Overview
Derocheilocarididae is a family of marine crustaceans that form part of the meiobenthos. It is the only family in the monotypic order Mystacocaridida, and the monotypic subclass Mystacocarida. These mystacocarids are less than long, and live interstitially in the intertidal zones of sandy beaches.
Taxonomy
The taxonomy of the mystacocarids is extremely conservative, since all mystacocarids look superficially alike. , the 13 described species are divided between two genera, Derocheilocaris (eight species) and Ctenocheilocharis (five species). The first mystacocarids to be found were discovered on a beach in southern New England in 1939.
Distribution
Mystacocarids occur along the coasts of South and North America, southern Africa, and the western Mediterranean. The lack of records from other parts of the world is "almost certainly" due to a lack of appropriate sampling, rather than a true absence.
Description
Mystacocarids are tiny pigmentless crustaceans, less than long, that live in the spaces between sand grains on intertidal beaches. They have a cylindrical body, with five thoracic and five abdominal segments.
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