Staurozoa is a class of Medusozoa (or jellyfish). It has one extant order: Stauromedusae (stalked jellyfishes) with a total of 50 known species. A fossil group called Conulariida has been proposed as a second order, although this is highly speculative. This extinct order is largely unknown and described as a possibly cnidarian clade of marine life with shell-like structures. Staurozoans are small animals (1–4 cm or 0.4–1.6 in) that live in marine environments, usually attached to seaweeds, rocks, or gravel. They have a large antitropical distribution, a majority found in boreal or polar, near-shore, and shallow waters. Few staurozoans are found in warmer tropical and subtropical water environments of the Atlantic, Indian, and Pacific Ocean basins, but most are known from the Northern Hemisphere. Over the years the number of discovered species has increased, with an estimated 50 species currently recognized. Information on Staurozoa is sparse, and it is one of the least studied groups within Cnidaria.

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