Macrodasyida is an order of gastrotrichs. Members of this order are somewhat worm-like in form, and not more than 1 to 1.5 mm in length.
Macrodasyids are almost in entirely marine and live in the sediment in marine or brackish water, but two species have been discovered in freshwater. They can be distinguished from other gastrotrichs by the presence of two pores on either side of the pharynx, that allow excess water to be expelled during feeding. The body is dorsally flattened and there are tubular adhesive glands at both ends and on the lateral surfaces. These animals are detritivores and are hermaphrodites.