Abstract
This study investigates and taxonomically interprets the morphological variation of Anthemis rigida in the Aegean region (Greece). The eligulate plants are widespread and morphologically homogeneous whereas the ligulate forms are local and more variable. Based on a morphometric evaluation of 20 characters, four different ligulate subspecies are recognized; A. rigida subsp. antri-neptuni is described here as new. All taxa share the same chromosome number of 2n = 18 and are karyologically similar. The new subspecies slightly deviates in the karyotype formula, even though asymmetry indices do not discriminate among taxa in the group. Notes on the taxonomy, geographical distribution and habitat of all ligulate subspecies are provided, together with photographs and a distribution map.