Melichrus is a small genus of shrubs in the family Ericaceae (order Ericales), endemic to eastern Australia. The genus was first formally described in 1810 by the Scottish botanist Robert Brown in his landmark work Prodromus Florae Novae Hollandiae et Insulae Van Diemen, and the name Melichrus means "honey-coloured", though Brown did not explain the precise reference.
Plants in the genus range from low-lying, procumbent forms to erect shrubs. The branchlets are pubescent and bear prominent leaf scars. Leaves are narrowly egg-shaped, more or less sessile, and crowded at the ends of branches with parallel striations on the lower surface. Flowers are produced singly in the leaf axils, often partly hidden within the leaf bases, and are borne on very short stalks. The corolla is fleshy and forms a distinctive bell-shaped (rotate) or urn-shaped (urceolate) tube, with five tufts or a ring of erect glandular hairs near the base; the lobes are valvate in bud, ovate, and bear scattered long hairs. A thick, fleshy annular nectary is present. The ovary has four to six locules, each containing a single ovule, and the fruit is a drupe with a fleshy mesocarp surrounding a hard endocarp.
Accepted species are distributed across Queensland, New South Wales, Victoria, and the ACT, with additional undescribed specimens attributed to the genus from Western Australia. The two most widespread and well-known members are Melichrus urceolatus, which bears white to yellow-green urn-shaped flowers, and Melichrus procumbens, commonly called "jam tarts", noted for leaves with long-ciliate margins. The genus is placed within the subfamily Epacridoideae of Ericaceae.
Etymology
The genus name Melichrus is derived from Greek and means "honey-coloured". It was coined by Robert Brown in 1810 when he formally described the genus, but Brown did not explain the particular feature or characteristic he intended the name to reference.
Distribution
Melichrus is endemic to Australia, with the bulk of accepted species distributed across eastern Australia — Queensland, New South Wales, Victoria, and the Australian Capital Territory. Additional undescribed specimens assigned to the genus have been collected from Western Australia. The genus shows a strong association with the eastern seaboard flora region.
Taxonomy Notes
Melichrus was first formally described in 1810 by Robert Brown in Prodromus Florae Novae Hollandiae et Insulae Van Diemen, one of the foundational works of Australian botany. It is placed in the subfamily Epacridoideae of the family Ericaceae, within the order Ericales. The Australian Plant Census (as at November 2024) recognises six formally described species and six additional undescribed specimens provisionally assigned to the genus.
