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The subterranean organs of the achlorophyllous Sciaphila polygyna (Triuridaceae) are described, depicted, and structurally explained for the first time. Unlike other Triuridaceae, the subterranean system of S. polygyna appears as a complex star-like structure of short, but thickened, roots as well as scale leaves and shoots. A complete series of sections revealed the following construction. In the axil of a scale leaf at a shoot of first order, a side shoot of second order as well as a pair of endogenous shoot-borne roots arise. This side shoot of second order also develops a scale leaf very early in ontogeny, which again gives rise to a side shoot of third order and a pair of shoot-borne roots. Other scale leaves at shoots of any order may also bear shoots and root pairs. This growth pattern occurs in a very close manner without internode elongation, resulting in the clumped, star-like appearance. The structures …