Thought previously to be a form of elongatus, which is differs from only in minor petal morphology.
"A. cuneatus is superficially similar to A. elongatus, but a conspicuous difference exists in the shape of the outer flower segments, with A. cuneatus having wedge-shaped tepals and A. elongatus having spatula-shaped tepals." (Jacobs et al. 2006; DEWHA 2008)
Rare, unknown location, apparently prolific viviparousAponogeton found only in a few streams in north and west Australia. Would make a stunning aquarium plant.
Newly described in 2005. Good aquarium plant. Available only in Australia and so far nor exported. As of this writing (2007) efforts are underway for exportation of Australian Aponogetons, but the wheels of the guvmint move (very) slowly.
Per S.W. L. Jacobs Telopea 11(2): 2006
(note: distachys has been introduced to Australia as included here to make it a practical field guide.
1.
Proliferous offshoots formed at tip of peduncle; plants rarely flowering
1. A. proliferus
1*
Proliferous offshoots not formed on plants; plants regularly flowering
2
2.
Inflorescence branched with two spikes
3
2*
Inflorescence unbranched with one spike
5
3.
Flowers white (rarely pink); tepals 1, with 13 or more veins
2. A. distachyos
3*
Flowers yellow, yellow-green, or green; tepals 2–6, 1-veined
4
4.
Tepals 6; seeds (2.6–)5.1–6.2(–7.0) mm long; leaves all floating
3. A. hexatepalus
4*
Tepals 2; seeds 2.1–3.2 mm long; leaves all submersed
4. A. lancesmithii
5.
Leaves all submersed, slightly to strongly bullate
6
5*
Leaves submersed and/or floating, not bullate
7
6.
Spathe persistent, to 2.5 cm long; inflorescence to 5.5 cm long; peduncle about same
diameter as inflorescence rachis
5. A. bullosus
6*
Spathe caducous, to 1.5 cm long; inflorescence to 34 cm long; peduncle much broader
than inflorescence rachis
4. A. lancesmithii
7.
Plants mainly producing floating leaves; floating blades mostly cordate at base; seeds
with obvious double testa
6. A. queenslandicus
7*
Plants mainly producing submersed leaves or submersed and floating leaves;
floating blades mostly obtuse, some cuneate or truncate at base; seeds with a single
testa or, if double, the second seed coat closely adhering and difficult to detect
8
8.
Submersed leaves narrow, 0.9–3 mm wide; seeds 0.7–1.4 mm long
7. A. kimberleyensis
8*
Submersed leaves broad, 5–60 mm wide; seeds 1.2–4.9 mm long
9
9.
Fruit oval and thick-coated; seed coat closely adhering to embryo and difficult to
detect, or tightly-fitting and very thin; floating leaves rarely formed
10. A. elongatus
9*
Fruit elliptic and papery; seeds with a loose outer coat, easily separated from embryo;
floating leaves commonly formed
10
10.
Seeds broadly elliptic, nearly oval, (1.1–)1.5–2.8 mm wide
