Wastebin taxon

From Freepedia

Wastebin taxon (also called a wastebasket, or dustbin taxon) is a term used in taxonomic circles that refers to a taxon that has the sole purpose of classifying organisms that don't fit anywhere else. The familiar category Invertebrates is an "everything-else" category left when vertebrates have been selected out: "invertebrates" include animals from all the phyla save Chordata and share no distinctive ancestry.

Examples of wastebin taxa include Simia, Rhynchocephalia, Carnosauria, Megalosaurus and Thecodontia. Sometimes, during taxonomic revisions, the wastebin taxa can be salvaged after doing thorough research on its members, and then imposing tighter restrictions on what continues to be included. Such techniques "saved" Carnosauria and Megalosaurus. Other times, the taxonomic name contains too much unrelated "baggage," to be successfully salvaged. As such, it is usually dumped in favour of a new, more restrictive name (for example, Rhynchocephalia, or Thecodontia), or abandoned altogether (for example, Simia).