From our search in Victoria’s Alpine National Park, we suspect the rare Asplenium hookerianum (Hooker’s spleenwort) is actually much more common there than previously recognised. But more searching is needed to confirm this.
Asplenium hookerianum can be distinguished from the other ferns it occurs with in Victoria by its being fertile at a small size (c. 5 cm), with linear reproductive structures, and fronds that are twice divided with rounded frond segments.
Small plants of Asplenium flabellifolium (necklace spleenwort) can resemble Asplenium hookerianum. However, the latter has bi-pinnate (twice divided) fronds, discernible at the base of even small fronds.
Polystichum proliferum (mother shield fern) and Cystopteris tasmanica (bladder fern) have frond segments with pointed apices and round rather than linear reproductive structures. Further, Polystichum proliferum usually does not become fertile until a size bigger than Asplenium hookerianum.
Asplenium gracillimum (a hen & chickens fern) also usually does not become fertile until a size bigger than Asplenium hookerianum. The latter also differs in its frond segments being more stalked.