Placodontiformes [SEP] parent taxon
Placodontiformes
Placodontiformes is a clade of sauropterygian marine reptiles that includes placodonts and the non-placodont "Palatodonta". It was erected in 2013 with the description of "Palatodonta". Placodontiformes is the most basal clade of Sauropterygia and the sister group of Eosauropterygia, which includes all other sauropterygians.
Phylogeny.
Below is a cladogram from Neenan "et al." (2013) showing the position of Placodontiformes within Sauropterygia:
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