Rediscovery and conservation assessments of Salvia drusica (Lamiaceae) and Centaurea trachonitica (Asteraceae) in Jabal al Druze, Syria, with lectotypification of both names and the first description of S. drusica nutlet morphology

Abstract

Field surveys in Jabal al Druze, southern Syria, rediscovered Salvia drusica and Centaurea trachonitica and provided the first modern population-level documentation of both species. We provide updated information on distribution, population size, morphology, habitat, associated flora and threats, together with preliminary assessments under the IUCN Red List Categories and Criteria. Salvia drusica was rediscovered at its historical locality at Sale on 1 May 2026, nearly 84 years after Mouterde’s collection, and was recorded at 15 georeferenced occurrence points around Sale, Tlaleen and Abu Zuraik. Approximately 500 flowering mature individuals and 150 non-flowering immature plants were observed. Its minimum convex polygon EOO was approximately 14.7 km²; for assessment purposes, this was adjusted to 20 km² to equal the AOO calculated with a 2 × 2 km grid. The species occurs predominantly in cultivated land, field margins and roadsides and is exposed to ploughing, livestock grazing and potential road widening. Mature nutlets, which were unknown in the original description, were collected on 30 May 2026 and are illustrated and described here for the first time. Centaurea trachonitica was rediscovered on the western slope of Tell Shihan, north of Shahba, on 11 May 2024, nearly 82 years after Mouterde’s collection. Eight separately rooted plants, comprising two mature and six immature individuals, were documented at two occurrence points approximately 150 m apart. The known plants of each species are provisionally treated as a single subpopulation. On present evidence, S. drusica is provisionally assessed as Vulnerable under criterion D1 (VU D1), and C. trachonitica as Critically Endangered under criterion D (CR D). Lectotypes are designated for both species names. These rediscoveries highlight the conservation importance of Jabal al Druze and the need for targeted surveys, population monitoring and habitat protection.