Australian Tropical Rainforest Plants - Online edition

Pycnarrhena novoguineensis Miq.


Vine
Click/tap on images to enlarge
Flowers. CC-BY J.L. Dowe
Flowers on stem [not vouchered]. CC-BY J.L. Dowe
Leaves and fruits. © CSIRO
Leaves and fruit. © CSIRO
Scale bar 10mm. © CSIRO
10th leaf stage. © CSIRO
Cotyledon stage, hypogeal germination. © CSIRO
Vine stem bark and vine stem transverse section. © CSIRO
Family

Miquel, F.A.W. (1868) Annales Musei Botanici Lugduno-Batavi 4 : 87. Type: Nova-Guinea, A. Zippelius. Holo: L.

Common name

Common Milk Vine; Vine, Common Milk

Stem

Vine stem diameters to 3 cm recorded. Concentric rings of included bark visible in transverse sections of the stems.

Leaves

Leaf blades about 14-25 x 4.5-11 cm, petioles about 1.5-3.5 cm long, pulvinus well developed. Lateral veins forming distinct loops inside the blade margin. Oak grain in the twigs.

Flowers

Male flowers: Sepals 6, +/- orbicular, adaxial surface concave, about 1.5-2 mm diam. Petals +/- crumpled, about 1 x 1 mm. Stamens about 10, each about 0.6 mm long (i.e. filament + anther).

Fruit

Fruits subglobose, asymmetrical or pyriform, about 13-18 x 14-15 mm. Seeds broadly reniform, about 11-14 x 8-10 mm. Testa very thin. Cotyledons thick, about 11-12 x 7-8 mm, dimorphic, one cotyledon much larger than the other in each seed. Radicle about 1-2 mm long held beside the cotyledons.

Seedlings

About 6 or 7 hairy cataphylls produced before the first true leaves. First true leaves elliptic, apex abruptly acuminate, base obtuse. Midrib slightly depressed on the upper surface. At the tenth leaf stage: leaf blade elliptic, about 10 x 4 cm, apex acuminate, base attenuate, midrib depressed on the upper surface. Lateral veins forming definite loops well inside the blade margin. Terminal bud clothed in pale hairs. Seed germination time 42 to 48 days.

Distribution and Ecology

Occurs in CYP and NEQ. Altitudinal range from near sea level to 200 m. Grows in gallery forest and lowland rain forest. Also occurs in New Guinea.

Synonyms
Pycnarrhena australiana F.Muell., The Victorian Naturalist 3: 61(1886), Type: Queensland, Endeavour River; W. Persieh 668, 580 & 704. Syn: MEL. Bellenden Ker Ra. 1881, G.H.H. Karsten. Syn: MEL. Pycnarrhena sayeri Diels, Das Pflanzenreich Heft 46: 55(1910), Type: Queensland, Trinity Bay, 1886, W.A. Sayer. Holo: B. Iso; MEL.
RFK Code
2103
Copyright © CSIRO 2020, all rights reserved.