There are 30 to 36 Carissa species with 1 (4) occurring in Queensland.
They are evergreen, widely branched shrubs, trees or scrambling vines.
The glossy opposite leaves are on petioles up to 5 mm long.
Leaves, often 3 to 5 cm long, can be up to 7 cm and around 2 to 5 cm wide.
The blade can be round, oval or lanceolate with a rounded tip.
The edges are sometimes rolled under and the tip may have a mucro (abrupt point).
They can be smooth or have sparse to dense hairs on one or both surfaces.
They have white latex in the tissues.
There are usually paired thorns at the leaf bases.
They can be up to 7 or 8 cm long, simple or forked once or twice.
Green when young they become brown and woody.
Short inflorescences, with very small bracts, are terminal or axillary.
The cream to white flowers are bisexual and radially symmetric.
They are on stalks 2 to 20 mm long.
The calyx has 5 sepals up to 7 mm long that may be hairy externally.
The bases of the 5 petals are fused into a tube around 1 cm long.
It tends to bulge at the insertion of the stamens.
The flaring lobes are up to 1 cm across.
Hairs may or may not be present on either surface of the tube.
The 5 stamens are inserted near the top of the tube ( 2 -3 mm in).
The filaments are very short and the narrow anthers up to 2 mm long.
The anthers are not attached to the style head.
The ovary of 2 fused carpels has 2 locules.
The thin style holds an almost round stigma with a bilobed tip.
There is no nectiferous disc.
The fruit, up to 2 cm long, are round to oval fleshy berries.
They sometimes have a pointed tip and ripen to a shiny red or purplish red to black.
Each has 1 to 4 flattened seeds.