Australian Tropical Rainforest Plants - Online edition

Alectryon reticulatus Radlk.


Shrub (woody or herbaceous, 1-6 m tall)
Tree
Click/tap on images to enlarge
Leaves and fruit. © CSIRO
Scale bar 10mm. © CSIRO
10th leaf stage. © CSIRO
Cotyledon stage, epigeal germination. © CSIRO
Family

Radlkofer, L.A.T. (1891) Sitzungsberichte der Mathematisch-Physikalischen Classe der k. b. Akademie der Wissenschaften zu Munchen 20 : 255. Type: New Guinea, Islands of the Gulf of Papua, before 1886, collector unknown; holo: M. Fide S. T. Reynolds (1991).

Stem

Usually grows into a small tree but also flowers and fruits as a shrub.

Leaves

Compound leaves with about 3-7 leaflets. Compound leaf petiole swollen at its junction with the twig. Compound leaf rhachis convex on the upper surface. Leaflet blades about 5.5-7 x 2-2.5 cm, leaflet stalks about 0.2-0.4 cm long. Terminal buds clothed in prostrate light brown hairs. Lateral veins forming loops (sometimes indistinct) inside the blade margin. Leaflet stalks with a ridge down the middle on the upper surface and a groove on either side.

Flowers

Panicle about 3.5-11 cm long, pedicels to 3 mm long. Flowers about 2-3.5 mm diam. Calyx (perianth) saucer-shaped, lobes about 0.5-1 mm long, glabrescent. Petals absent. Stamens 5, inserted inside the disk, filaments about 0.5 mm long, anthers about 2 mm long.

Fruit

Fruits glabrous, 8-16 x 8-14 mm. Calyx persistent at the base. Style remnants lateral on the fruit. A single longitudinal rib can often be seen encircling the fruit but the fruit does not rupture along this line. Fruit ruptures transversely in the equatorial region as a result of the expanding aril. Seeds about 6 mm long. One cotyledon +/- enveloped by the other. Aril granular, deep red, surface rugose, covering about 2/3-3/4 of the seed.

Seedlings

Cotyledons thick, about 10-12 x 4-5 mm, irregularly curved and twisted. One cotyledon much thicker than the other. Cotyledons with a spur or tooth towards the base on one side. First pair of leaves simple or trifoliolate, the lateral leaflets with smooth margins and the middle leaflet with lobed margins. At the tenth leaf stage: leaf compound with 4 or 6 coriaceous leaflets and ending in a tip which projects about 3-5 mm beyond the point of attachment of the terminal pair of leaflets. Compound leaf rhachis with a ridge on the upper surface and very narrowly winged. Lower pair of leaflets stalked, upper pair of leaflets sessile. Leaflet blades elliptic, apex acuminate, base oblique; leaf blade tough and leathery, midrib and main lateral veins raised on the upper surface. Terminal bud clothed in brownish hairs. Seed germination time 42 to 60 days.

Distribution and Ecology

Occurs in CYP, NEQ, CEQ and southwards as far as south-eastern Queensland. Altitudinal range not known but probably from near sea level to 300 m. Grows in monsoon forest and the drier rain forests. Also occurs in New Guinea.

Synonyms
Alectryon unilobatus S.T.Reynolds, Austrobaileya 1: 475(1983), Type: Queensland, Pascoe River, 1977, L. J. Webb & J. G. Tracey 13123; holo: BRI.
RFK Code
1142
Copyright © CSIRO 2020, all rights reserved.