INVERTEBRATE ZOOLOGY IN THREE BOOKS - BOOK 2 - G.I. Shcherbak - 1996

PHYLUM TARDIGRADA

Tardigrades are cosmopolitan microscopic animals (0.05–1.4 mm in length) inhabiting damp terrestrial biotopes, as well as freshwater and marine environments. They possess a weakly segmented body with an indistinctly demarcated HEAD and four pairs of unjointed limbs. The Digestive System is complete. Respiratory and circulatory Organs are absent. The Nervous system is of the arthropod type. They are dioecious, with direct development and growth accompanied by molting.

The phylogenetic position of tardigrades remains uncertain. They share certain characteristics with both polychaetes and Arthropods. However, Specific features of their Morphology and embryonic development indicate that they constitute an independent and highly distinctive phylum within the animal kingdom.



Last update: 13/08/2026

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