Diagram of measurements used in descriptions A1 aerial photosynthetic part of the stem (referred to as aerial part in the descriptions of the species forming dense mats or hummocks) A2 rhizome-like stem of the species forming dense mats or hummocks B free part of the involucral bracts (notice the typically fused base) C1 leaf lamina C2 sheath-like leaf base. Details taken from Alice Tangerini’s illustrations.