Cyperus longus
From LSJ
Ξένοις ἐπαρκῶν τῶν ἴσων τεύξῃ ποτέ → Bene de extero quid meritus exspectes idem → Hilf Fremden und dereinst wird Gleiches dir geschehn
Latin > Greek
Wikipedia EN
Cyperus longus is a species of sedge known by the common names of sweet cyperus and water rush in Africa, or in Britain galingale (a variant name of galangal, an unrelated plant).