How can types be used to determine the application of names?

If the name-bearing types of two zoological names are considered to belong to the same taxon, then the two names are considered to be synonyms at the rank of that taxon. For example: the type specimens for the parasitic wasp names Trichopria aequata (Thomson, 1858) and Trichopria isis Nixon, 1980 are now considered to belong to the same species, consequently the names are synonymous and, according to the Principle of Priority (Article 23; glossary), assuming both names are not otherwise invalid, the older and valid name for this species is T. aequata. This is shown in the diagram below.

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Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith