Ornithogalum isauricum

Description

Ornithogalum is a genus of perennial plants mostly native to southern Europe and southern Africa belonging to the family Asparagaceae. Some species are native to other areas such as the Caucasus. Growing from a bulb, species have linear basal leaves and a slender stalk, up to 30 cm tall, bearing clusters of typically white star-shaped flowers, often striped with green. The common name of the genus, star-of-Bethlehem, is based on its star-shaped flowers, after the Star of Bethlehem that appears in the biblical account of the birth of Jesus. The number of species has varied considerably, depending on authority, from 50 to 300. Ornithogalum species are perennial bulbous geophytes with basal leaves. Sensu lato, the genus has the characteristics of the tribe Ornithogaleae as a whole, since the tribe is monotypic in that sense. Sensu stricto, the genus is characterised by long linear to oblong-lanceolate (lance-shaped) leaves, sometimes with a white longitudinal band on the adaxial (upper) side, an inflorescence that is corymbose or pseudocorymbose, tepals that are white with a longitudinal green band only visible on the abaxial (lower) side, a capsule that is obovate or oblong, and truncate with six noticeable ribs in section and seeds that are globose with a prominently reticulate (net-like pattern) testa. The bulbs are ovoid with free or concrescent scales. The longitudinal band on the leaves is thought to be caused by an interruption of palisade tissue in the central portion of the leaf. This is an apomorphy that was not present in the early lineage of this clade, but is also seen in some Albuca species. When the genus is broadly circumscribed, as for example by Plants of the World Online, species are widely distributed over several continents including Africa (other than the tropics), Madagascar, Europe, and temperate Asia (as far as Afghanistan).