Tardigrada

species classification - University of Michigan Museum of Zoology

list of the numbers of taxa described - Texas A&M University

classification, included taxa and references - Palaeos web site

ITIS - species information - Integrated Taxonomic Information System

taxonomic hierarchy - The Taxonomicon

IRMNG genera list

genome size - Animal Genome Size Database

genome size - Animal Genome Size Database

genome size - Animal Genome Size Database

genome size - Animal Genome Size Database