Gymnarrhena Micrantha

The genus Gymnarrhena (Compositae) contains only one species, Gymnarrhena micrantha, a small desert annual with a prostrate rosette close to the ground 0.5 to 2.5 cm high (Figure 1). The lanceolate leaves, which under certain conditions have dentate margins, are 3 to 10 cm long. Their broad bases surround the subterranean capitula, each containing 1 to 2 relatively large achenes, which lack a pappus. ¹ They remain below the soil surface on the dead mother plant and germinate in situ (atelechory). ¹¹ Thus, the seeds are protected against seed-eaters until they germinate. From the main stem, above the subterranean capitula, 1 to 3 main lateral branches 2 to 3 cm long develop, each of which bears a terminal aerial capitulum. In each capitulum, numerous tiny, hairy achenes are formed which possess a pappus. ¹ After the death of the plant at the beginning of summer, the seeds remain within the hard inflorescence bracts (Figure 2) until the following winter, well protected from seed-eaters (mainly ants).