Article

In order to conserve plant diversity and ecosystems in which it coexists, in Tissemsilt provence, our work will be representing as a contribution, to the botanical knowledge of Algeria, not only at local scale, but also at the regional and national ones. We provide, here, for the first time, a preliminary inventory of the vascular plants of the culminating zone (and its surroundings) of Ouarsenis sensu stricto (or Djebel Ouarsenis). Djebel Ouarsenis which culminates at 1985m altitude (in Bordj Bounaama), owes to a whole mountain range, its current typonomy «Ouarsenis» (in the broader sense of the word), which extends over a length of 200 km, from east to west, from the Titteri mountains to those of Beni Chougrane. With this elevation, the Sidi Amar peak represents the highest peak in the northwestern Algeria (Algiers and Oran Tell Atlas). During the period 2018 to 2023, following the phytosociological methodology, which consists of carrying out floristic surveys, we carried out about a hundred surveys (126) of predetermined surface, to which added, independently, many other parallel observations. We were able to produce a catalog of more than 558 taxa, divided into 316 genera and 78 families. As for the identification of plants. It based mainly on the old floras of Algeria and/or the two neighboring countries and/or the western Mediterranean region. Then, before the synonymy was updated (as well as the chorology), it was compared with the databases currently in force. This allowed us to highlight around 40 endemic plants, and 22 new taxa for the region.