The cypselas are relatively large and flattened, blackish in color, with ample hairs, and remain below the soil surface after the plant has died.

[7] The aerial flower heads have some semblance to a hedgehog and the hard, dry plants hurt the naked foot if stepped upon.

[7] Gymnarrhena is most related to Cavea, but few morphological features would support this assignment, other than both having two types of flower heads and sharing a tendency towards dioecism.

Other asterids that have flower heads with only one floret are Corymbium, Hecastocleis shockleyi, Stifftia uniflora and Fulcaldea laurifolia, but these are pentamerous and hermaphrodite.

In 1857, a second species, G. balansae was distinguished by Ernest Cosson and Michel Charles Durieu de Maisonneuve, but it is doubtful this form from Algeria is sufficiently different.

John J. Skvarla, Billie Lee Turner, and their colleagues in 1977 agreed that Gymnarrhena has some traits in common with the Cynareae but a pollen type that cannot be found in the Inuleae tribe.

Kåre Bremer in his 1994 book Asteraceae: Cladistics & Classification included Gymnarrhena in the Cichorioideae, but without clarifying its position in this tribe.

[7] Gymnarrhena micrantha is now considered the sister group of Cavea tanguensis, who together constitute the tribe Gymnarrheneae and the subfamily Gymnarrhenoideae.

[3][7] Based on recent genetic analysis, it is now generally accepted that the Pertyoideae subfamily is sister to a clade that has as its basal member the Gymnarrhenoideae, and further consists of the Asteroideae, Corymbioideae and Cichorioideae.

Gymnarrhena is known from North Africa, such as Algeria and Egypt, the Middle-East, such as Sinai, Israel, Jordan, Siria, Kuwait, eastern Saudi Arabia, Qatar, the United Arab Emirates, Iraq, Iran and Pakistan (Balochistan).

After the first rain, which usually occurs the next winter, the bracts and pappus on the aerial flowerheads unfold, and the cypselas are dispersed by the wind, while many are gathered by ants.

[7] Gymnarrhena is one of few species that grows where the sand has blown out from under tar tracks in Kuwait after the Gulf War, a strong confirmation of its ability to colonize disturbed habitat quickly.

At Khirbet Faynan, in the southern Jordanian desert, Gymnarrhena grows on slag piles containing copper and lead and accumulates these heavy metals.