aestivalis is a small and discrete plant looking like to Spiranthes
spiralis, but differing by linear leaves that raise around the bottom of the stem, earlier blooming period and wet environment.
Flowers are tiny, tube-shaped, hardly fragrant and arranged in helix twisting around the stem axis. The labellum is rather elongated and indented at the edge.
This plant is very rare and can be accidentally found in full light, in marshy meadows, peat bogs or littoral dunes. This species is threatened due to rarefaction of its environment. It is protected on the whole French territory.