Pennantia is a small genus of shrubs or trees found in Australia, Norfolk Island and New Zealand. The leaves are alternate, entire or toothed, with hair tufts in the axils of the veins on the lower surface. The flowers are borne on articulate pedicels in terminal panicles, and may be either hermaphrodite or unisexual; with a calyx that is rudi mentary or small and shallowly five-lobed; five petals, white, glabrous; five stamens; filaments filiform. The ovary has one locule containing one ovule, the style short or obsolete, the stigma three-lobed. The fruit is a single-seeded small drupe, the seed hard and three-sided. The genus is named for Thomas Pennant (1726–1798), the British zoologist and antiquary.
Often called ‘the rarest tree in the world’, P. baylisiana (W.R.B. Oliv.) G.T.S. Baylis is known in the wild only as a single female specimen on the Three Kings Islands, New Zealand. With broad glossy leaves it is a handsome ornamental, and as such is cultivated in New Zealand. In the United Kingdom it is available from County Park Nursery, Essex, but their assessment is that it will only tolerate a degree or two of frost (County Park Nursery 2008).