Nematophyta

Nematophyta was a phylum of land organisms, which are probably plants (although their biochemistry is consistent with algal affinity), known to have existed from the Silurian period to the early Devonian Rhynie chert. The genus, Nematothallus was first described by Lang in 1933, who believed it was a thallose plant with tube features and sporophytes, covered by a cuticle which preserved the impressions of the underlying cells. He found several disaggregated remains of all three of these features, but none were connected to each other, leaving his construction of the phytodebris as parts of a single organism conjectural.

The lack of the clear definition of nematophytes has led to it being a wastebasket form taxon, with all occurences of tubes and cell-patterned cuticles from around the Silurian being called "Nematophytic" more as a statement than a scientifically meaningful statement.

It is difficult for Linnaean taxonomy to accomodate several fossil groups, because they often times form stem groups to modern taxa. Thus despite Strother's attempts to formalise the nomenclature of Nematothallus, the hierarchy of the class, order, and family are usually thought of as a stem group to the embryophytes, with the green algae a stem group to the Nematophytes in return. Since no reproductive or vegetative structures common to current land plants are seen, it may not be safe even to assume this relationship.