Alectryon tomentosus (SAPINDACEAE) Hairy Alectryon

Plants to Plant

A common small tree to 15 m in all types of rainforest. The large seeds are carried by birds, but mostly propagate in the vicinity of a large specimen. The adult trees do not supress germination. Young trees can be quite thick around the adults. A very hardy plant, able to survive in hard conditions, poor soils and drought. Other common names Woolly Rambutan, Hairy Bird’s Eye. Fruit is a brown hairy capsule, 1-3 lobed, opens to reveal edible red aril and shiny black seed. The fleshy aril is quite pleasant tasting, though there is not much of it. The seeds are cyanide collectors, so will be toxic. They are unlikely to be toxic if swallowed whole, but could be if chewed or crushed.


Leaves are compound (parapinnate), basal leaflets much smaller than terminal ones. Leaflets 4-8, margins usually regularly toothed, upper surface smooth or finely hairy, lower surface usually more hairy, petiole 10-30 mm, petiolules 1-2 mm.

Leaflets increasing in size outwards from the petiole. Photo: Robert Whyte


Flowers are creamy pink to reddish from May to August. Although this flower has appeared on Monday, 29 January 2007.

Flowers closeup. Photo: Robert Whyte


The name Alectryon is derived from Greek word for rooster. This refers to the cockscomb appearance of a ridge on the fruit. Alectryon was a Greek youth. One night, while having sex with Aphrodite, Ares put Alectryon by his door to guard them. He fell asleep, and Helios, the sun, walked in on the couple. Aries turned Alectryon into a rooster, which never forgets to announce the arrival of the sun in the morning. Tomentosus from Latin tomentosus thickly and evenly covered with short, more or less, curled or curved matted hair, in reference to the hairy leaves and young shoots.

Photo: Robert Whyte

Host Plant

Food for Green Catbird Ailuroedus crassirostris and various butterflies. Host plant for the caterpillar of the Hairy Line-Blue Erysichton lineata. The females are brown on top with a large white patch on each forewing, and a blue sheen near the hinges and the hindwings each have a black eye-spot at the tornus. Both sexes have a small tail at the hindwing tornus. The male adults are blue on top. Along with other Alectryon sp. host to larvae of Large Purple Line-blue Nacaduba berenic), Small-tailed Line-blue Prosotas felderi, Glistening Blue Sahulana scintillata and Pencilled-blues Candalides spp. These all feed on juvenile foliage and flower buds.

New growth pinky brown-green. Photo: Robert Whyte


The tree is host to the Leptocoris tagalicus bug. Carroll-Loye Biological Research shows that with only slight changes the bug could shift its focus to the introduced environmental weed Balloon Vine Cardiospermum grandiflorum.

Painting by Janet Hauser shows Balloon Vine alongside Alectryon tomentosus for Scott Carroll of Carrol-Loye Biological Research.