A pseudorhiza is a root-like underground portion of the stipe. The pseudorhiza typically tapers towards its base. Often, the pseudorhiza is narrower than the stipe base (which may be somewhat expanded) and the surface texture of the pseudorhiza is also usually different to that of the above-ground portion of the stipe. Where a pseudorhiza is present, it usually sits firmly in the soil.

It is quite common for fruit-bodies of Australian agarics to have a significant portion of the stipe buried in the soil, particularly in sandy soil. When this occurs a pseudorhiza is usually lacking. The buried portion usually does not sit firmly in the soil, and the fruit-body can be very easily pulled out of the soil. Once adhering soil has been brushed off, there is no clear differentiation in shape or texture between the above-ground and below-ground portions of the stipe (and the stipe base may be quite bulbous). The few ambiguous cases are coded as pseudorhiza present or absent. See also Stipe base shape.

Choose this state if: a pseudorhiza is absent.