Animalia
Acanthocephala, Acoelomates, Annelida, Arthropoda, Brachiopoda, Bryozoa, Chordata, Echinodermata, Echiura, Gastrotricha
Fungi
Ascomycota, Basidiomycota, Zygomycota, CABI Bioscience Databases: Index Fungorum, Fungi of Poland, Introduction to the Fungi, Mushrooms of Spain, Natural Perspective: Fungus Kingdom, The Fifth Kingdom, Treasures from the Kingdom of Fungi, Zoosporic Fungi Online
Plantae
Anthocerotophyta, Bryophyta, Coniferophyta, Cycadophyta, Equisetophyta, Ginkgophyta, Gnetophyta, Hepaticophyta, Lycopodiophyta, Magnoliophyta
Protista
Bacillariophyta, Chlorophyta, Chrysophyta, Dinoflagellata, Euglenophyta, Myxomycota, Oomycota, Phaeophyta, Rhodophyta, Xanthophyta
Viruses
Complete Tospovirus Resource and Database, Index of Viruses, International Committee on Taxonomy of Viruses, Principles of Virus Architecture, The Big Picture Book of Viruses, The Influenze Sequence Database, Virus Databases Online, Virus Nomenclature, Viruses - From Structure to Biology
ARKive
Non-profit initiative of The Wildscreen Trust with photographs, movie clips, sound recordings, and brief desriptions of selected endangered and protected species of Britain and the rest of the world.
Biodiversity Explorer
Classification of all forms of life, with some photos. Has a strong South African emphasis.
BioImages - Virtual Fieldguide for UK Biodiversity
Large selection of pictures of organisms, mostly British in origin. Images are an aid to identification, showing different stages, states and views of the organisms. Search the database or follow a taxonomic tree.
BioLib
Taxonomic tree of plants and animals with a photo gallery and some checklists for the Czech Republic and Slovakia. In Czech and English.
BIOSIS Resources
Includes the Index to Organism Names, a publicly available subset of TRITON the Taxonomy Resource, and the Zoological Record Thesaurus.
Canada's Aquatic Environments
Provides comprehensive information about the aquatic habitats, animals, and plants of this country.
Canadian Version of Integrated Taxonomic Informati
Searchable database of four kingdoms: plant, animal, fungi, monera. Search by scientific or common names, English or French.
Census of Marine Life
A global network of researchers engaged in a ten-year initiative to assess and explain the past, present, and future diversity, distribution, and abundance of marine life in the oceans.
Discover Life
Information about taxonomy, natural history, distribution, abundance, and ecology of many species worldwide. Includes tools to identify, map, and database species.
Flora and Fauna of the Great Lakes
Provides access to materials from the fish, mammal, and fungus collections of the University of Michigan, USA. Includes many images of specimens.
HabitasOnline
Information on the plants, animals, and fossils of Ireland. Includes an encyclopedia of marine life of the UK. From the Ulster Museum Sciences Division.
Integrated Taxonomic Information System
Authoritative taxonomic information on plants, animals, fungi, and microbes of North America and the world.
Kingdoms Project
Project to establish web-based databases of organisms and other natural sciences subjects. Includes information about some taxonomic groups.
Lepidoptera and Other Life Forms
Taxonomic tree of mammals, insects, birds, and plants. Includes common and scientific names, publication details, references, links, general range maps, and some images. Most complete for Lepidoptera.
Mikko's Phylogeny Archive
A compilation of various phylogenetic trees representing different views of taxonomy. Includes links to other taxonomic websites.
Natural Perspective
Dedicated to the beauty and science of nature and to the joys nature brings to those who explore it. The material here is organized according to the biological principles of Taxonomy.
Natural Selection
A gateway to quality, evaluated Internet resources in the natural world co-ordinated by The Natural History Museum, London.
Nature of New England
Photos, facts, and links to information about birds, butterflies, mammals, and wildflowers of this region.
NCBI Taxonomy
Searchable and browsable taxonomy tree of organisms for which there are publicly available gene sequences.
Survey of the Plant Kingdoms
Explores plant anatomy, taxonomy, and classification, from Monera through the higher plants. Includes descriptions as well as graphics and schematics.
Tree of Life
Phylogenetic tree with information about the diversity of organisms on Earth, their history, and characteristics. An on-going multi-authored project hosted by the University of Arizona.
Utah Conservation Data Center
Database of photos and fact sheets for animals and plants occurring in this state. Includes lists of sensitive, threatened, and endangered species.
Wikispecies
Wikimedia Foundation project that aims to catalog all species.
World Biodiversity Database
A growing taxonomic database and information system that aims at documenting all presently known species (about 1.7 million). Taxonomic trees, descriptions, synonyms, literature citations, and molecular database queries.
World's Boreal Forests: Animal and Plant Spec
Fact sheets and photos for mammals, birds, trees and other plants of boreal regions.