Lichenomphalia umbellifera

In Lichenomphalia umbellifera the fruit body produced by the fungal partner in the lichen is a mushroom that appears on soil. The cap is dry, in shades of light to mid brown, somewhat funnel-shaped to flattish (but then with a central depression) and with numerous radial pleats in the outer half. The cap may be up to 2 centimetres in diameter, but often is no more than half that. The gills are pale brown and run down the stem a little. The stem is pale to mid brown, up to 2 centimetres long and 2 millimetres wide.

In this lichen the fruit body is the dominant feature and the associated algal cells appear as a green mat  on the soil surface. That mat need be nothing more than a sparse green wash on the soil. Filamentous fungal cells (hyphae) wrap themselves around the algal cells.

A number of non-lichenized fungi produce similar types of fruit bodies (see Omphalina s.l.: http://canberranaturemap.org/Community/Species/20395).  To be sure that you have Lichenomphalia umbellifera check that there is a green algal mat on what is otherwise bare soil around the mushrooms.

The other species of Lichenomphalia known from the local region is the bright yellow Lichenomphalia chromacea (https://canberra.naturemapr.org/Species/5840).