''Geissoloma'' is a genus of
flowering plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...
s in the
monotypic
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...
family Geissolomataceae, native to the
Cape Province
The Province of the Cape of Good Hope ( af, Provinsie Kaap die Goeie Hoop), commonly referred to as the Cape Province ( af, Kaapprovinsie) and colloquially as The Cape ( af, Die Kaap), was a province in the Union of South Africa and subsequen ...
of
South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...
.
The plants are
xerophytic
A xerophyte (from Greek ξηρός ''xeros'' 'dry' + φυτόν ''phuton'' 'plant') is a species of plant that has adaptations to survive in an environment with little liquid water, such as a desert such as the Sahara or places in the Alps or th ...
evergreen shrubs and are known to accumulate
aluminum
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It has ...
. It is sometimes called guyalone in English.
Description
''Geissoloma marginatum'' is a low evergreen shrub of ½-1¼ m high, covered in overlapping large, leathery, simple, scale-like, opposite leaves in four rows along the stems. It has very small stipules on the petioles. Flowers are bisexual, subtended by bracts, and have four red to pinkish petaloid sepals, four petals partially united, eight stamens, and four carpels. The fruit is a capsule with four seeds.
''Geissoloma marginatum'' is the only species in the family.
Phylogeny
Recent phylogenetic analysis resulted in the following tree.
References
Monotypic rosid genera
Flora of South Africa
Crossosomatales
{{Rosid-stub