Australian Tropical Rainforest Plants - Online edition

Dianella atraxis R.J.F.Hend.


Grass
Herb (herbaceous or woody, under 1 m tall)
Shrub (woody or herbaceous, 1-6 m tall)
Click/tap on images to enlarge
Flowers. © G. Sankowsky
Flowers. © G. Sankowsky
Leaf bases. © G. Sankowsky
Habit and leaves. © G. Sankowsky
10th leaf stage. © CSIRO
Cotyledon stage, hypogeal germination. © CSIRO
Family

Henderson, R.J.F. () Flora of Australia 45: 476. Type: Queensland, Kuranda, 31 Jan. 1962, L.J.Webb & J.G.Tracey 5695; holo: BRI.

Common name

Dianella; Lily, Northern Flax; Northern Flax Lily

Stem

Grows to a height of 1-1.5 m but often flowers and fruits when smaller.

Leaves

Leaf blade about 35-100 x 2-4 cm, closed sheath ('petiole') about 19-21 cm long above the sheathing base. Margins finely toothed and similarly the midrib on the underside of the leaf blade. Venation longitudinal and parallel.

Flowers

Inflorescence arising from the centre of the plant and often attaining a height of 1 m or more above the ground. Tepals in two similar whorls. Outer tepals (sepals) about 6-7 mm long. Inner tepals (petals) about 5-6 mm long. Stamens six, filaments with a yellow swelling just below the anther. Anthers about 3-4 mm long. Ovules about 6-8 per locule. Style filiform, stigma minute.

Fruit

Fruits globular, about 6-8 mm diam. Seeds black, about 2.6-3.5 mm long, testa smooth, minutely areolate to minutely colliculate. Embryo tear drop shaped.

Seedlings

Seed remaining attached to the seedling by a thread-like appendage. First leaves longitudinally channelled, base sheathing the stem and giving the seedling a fan-like appearance. At the tenth leaf stage: leaves basal, produced one after another out of the base of the previous leaf. Margin finely serrate with numerous small projecting teeth. Venation longitudinal and parallel to the midrib. Midrib finely serrate on the underside of the leaf blade. 'Petiole' sheathing, about 4.5 cm long. Leaves produced in two rows in one plane (distichous). Seed germination time 71 days.

Distribution and Ecology

Probably endemic to Queensland, occurs in CYP and NEQ. Altitudinal range from near sea level to 500 m. Grows in well developed lowland and upland rain forest.

Natural History & Notes

A large clump forming plant with blue flowers. It is slowly being introduced to cultivation.

RFK Code
3355
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