Passerina is a genus in the plant family Thymelaeaceae. They are ericoid bushes growing largely in fynbos and other Southern African scrub habitats. Members of the genus Passerina are ericoid shrubs or shrublets, often with a tendency to having pendulous branches. Their leaves are markedly decussate. They are concave or closely involute, lined with woolly hairs, and cling to leafy stems without being large enough to cover them. This gives the plants a characteristic plaited or corded appearance. The genus is endemic to Southern Africa, most species within South Africa, though some extend north of the border. The greatest concentration of species is in Cape fynbos, where some species are endemic to very small regions. Passerina ericoides for example occurs naturally only on the Cape Peninsula and the vicinity of False Bay. The Khoisan name gonna refers to the use of its tough bark, together with that of related plants, for binding such items as thatch. The material certainly is remarkably tough and has been used for plaiting into whip thongs. The Khoisan use of a decoction of some species for treating pain, plus the fact that many species of the Thymelaeaceae suggests that the material might be pharmacologically active, but there is no suggestion that the plants cause harm to stock. However, this harmlessness might well be for the same reason that the plants generally are of no value as forage for browsers, namely that they are unpalatable to stock.

Passerina filiformis commonly known as Bakkerbos in Afrikaans is a shrub growing up to 2 m. It is currently quite scarce in the Cape Peninsula, but a healthy community of these plants occurs on Signal Hill where it is often subjected to mist creeping over the mountain. The leaves are dark green to grayish green, heart-shaped in cross section, and the length x width is 5.5-8 x 0.6-1 mm, slightly widening towards the base. The flowering spikes are not covered by a glue-like substance. A very important characteristic of the plant is the widely obovate bract at the base of each flower, narrowing abruptly into a thin point. The bracts are normally much larger than the leaves, the length x width is ± 7.3 x 2 mm. The salmon-pink flowers are ± 6.0 mm long when pollination takes place, but they become red with age. When ignited, plants disappear in a blaze of hot flame owing to a waxy secretion on the leaves. The plants were formerly used for heating up the ovens used to bake bread. Today it is quite scarce around Cape Town, probably because of the impact of the collecting of this once abundant resource. At maturity these plants are quite ornamental and they have been cultivated in Britain and Europe since the time of Linnaeus. Plants are vigorous resprouters, they are well adapted to the Cape climate and would be suitable for reclamation plantings in areas where invasive alien vegetation has been cleared. The bark is very tough and has been used by indigenous peoples as twine. According to Laidler a decoction of this plant has been used by the Khoekhoe for the treatment of shooting pains.