APPENDIX
E
C L A S S I F I CAT I O N O F L I F E
This appendix presents a taxonomic classification for the
major extant groups of organisms discussed in this text; not
all phyla are included. The classification presented here is
based on the three-domain system, which assigns the two
major groups of prokaryotes, bacteria and archaea, to
separate domains (with eukaryotes making up the third
domain).
DOMAIN BACTERIA
t
Proteobacteria
t
Chlamydia
t
Spirochetes
t
Gram-Positive
Bacteria
t
Cyanobacteria
DOMAIN EUKARYA
In the phylogenetic hypothesis we present in Chapter 28, major clades of eukaryotes
are grouped together in the four “supergroups” listed in bold type below and on the facing
page. Formerly, all the eukaryotes generally called protists were assigned to a single kingdom,
Protista. However, advances in systematics have made it clear that some protists are more
closely related to plants, fungi, or animals than they are to other protists. As a result, the
kingdom Protista has been abandoned.
Excavata
t Diplomonadida (diplomonads)
t Parabasala (parabasalids)
t Euglenozoa (euglenozoans)
Kinetoplastida (kinetoplastids)
Euglenophyta (euglenids)
“SAR” Clade
t Stramenopila (stramenopiles)
Chrysophyta (golden algae)
Phaeophyta (brown algae)
Bacillariophyta (diatoms)
Appendix E Classification of Life
Korarchaeota
t
Euryarchaeota
t
Crenarchaeota
t
Nanoarchaeota
t Alveolata (alveolates)
Dinoflagellata (dinoflagellates)
Apicomplexa (apicomplexans)
Ciliophora (ciliates)
t Rhizaria (rhizarians)
Radiolaria (radiolarians)
Foraminifera (forams)
Cercozoa (cercozoans)
E–1
APPENDIX E
Archaeplastida
t
t
t
t
Rhodophyta (red algae)
Chlorophyta (green algae: chlorophytes)
Charophyta (green algae: charophytes)
Plantae
Phylum Hepatophyta (liverworts)
Nonvascular
Phylum Bryophyta (mosses)
v plants (bryophytes)
Phylum Anthocerophyta (hornworts)
Phylum Lycophyta (lycophytes)
Seedless vascular
Phylum Monilophyta (ferns, horsetails,v plants
whisk ferns)
Phylum Ginkgophyta (ginkgo)
Phylum Cycadophyta (cycads)
Gymnosperms
Phylum Gnetophyta (gnetophytes)
Seed
Phylum Coniferophyta (conifers)
plants
Phylum Anthophyta (flowering
v Angiosperms
plants)
v
DOMAIN ARCHAEA
t
Various alternative classification schemes are discussed in
Unit Five of the text. The taxonomic turmoil includes debates
about the number and boundaries of kingdoms and about the
alignment of the Linnaean classification hierarchy with the
findings of modern cladistic analysis. In this review, asterisks
(*) indicate currently recognized phyla thought by some systematists to be paraphyletic.
Classification of Life
v
DOMAIN EUKARYA, continued
t Amoebozoa (amoebozoans)
Myxogastrida (plasmodial slime molds)
Dictyostelida (cellular slime molds)
Tubulinea (tubulinids)
Entamoeba (entamoebas)
t Nucleariida (nucleariids)
t Fungi
*Phylum Chytridiomycota (chytrids)
*Phylum Zygomycota (zygomycetes)
Phylum Glomeromycota (glomeromycetes)
Phylum Ascomycota (ascomycetes)
Phylum Basidiomycota (basidiomycetes)
t Choanoflagellata (choanoflagellates)
t Animalia
Phylum Porifera (sponges)
Phylum Ctenophora (comb jellies)
Phylum Cnidaria (cnidarians)
Medusozoa (hydrozoans, jellies, box jellies)
Anthozoa (sea anemones and most corals)
Phylum Acoela (acoel flatworms)
Phylum Placozoa (placozoans)
Lophotrochozoa (lophotrochozoans)
Phylum Platyhelminthes (flatworms)
Catenulida (chain worms)
Rhabditophora (planarians, flukes, tapeworms)
Phylum Nemertea (proboscis worms)
Phylum Ectoprocta (ectoprocts)
Phylum Brachiopoda (brachiopods)
Phylum Rotifera (rotifers)
Phylum Cycliophora (cycliophorans)
Phylum Mollusca (molluscs)
Polyplacophora (chitons)
Gastropoda (gastropods)
Bivalvia (bivalves)
Cephalopoda (cephalopods)
Phylum Annelida (segmented worms)
Errantia (errantians)
Sedentaria (sedentarians)
Phylum Acanthocephala (spiny-headed worms)
Ecdysozoa (ecdysozoans)
Phylum Loricifera (loriciferans)
Phylum Priapula (priapulans)
Phylum Nematoda (roundworms)
Phylum Arthropoda (This survey groups arthropods into a
single phylum, but some zoologists now split the arthropods
into multiple phyla.)
Chelicerata (horseshoe crabs, arachnids)
Myriapoda (millipedes, centipedes)
Pancrustacea (crustaceans, insects)
Phylum Tardigrada (tardigrades)
Phylum Onychophora (velvet worms)
Deuterostomia (deuterostomes)
Phylum Hemichordata (hemichordates)
Phylum Echinodermata (echinoderms)
Asteroidea (sea stars, sea daisies)
Ophiuroidea (brittle stars)
Echinoides (sea urchins, sand dollars)
Crinoidea (sea lilies)
Holothuroidea (sea cucumbers)
Phylum Chordata (chordates)
Cephalochordata (cephalochordates: lancelets)
Urochordata (urochordates: tunicates)
Cyclostomata (cyclostomes)
Myxini (hagfishes)
Petromyzontida (lampreys)
Gnathostomata (gnathostomes)
Chondrichthyes (sharks, rays, chimaeras)
Actinopterygii (ray-finned fishes)
Actinistia (coelacanths)
Vertebrates
Dipnoi (lungfishes)
Amphibia (amphibians: frogs,
salamanders, caecilians)
Reptilia (reptiles: tuataras, lizards, snakes,
turtles, crocodilians, birds)
Mammalia (mammals)
v
APPENDIX E
Classification of Life
Appendix E Classification of Life
Unikonta
E–2