Phaulostephanus [SEP] parent taxon
Phaulostephanus
Phaulostephanus is an extinct genus from the ammonoid family Stephanoceratidae, which is part of the ammonitid superfamily Stephanoceratoidea, that lived during the early Middle Jurassic.
"Phaulostephanus" is a small serptenticone with a generally subcircular to subquadrate whorl section, slightly sinuous ribbing, and tubercles that if present are weakly developed. Primary ribs are sharp, divide about mid flank into prominent and moderately sharp secondary ribs. The aperture of the macroconch has a broad ventral collar preceded by a constriction. That of the microconch is flanked by lappets
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