Tardigrada
/ˌtɑːdɪˈɡreɪdə
/plural noun Zoology
A small phylum that comprises the water bears.The recently published Ecdysozoa hypothesis suggests a closer relationship of the Scalidophora, Nematode, Nematomorpha, Tardigrada, Onychophora, and Arthropoda....
- Other ecdysozoan phyla include Nematoda, Tardigrada, and Onychophora; this classification thus removes onychophorans from the Arthropoda and makes them an outgroup.
- However, on both morphological and molecular grounds it seems that two groups that are sometimes given phylum rank, the Onychophora and the Tardigrada, are the closest living relatives of the arthropods.
Origin
Modern Latin (plural), from Latin tardigradus, from tardus 'slow' + gradi 'to walk'.