Atractocarpus merikin, commonly known as the mountain gardenia or merikin, is a plant in the Rubiaceae family endemic to northeast Queensland, Australia.
Atractocarpus merikin is an evergreen shrub growing up to in height, occasionally, with separate male and female plants. The dark green leaves are arranged in opposite pairs and may be up to long by wide. They are narrow at the base and broadest near the far end of the blade, and the base is auriclulate and sessile or almost sessile.
The inflorescences may consist of panicles, fascicles or solitary flowers, and are produced in the leaf axils. The white fragrant flowers have 5 petals and measure about diameter. The calyx lobes are about long, the corolla tube about long.
The fruit is an orange, pink or reddish drupe between long and wide, containing numerous brown patelliform (i.e. like a shallow dish) seeds.
Flowering occurs from October to February, fruits ripen from July to February.
This species was first described in 1902 by the English born Australian botanist Frederick Manson Bailey in his book The Queensland Flora, in which he gave it the name Gardenia merikin. In 1999 the Australian botanist Christopher Francis Puttock transferred the taxon to the genus Atractocarpus, which is the current combination.
The genus name Atractocarpus is created from the Ancient Greek words atractos (spindle) and karpos (fruit). It refers to the shape of the fruit of the type species, Atractocarpus bracteatus. The species epithet merikin is the local indigenous name for the plant.
Merikin grows in well developed rainforest from Mt Spurgeon (source of the Mossman River), to the Tully River, at altitudes from around to .
This species is listed by the Queensland Department of Environment and Science as least concern., it has not been assessed by the IUCN.