Résumé
The authors present the results of more than 5 years of observations of orchids in the western Tell Atlas of Tiaret (Algeria). These taxa were inventoried at the regional level, according to subjective sampling, and the ecological conditions at each of the stations collected. The identification of taxa was made through different flora, with a taxonomic conception based on morphological criteria using "morpho-species". Twenty taxa belonging to 7 different genera were identified, dominated by Ophrys and Anacamptis. New data regarding the biogeography of these taxa are provided and several taxonomic difficulties encountered are highlighted. This study made possible to compare local data with those found in some publications on orchids in Algeria.