The flat base of the calyx of Apatesia helianthoides continues in the five broad and unequal sepal lobe bases. Abrupt turning up of the lobes constitutes the perimeter of the about circular flower base, after which they become narrow oblongs, here with faintly sinuate marginal curving before a rounded or slightly pointed tip.

The flat, green blades of these lobes appear useful in shielding the fragile young petals in their midst, here newly released in a range of subtle colours and still cohering erectly (Le Roux, et al, 2005; Leistner, (Ed.), 2000; Smith, et al, 1998; Eliovson, 1990; Herre, 1971; iNaturalist).