Microsorum.
Division Pteridophyta > Order Polypodiales > Family Polypodiaceae.
There are about 50 species in the genus Microsorum (with a large number of synonyms) but its limits are uncertain.
Some feel that it should be split into 2 genera based on the frond divisions and soral arrangement.
Eight species are found in Australia.
The ferns are epiphytic or grow on rocks but some will grow in soil.
They have long or short creeping rhizomes with scattered or dense scales.
Fronds may have long or short stalks or none at all.
They can be shades of green (light, dark or yellowish), bluish or blackish.
Texture varies from thin to leathery.
Frond appearance varies between species.
A single plant can have both simple and lobed or divided leaves on it.
Sterile and fertile fronds are similar.
Fronds can be simple (ovate, obovate, lanceolate or linear), variously lobed or pinnatifid (lobe divisions
do not reach the midrib), pinnate or trifoliate (with 3 leaves).
When lobed there can be from 1 to 30 pairs of lateral lobes.
Frond edges can be simple or wavy and sometimes extend down onto the stalk.
Veins can be distinct or immersed and obscured, on 1 or both surfaces.
Lateral veins may be obvious or indistinct. Veins usually form networks.
Sori can be scattered randomly on the underside of the fronds, in 1 or 2 rows on either side of the
midrib or irregular rows between the veins.
Sori are rounded or slightly elongated, up to 7 mm across, rarely coalesce and have no indusium.
They can be superficial or sunken into the frond with a corresponding faint or marked (up to 2 mm high)
bump on the upper surface.
J.F.
