Further records of opuntioid cacti (Opuntieae, Opuntioideae, Cactaceae) from Tunisia with a key and updated checklist of the species of the genus Opuntia in northern Africa

Abstract

Further botanical investigations on the vascular mainly non-native flora in Tunisia, especially between 2012 and 2023, yielded numerous novelties of succulents belonging to the Cactaceae in the form of new records and or new distribution data. Opuntia phaeacantha and O. pilifera as casual aliens are here reported for the first time from the African continent. O. engelmannii and O. leucotricha are probably reported for the first time from northern Africa. These two species are considered only as adventive, at least at present. 0. tomentosa is here first reported as established in northern Africa, previously reported only as casual from Algeria. Additionally, new distributional records from Tunisia are given for O. elatior,O. monacantha, O. robusta and O. tuna. Short chorological data are given for each of the reported species, comments on their actual status was pointed out and original field photographs are provided. A diagnostic key to the naturalised species of 0puntia in North Africa is proposed together with an updated checklist and a pictorial guide.