Multivariate analysis of essential oil compositions of thirteen Hypenia species revealed the presence of two taxonomic clusters. Cluster I included three species belonging to section Densiflorae in addition to H. subrosea and H. aristulata, and showed the highest percentages of α-muurolol (5.85 ± 3.08%). In Cluster II, which contained eight species belonging to section Laxiflorae, the major discriminant constituents were (E)-caryophyllene (7.09 ± 4.88%), germacrene D (18.1 ± 11.4%), and bicyclogermacrene (6.65 ± 1.19%). All essential oils showed a predominance of sesquiterpenes, such as spathulenol (4.5-31.6%), caryophyllene oxide (2.2-14.4%) and selin-11-en-4α-ol (0-34.8%). Furthermore, identical clusters were revealed by multivariate analysis of chemical constituents based on carbon skeletons, as well as on 18 morphological leaf characters of the species studied
Hypenia; Lamiaceae; essential oil; chemical variability; chemotaxonomy; multivariate analysis