Secotium [SEP] parent taxon
Secotium
Secotium is a genus of fungi in the family Agaricaceae. The members of this genus are closely related to ordinary "Agaricus" mushrooms, but do not open out in the usual way; this has given rise to the term "secotioid" for such mushrooms in general. They are thought to form an evolutionary link between agarics and gasteroid fungi (whose spores are enclosed in a pouch-like structure). "Secotium" is a widespread genus, with species that are predominantly found in warm and arid regions.
Taxon in disguise
In bacteriology, a taxon in disguise is a species, genus or higher unit of biological classification whose evolutionary history reveals has evolved from another unit of similar or lower rank, making the parent unit paraphyletic. This happens when rapid evolution makes a new species appear radically different from the ancestral group, so that it is not (initially) recognised as belonging to the parent phylogenetic group, leaving the latter an evolutionary grade.
While the term is from bacteriology, parallel examples are found throughout the tree of