Kinorhyncha is a phylum of small marine invertebrates that are widespread in mud or sand at all depths as part of the meiobenthos. They are also called mud dragons. Modern species are 1 mm or less, but Cambrian forms could reach 4 cm.

What is the common name for Kinorhyncha?

Kinorhynchamud dragons(Also: kinorhynchs)

How many Kinorhyncha are there?

Kinorhynch, any of the approximately 150 species of microscopic marine invertebrates of the phylum Kinorhyncha, widely distributed in the world's oceans.