It has smooth bark, sickle-shaped to curved adult leaves, characteristically large flower buds in groups of three with a bright red operculum, bright yellow to yellowish green flowers and sculptured, bell-shaped fruit.

[4][5][3][8] Eucalyptus erythrocorys was first formally described by Ferdinand von Mueller in 1860 in Fragmenta Phytographiae Australiae.

[10] The species is a member of the sub-genus Eudesmia, a group that has stamens in four bundles each at the corner of the squarish flower.

[12] Illyarie is classified as "not threatened" by the Western Australian Government Department of Parks and Wildlife.

[7] The plant is sold commercially in seed form[13] or as tube stock[14] and is a popular species throughout Australia.

[8] It prefers a position in full sun, in well-drained soils and can be grown in containers and in coastal locations.