Nematodes phylum, one of the largest phylums in the animal kingdom, has more than 28,000 species that have been recorded, and there are still a large number of species that remain unnamed and undiscovered. Nematodes are widely distributed, whether in fresh water, seawater, land, or on land, often surpassing other animals in terms of individual number and species, and can be found in extreme environments such as Antarctica and trenches. In addition, there are many species of nematodes that are parasitic (more than 16,000 species), including many plants and pathogens of animals, including humans.
Overall image of the nematodes (image source Baidu)
Overall image of the nematodes
Microstructure of the nematode head
Nematodes tail structure
Males cross-spin microscopic structures
Nematodes and caudal structures