This member of the Euphorbiaceae family was given this name by Werner Rauh and Günther Buchloh in 1967. It is found in central to northern Madagascar, growing in sandy or other well drained soil with some water and some to lots of sun. The caudex, most significant on younger plants, can grow to six centimetres or more, the spiny branches can reach 50 centimetres in length. The flowers are from greenish over pale yellow to salmon. Strangely enough, many sites claims this is a Mexican species. It is NOT, it do originate from Madagascar! Might be confused by Euphorbia aaron-rossii, A.H. Holmgren and N.H. Holmgren, although the appearance are real distinguish.
The genera name; Euphorbia dates back to the first century BC, where King Juba II of Mauritania used it in a reference to his doctor, Euphorbos, and that name was kept as a generic name by Carl von Linnaeus. The species name for William Ross, a botanical collector. A larger plant by PalmBob.

