Sessilia is an unranked clade of barnacles, comprising the barnacles without stalks, or acorn barnacles.

They form a monophyletic group and are probably derived from stalked or goose barnacles.

[3] Sessilia is divided into two orders.

The Verrucomorpha contain two families, Verrucidae and Neoverrucidae, and the remaining 14 families are in the order Balanomorpha.

This Maxillopoda-related article is a stub.