Named for the German botanist Dr Besser.

Perennial, cormous, tunicate herb. Leaves linear, flat or rounded, sheathing. Flowers open bellshaped. Inflorescence a several-flowered umbel, terminal. Tepals 3+3, fused basally. Stamens 6, fused together forming a cup, and attached to the tepal tube. Ovary ovoid, short stalked, stalk fused to tepals by 3 flanges. Fruit a capsule. Seeds numerous, black.

1 species cultivated and sometimes grown in Australia as a spring-flowering bulb on well drained soils.

2 species from Mexico.

Cormous plants with an umbel, anthers fused into a cup and the stalked ovary fused to the tepals.

Source: Conran, J. (2005). Themidaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 5. Flowering plants. Monocotyledons. The identification of garden and cultivated plants. University of New South Wales Press.