Conostylis crassinerva is a rhizomatous, tufted, perennial, grass-like plant or herb up to in diameter. The leaves are flat, long and wide and
glabrous or with soft, feather-like hairs. The flowers are arranged in head-like clusters with many flowers on a flowering stalk long with leaf-like
bracts at the base of each flower and 4, shorter bracts at the base of the inflorescence. The
perianth is yellow, turning reddish as it ages, long with loosely woolly hairs on the outside and shortly woolly-hairy inside. The
anthers are about long and the
style long. ==Taxonomy and naming==