The Taxonomic Hierarchy

The taxonomic hierarchy is a method of grouping together living organisms that share common features. The basis of the system in use today was formulated by Swedish biologist Carl Linnaeus (1707-1778).

The hierarchy starts with the largest groups and goes down to specific species. Using the Indian Elephant as an example:-

DomainEukaryaOrganisms with a complex cell structure
PhylumChordataOrganisms with a backbone
ClassMammaliaPlacental animals that suckle their young
OrderProboscideaAnimals with a proboscid trunk
FamilyElephantidaeElephantine Mammals
SpeciesMaximusIndian Elephant

Given that there are of thousands of genera and millions of species, the table below shows the hierarchy down to Sub-Order level only.

Bacteria Cyanophyta Blue-green algae
Schizomiceta Photo-synthesising Bacteria
Archaea Methanogenia Intestinal bacteria
Thermoacidiphilia Bacteria from hot springs
Halophilitia Marine bacteria
Eukarya Protoctista Rhodophyta Solenoporacaea Red Algae
Corallinacaea Marine colonial organisms
Chlorophyta Green Algae
Rhizopoda Single-celled organisms that move through pseudopoda
Chrysophyta Flagellates
Pyrrophyta Dinoflagellates
Protozoa Foraminifera Marine micro-organisms with a calcareous shell
Radiolaria Marine micro-organisms with a siliceous shell
Ciliata Marine micro-organisms with a chitinous shell
Bacillariophyta Diatoms
Myxomycota Plasmodial slime moulds
Acrasiomyota Cellular slime moulds
Fungi Zygomycota Parasitic fungi
Ascomycota Yeasts & Truffles
Basidiomycota Mushrooms puffballs etc
Mycophycomycota Lichens
Deuteromycota Penicillin
Plantae Bryophyta Hepticae Liverworts
Anthocerotae Hornworts
Musci Mosses
Tracheophyta Psilopsida The first land plants
Lycopsida Club mosses
Sphenopsida Horsetails
Phyllicopsida Ferns
Gymnospermopsida Pteridospermales Seed Ferns (extinct)
Cycadeoidales Cycads
Ginkgoales Ginkgoes
Cordaitales Primitive Trees (extinct)
Voltziales Trees similar to Araucaria (extinct)
Coniferales Conifers
Angiospermopsida Magnoliidae dicots
Liliidae monocots
Animalia Porifera Sponges
Archeocyathida Extinct colonial organisms
Cnidaria Scyphozoa Jellyfish
Hydrozoa Anenomes
Anthozoa Rugosa Corals with 4 primary septa
Scleractina Corals with 6 primary septa
Tabulata Tabulate corals
Bryozoa Marine colonial organisms
Brachiopoda Shellfish
Nematoda Roundworms
Platyhelminthes Turbellaria Planarians
Trematoda Flukes
Cestoda Tapeworms
Annelida Oligochaeta Earthworms
Polychaeta Lugworms
Hirudinea Leeches
Mollusca Monoplacophera Primitive mollusc with bilaterla symmetry
Polyplacophora i.e. Barnacles
Scaphopoda Scaphopods
Bivalvia Shellfish
Gastropoda Snails slugs
Cephalopoda Tetrabranchiata Nautiloidea Nautiloids
Ammonoidea Ammonites
Dibranchiata Cuttlefish squid octopus
Arthropoda Arachnida Spiders scorpions mites
Cirripedia Barnacles
Merostomata Eurypterids
Insecta Beetles flies etc
Crustacea Shrimps crabs lobsters
Trilobata Trilobites
Chilopoda Centipedes
Diplopodia Millipedes
Echinodermata Starfish sea urchins brittlestars
Chordata Enteropneusta Extinct wormlike organisms
Pterobranchia Extinct colonial organisms
Graptolithina Graptolites
Agnatha Jawless Fish i.e. Lampreys Hagfish
Placodermi Armoured fishes
Acanthodii First fish with jaws
Chondrichthyes Cartilageous Fish i.e. Sharks & Rays
Osteichthyes Dipnoi
Actinopterygii Bony Fish
Teleostei Lungfish
Crossopterygii Extinct group of fishes from the Devonian
Amphibia Labyrinthodonta Extinct group of amphibians from the late Palaeozoic/early Mesozoic
Leptospondyli Extinct group of amphibians from the Palaeozoic
Lissamphibia Frogs Toads
Anthracosauria Extinct reptile-like amphibians
Reptilia Anapsida Extinct group of primitive reptiles
Archosauria Chelonia Turtles
Dinosauria Dinosaurs
Pterosauria Flying Reptiles
Crocodilia Crocodiles
Lepidosauria Lizards
Squamata Snakes
Euryapsida Extinct group of reptiles from the Mesozoic
Ichtiopterygia Extinct group of marine reptiles
Synapsida Extinct mammal-like reptiles from the Permo-Triassic
Aves Birds
Mammalia Prototheria Monotreme Mammals
Metatheria Marsupial Mammals
Eutheria Placental Mammals

Site Map Top
[Research Tools]