Digitaria radicosa (J. Presl) Miq. (1857: 437)

Verloove, Filip, Gonçalves Silva, Juan J. & Leliaert, Frederik, 2024, Critical notes on grasses (Poaceae) of Madeira, Portugal, Phytotaxa 670 (1), pp. 1-17 : 3

Digitaria radicosa (J. Presl) Miq. (1857: 437)

Specimens examined: PORTUGAL. Funchal , Santa Luzia, parque, lawn, 12 September 2021, F. Verloove 14177 ( BR) ; Funchal , Jardim de Santa Luzia, plantation weed, relatively frequent, 25 April 2022, F. Verloove 14318 ( BR, MADM) .

This species is native to tropical and subtropical Asia and the Pacific. In addition, it is found as a weed in some other tropical and subtropical areas of the world, e.g. in Hawaii, Madagascar, Tanzania and Venezuela (e.g. Nozawa et al. 2017, Imada & Kennedy 2020). In Macaronesia, it is locally naturalized in the Canarian islands of La Palma ( Otto & Scholz 2009), Gran Canaria and Tenerife ( Verloove 2017). It is usually found in irrigated lawns or as a weed in ornamental plantations in parks and gardens.

Digitaria radicosa belongs to the D. ciliaris complex and is much reminiscent of it. It is, however, easily separated based on its rachis margins that are smooth (vs. scabrid). In addition, it is a slender, sprawling annual that often roots at the nodes, typically with only 2–3 racemes.

In the island of Madeira, Digitaria radicosa is naturalized in Jardim de Santa Luzia, in Funchal and should be looked for elsewhere in similar habitats.