Wastebasket taxon

Examples

There are many examples of paraphyletic groups, but true "wastebasket" taxa are those that are known not to, and perhaps not intended to, represent natural groups, but are nevertheless used as convenient groups of organisms. The [obsolete] kingdom Protista (see below) is perhaps the most famous example. Wastebasket taxa are often old (and perhaps not described with the systematic rigour and precision that is possible in the light of accumulated knowledge of diversity) and populous.

• In 2022, the Pteromalidae (a Hymenoptera (wasp) family in the superfamily Chalcidoidea long considered polyphyletic) was split into 24 families.
• The Flacourtiaceae, a now-defunct family of flowering plants – the Angiosperm Phylogeny Group has placed its tribes and genera in various other families, especially the Achariaceae and Salicaceae.
• The obsolete kingdom Protista consisted of all eukaryotes that are not animals, plants, or fungi, leaving to the protists all single-celled eukaryotes.
• The Tricholomataceae is a fungal group, at one point composed of the white-, yellow-, or pink-spored genera in the Agaricales not already classified as belonging to the Amanitaceae, Lepiotaceae, Hygrophoraceae, Pluteaceae, or Entolomataceae.
• Carnosauria and Thecodontia are fossil groups, banded together back when the limited fossil record did not allow for a more detailed scheme.
• Condylarthra is an artificial clade into which ungulate mammals not clearly within Perissodactyla or Cetartiodactyla were traditionally shoved. Many of these groups, like Meridiungulata or Protungulatum, may not represent laurasitherian mammals, while others like phenacodontids have been clearly established as early odd-toed ungulates.
• The order Insectivora has traditionally been used as a dumping ground for placental insectivorous mammals (and similar forms such as colugos), usually aligned with carnivorans, ungulates, and bats. While the core components (moles, shrews, hedgehogs, and their close relations) do in fact form a consistent clade, Eulipotyphla, that is part of Laurasiatheria with the aforementioned clades, other mammals historically placed in the order have been found to belong to other branches of the placental tree: tree shrews and colugos are euarchontans related to Primates and sometimes grouped in Sundatheria, while tenrecs, golden moles, and elephant shrews are all afrotheres, probably forming the clade Afroinsectiphilia. Both of these clades have at times been accused of being wastebasket taxa themselves, grouping superficially similar animals in Euarchonta and Afrotheria, respectively, but they have been more strongly supported by genetic studies.
• Vermes is an obsolete taxon of worm-like animals. It was a catch-all term used by Carl Linnaeus and Jean-Baptiste Lamarck for non-arthropod invertebrate animals.
• The genus Mamenchisaurus is sometimes considered a wastebasket taxon for large, long-necked dinosaurs.