Identification of ferns:
Sorus & indusium
![](../assets/img/content/fern/fern_sori_n_indusium_ex_2.png)
Sori of some species are naked and not covered by any indusium (exindusiate).
They can be covered by a false indusium, a reflexed extension of the blade margin.
Others are covered by a true indusium (indusiate)