Dactyloctenium is a genus of annual and perennial grasses in the family Poaceae (order Poales), described by the German botanist Carl Ludwig Willdenow in 1809. Commonly known as crowfoot grasses, the genus takes its name from the Greek daktylos (finger) and ktenion (small comb), a reference to the characteristic finger-like arrangement of the spikelets that radiate outward from the tip of each stem, resembling a crow's foot or a comb.
The genus comprises approximately 13 species distributed across tropical and subtropical Africa, Asia (from Turkey east to Taiwan and Indonesia), and Australia. The greatest diversity is found in sub-Saharan Africa, particularly in eastern and southern Africa and Madagascar, though several species extend into the Arabian Peninsula and the Indian subcontinent, where three species are recorded. A number of species have been introduced well beyond their native ranges and are now naturalised in Australia, the Americas, and southern Europe.
The most widespread member of the genus is Dactyloctenium aegyptium (Egyptian crowfoot grass or Egyptian grass), a cosmopolitan weed of disturbed ground, roadsides, and cultivated fields across the tropics and warm-temperate regions. Dactyloctenium australe (Durban grass) is native to eastern and southern Africa and Madagascar and is sometimes grown as a lawn grass. Dactyloctenium radulans (buttongrass) is endemic to Australia. The genus is closely related to Eragrostis, Acrachne, and Harpochloa, and several former Dactyloctenium species have been transferred to those genera.
Etymology
The genus name Dactyloctenium is derived from the Greek daktylos (finger) and ktenion (small comb), describing the finger-like, comb-shaped arrangement of spikelets radiating from the stem tips that gives these grasses their characteristic "crowfoot" appearance.
Distribution
Dactyloctenium is native to tropical and subtropical Africa, Asia (Turkey to Taiwan and Indonesia), and Australia, with the centre of diversity in eastern and southern Africa and Madagascar. Several species, most notably D. aegyptium, have naturalised widely in the Americas, southern Europe, and Pacific and Indian Ocean islands through human movement.
Ecology
Members of the genus are predominantly plants of open, disturbed, and seasonally dry habitats — roadsides, field margins, overgrazed grasslands, and sandy or loamy soils in tropical and subtropical climates. Dactyloctenium aegyptium is one of the most common warm-season annual weeds of cultivated ground globally, tolerating drought and full sun.
