Aloes and Lilies of Ethiopia and Eritrea

226 IRIDACEAE
Key to the species
1. ARISTEA Ait.
The genus is easily distinguished from the other genera in
the family by the underground parts being an elongated
rhizome, rather than a corm.
The leaves are linear to lanceolate, distichous,
crowded at the base of the plant. The stems are rounded to
compressed in cross­section, sometimes winged, bearing
reduced leaves or leafless. The inflorescences have one to
many paired rhipidia (umbellate flower clusters) arranged
in panicles or crowded in fascicles on short branches.
The bracts are (within spathes) membranous or scarious.
The flowers are usually sessile, radially symmetric, blue,
each lasting one morning only, perianth twisting spirally
on fading. The tepals are basally fused for up to 1 mm,
subequal, spreading horizontally. The stamens are erect
with oblong anthers. The style is filiform, dividing into 3
short stigmatic lobes at the apex. The capsules are ovoidellipsoid
to oblong­cylindrical, or 3­lobed.
The genus is represented by about 50 species in sub­
Saharan Africa including Madagascar, with the highest
diversity in southern Africa. Two species are known to
occur in Ethiopia.
1. Flowering stem flattened and 2-winged, leafless except for 1 short subapical
leaf or leafy bract; flower clusters 1–2 (rarely 3 or 4) per stem 1. A. abyssinica
- Flowering stem rounded to weakly compressed or 2-angled, bearing 2 or more
leaves, these not subapical but mostly inserted below middle; flower clusters
several (usually more than 3) 2. A. angolensis
Aristea abyssinica
1. Aristea abyssinica Pax
The specific epithet ‘abyssinica’ refers to the former name
of Ethiopia, Abyssinia. The species was described by Pax
in 1892 from a plant collected in the border area between
Tigray and Gonder floristic regions by Schimper. It was
also known by the name A. alata Baker, which is now a
synonym.