A large phylum of worms with slender, unsegmented, cylindrical bodies, including the roundworms, threadworms, and eelworms. They are found abundantly in soil and water, and many are parasites.
- ‘For example, both the Nematoda and Platyhelminthes contain obligate parasites as well as free-living species.’
- ‘The hexagonal arrangement in both adults and larvae of the internal armature in the buccal apparatus may be plesiomorphic, a shared character with Nematoda and Nematomorpha (Nematoida, subgroup of Cycloneuralia).’
- ‘Other ecdysozoan phyla include Nematoda, Tardigrada, and Onychophora; this classification thus removes onychophorans from the Arthropoda and makes them an outgroup.’
- ‘Furthermore they have several plesiomorphic characters, such as a myoepitheal pharyngeal bulb, comparable to the other Cycloneuralia, especially the Nematoda and Gastrotricha.’
- ‘Invertebrates were identified to genus or species, with the exception of Nematoda, Turbellaria, and terrestrial invertebrates, which were typically identified only to Family or Order.’
Modern Latin (plural), from Greek nēma, nēmat- thread.