Fabronia pilifera Hornsch.
Common names: hairy fabronia
This delicate epiphytic moss is frequently encountered in woodlands or savanna areas of South Africa.
Fabronia pilifera is a tiny, greenish moss that grows in thin, flat mats. The stems are long, creeping, with short branches and crowded leaves. The leaves are pressed against the stem when dry, except for the leaf tips which tend to bend outwards, and erect to spreading when wet.
Leaves are mostly ovate (egg-shaped) and range from 0.8 to 1.2 mm long. They have long, clear leaf tips or awns, irregularly toothed upper margins and weak midribs.
The cells of the upper leaf lamina are rhomboidal, whereas the alar cells (cells at the corners of the leaf), form a distinct group, quadrate to oblate in shape.
The hairy fabronia has male and female organs in separate clusters on the same stem. The erect to somewhat curved stalk that bears the capsule, is 6 to 10 mm long.
Its yellow-brown capsules are erect, cup-shaped, constricted below the mouth when dry and 1.0 to 1.2 mm long. As the teeth around the mouth of the capsule are paired, they appear broad. The lid of the capsule is cone-shaped with a short and oblique beak. The spores are small, round and papillose.
The conservation status of South African bryophytes has not been determined yet, but Fabronia pilifera is widespread and frequently encountered throughout the region and therefore is not of conservation concern.
Distribution and habitat
Fabronia pilifera is the most common species of Fabronia in southern Africa and found in the Limpopo, North West, Gauteng, Mpumalanga, Free State, KwaZulu-Natal, Western Cape and Eastern Cape provinces of South Africa, as well as Botswana, Swaziland and Lesotho. It has not been reported from the arid and semi-arid regions of the Northern Cape and Namibia. The species is also known from western, eastern, central and southern Africa, as well as Reunion.
The plants seem to prefer drier, open woodlands or savanna where it grows mostly on bark of tree trunks and branches, but also on rock or soil over rock or at the base of trees. It is found at altitudes from 15 to 2 100 m.
Derivation of name and historical aspects
The moss family Fabroniaceae comprises 5 genera, all found in southern Africa, of which Fabronia is the largest with 62 species. The genus is almost cosmopolitan with approximately 30 species recognized in Africa, of which four occur in the Flora of southern Africa (FSA) area.
Fabronia was named after the Florentine administrator, Giovanni Valentino Mattia Fabroni, by Giuseppe Raddi, an Italian cryptogamic botanist, in 1808. Raddi later named the liverwort genus Pellia after Fabroni’s son Leopoldo Pelli Fabroni, a lawyer (Meagher 2011).
Fabronia pilifera was originally described by the German botanist, Christian Friedrich Hornschuch, in 1841. It is based on a specimen collected at Windvogelberg near Cathcart in the Eastern Cape Province by Johann Franz Drège, a professional plant collector (Glen & Germishuizen 2010).
The specific epithet pilifera, refers to the distinctly long, transparent hair-points of the leaves, a distinguishing feature of the species. The relatively short teeth, restricted to the upper margins of the egg-shaped leaves, will also help to identify the species.
The species frequently grows in association with mosses of the family Erpodiaceae and the genus Syntrichia Brid., as well as lichens. It is found in all the bryofloristic regions of southern Africa except the Karoo-Namib Region (Van Rooy & Van Wyk 2010) and belongs to the Afromontane Grassland Element, a group of mosses mostly distributed in the Grassland and Savanna biomes (Van Rooy & Van Wyk 2011).
Because of the proximity of sex organs on the same stems and branches, sporophytes (spore-bearing generations) are common in most populations.
In the drier savanna areas, Fabronia pilifera only grows on the southern aspect of tree stems and branches, where it is cooler and moist for longer. It is, therefore, a reliable and easy way to determine direction in the veld. Records of other local uses of this moss are lacking.
Growing Fabronia pilifera
The hairy fabronia has very specific habitat requirements and will be difficult to cultivate. However, in indigenous gardens like the Pretoria National Botanical Garden, the green mats on the southern aspect of tree trunks and branches, consisting mostly of Fabronia pilifera, are attractive features of the woodland and large shade trees in the parking areas.
- Glen, H.F. & Germishuizen, G. (compilers). 2010. Botanical exploration of southern Africa, edition 2. Strelitzia 26. South African National Biodiversity Institute, Pretoria.
- Meagher, D. 2011. An etymology of Australian bryophyte genera. 2 — Mosses. Muelleria 29(1): 33–61.
- Van Rooy, J. & Van Wyk, A.E. 2010. The bryofloristic regions of southern Africa. Journal of Bryology 32: 80–91.
- Van Rooy, J. & Van Wyk, A.E. 2011. The bryofloristic elements of southern Africa. Journal of Bryology 33: 17–29.
Jacques van Rooy
National Herbarium: Biosystematics Research & Biodiversity Collections
Plant Type: Epiphyte, Moss
SA Distribution: Eastern Cape, Free State, Gauteng, KwaZulu-Natal, Limpopo, Mpumalanga, North West, Western Cape
Gardening skill: Challenging