Australian Tropical Rainforest Plants banner
  • Species information
  • About
  • Resources
  • Home

Zanthoxylum brachyacanthum



Botanical Name

Zanthoxylum brachyacanthum F.Muell.

Mueller, F.J.H. von (1857) Transactions and Proceedings of the Philosophical Institute of Victoria: 65. Type: In the Araucaria forests of Moreton Bay. Hill & Mueller..


Fagara brachyacanthum (F.Muell.) Engl., Die Naturlichen Pflanzenfamilien 3(4): 119(1896), Type: ?.

Common name

Yellowwood, Thorny; Thorny Yellowwood


Stem sometimes clothed in broad-based conical spines each about 5 mm long. Cambial layer quite yellow.


Leaf bearing twigs clothed in scattered sharp spines. Leaflet blade margins recurved at the apex. Leaflet blades about 35-80 x 17-30 mm on leaflet stalks about 2-6 mm long and channelled on the upper surface. Oil dots quite large, sparsely scattered and appear to be on or close to the lower surface of the leaflet blade just beneath the epidermis. Pulvinus present on the terminal leaflet but not on the lateral leaflets. Compound leaf rhachis channelled on the upper surface.


Flowers borne in tight clusters, each flower about 5-6 mm diam. Female flowers: Calyx lobes somewhat fleshy, each lobe about 0.8 x 0.8 mm. Petals fleshy, about 3.5 x 1-1.5 mm. Staminodes 4, each about 0.3-0.4 mm long. Ovary about 2 x 1 mm consisting on one carpel. Style short, somewhat obliquely attached to the apex of the ovary. Stigma globose. Ovules 2, pendulous.


Fruits brown, about 8 x 7 mm. Seed enclosed in a black sarcotesta. Seed + sarcotesta about 5-6 x 5 mm. Seeds about 5 x 4 mm. Cotyledons about 3 x 2.,5 mm. Radicle about 0.5 mm long.


Features not available.

Distribution and Ecology

Endemic to Australia, occurs in NEQ and southwards as far as north-eastern New South Wales. Known from a few localities at altitudes between 550-750 m. Grows in monsoon forest and vine thicket.





RFK Code