Out-curling involucral bract tips of Heterolepis aliena catch the eye while the yellow ray florets are still concealed in bud. It is the outer, narrowly leaf-like rings of bracts that curl out. These green bracts have whitish, hairy keels in picture.
The innermost ring comprises very different bracts that lie flat on the rays. They are almost entirely membranous and brownish translucent to partly transparent.
The dark, central opening in the flowerhead indicates lengthening of the rays, causing a cavity over the disc florets allowing for their development (Manning, 2007; iNaturalist).