely mouthed bladeless tubular sheath at the base; small annuals (less than 15 cm high) with transverse septa in the leaves and capsular, 3-lobed fruit containing three seeds Eriocaulon (2 species)
14: Not combining the above characters 15
15 Perianth conspicuous, six parts readily counted (sometimes with the aid of a hand lens) though rarely (Commelina) one very conspicuous and five less obvious, all petaloid (white, yellow, blue, pink or purple), all sepaloid (green and transluscent turning straw-coloured), or differentiated into sepals and petals, the longest more than 2 mm long or if rarely less then leaf auricles absent and anthers with filaments Perianth Monocots (Commelina,
Juncus, Lilies, Lomandra & succulents)
15: Perianth parts absent or highly modified (as scales or bristles) and not readily seen or distinguished as a perianth (in such cases other structures known collectively as bracts are the dominant flowering structures), or if present as a more recognisable perianth (Triglochin) then inconspicuous (less than 2mm long) and leaf auricles present and anthers sessile 16
16 Perianth present though small (less than 2 mm long) and quickly deciduous; anthers sessile and each falling with a perianth segment; tiny leaf auricles present though ligule absent; fruit finally separating into segments corresponding to the three fertile carpels, the carpels with basal spurs or appearing 6-pointed when viewed dorsally; small annual wetland plants Triglochin (4 species)
16: Typical perianth parts absent or if present then highly modified (as scales or bristles) and concealed within bracts; anthers not sessile; if leaf auricles present then ligule also present; fruit not as above 17
17 Terminal cluster of flowers fully or partially enclosed by a pair of prominent erect sheathing bracts; leaf sheaths with free margins; tiny fruits splitting to release a single seed; small annuals to 6 cm high Centrolepis (2 species)
17: If flowers rarely in a terminal cluster and fully or partially enclosed by a pair of prominent erect sheathing bracts, then leaf sheaths without free margins and fruits indehiscent; plant size and longevity various (grasses and sedges) 18
18 Leaf sheaths with free often closely overlapping margins (examine younger leaves) and not (except for Bromus) forming a complete tube encircling inflorescence-bearing stems (culms); ligule present at the junction of blade and sheath on inner surface (absent only in Echinochloa); a paler wedge of tissue (collar) usually present towards leaf blade margins just above ligule; culms with nodes, usually at least some exposed, rarely all hidden within leaf sheaths; spikelets typically consisting of a pair of sterile bracts (glumes) at the base and 1-several individual flowers (florets) above that are enclosed by a pair of bracts (lemma and palea), or if ever the palea missing then spikelet with only one fertile flower; perianth represented by 2 (-3) tiny colourless scales (lodicules) on one side of the ovary; embryo position visible on external surface of fruit; various habitats including wetlands Grasses (not currently available)
18: Leaf sheaths with fused margins (examine younger leaves as sheaths sometimes split and appear free in old leaves) and forming a complete tube encircling culms; ligule absent or present in few species (seven out of 48); collar absent; culms mostly nodeless or all nodes hidden within leaf sheaths, rarely some exposed in few species (two out of 48); spikelets lacking or with up to two sterile bracts at base and consisting of several individual flowers each enclosed by a solitary bract (glume); perianth absent or represented by 3-10 bristles or scales surrounding the base of the ovary; embryo position not visible on external surface of fruit; mostly wetland species (creeks, swamps, claypans and waterholes), rarely a few species (seven out of 48) occurring on rocks or other dryland habitats away from the influence of intermittent inundation Sedges (not currently available)
19 Leaves with a long stalk terminated by four leaflets (resembling a 4-leaf clover); wetland plants never producing flowers but with spore-bearing sporangia enclosed in purse-like structures (sporocarps) at the base of the plant Marsilea
19: Leaves not resembling a 4-leaf clover; plants bearing flowers or if with spore-bearing sporangia then not enclosed in purse-like structures at the base of the plant 20
20 Plants never producing flowers but with spore-bearing sporangia fused into a stalkless 3-lobed fruit-like structure in the axils of 2-lobed scale leaves; sterile leaves (i.e. those not bearing sporangia in the axils) scale-like and unlobed; uncommon plant restricted to moist shaded rock crevices Psilotum nudum
20: Plants bearing flowers or if with spore-bearing sporangia then sporangia not fused into a stalkless 3-lobed fruit-like structure in the axils of 2-lobed scale leaves 21
21 Plants never producing flowers but with spore-bearing sporangia borne in stalked narrow terminal spikes, the whole structure resembling a small spear; leaves generally few, lanceolate, ovate or elliptic with netted venation Ophioglossum (2 species)
21: Plants bearing flowers; leaf density, shape and venation various Main Dicot Key