Like most species in this genus, cryptantha muricata
is a bristly plant; calyces, stems and leaves all have a covering of stout, white hairs, in addition to thinner, softer hairs. Some of the leaf bristles are thickened at the base. Stems are thick and stout, and grow taller than most other cryptanthas, over 3 feet. Plants branch readily, mostly above the middle. Stems and leaves are grey-green to yellow-green in color.
Flowers are produced as an elongated cluster, the heads alternating along the stem though all are concentrated at one side. They are angled upwards (ascending). Flowers are similar in appearance to many other cryptantha species, with a narrow (around 0.15 inches) corolla opening to five small white lobes, yellow at the base. There are several varieties, differing in corolla width, growth form and nutlet characteristics.