[1] Palpata includes the majority of genera and species of polychaete worms and is subdivided into the orders Aciculata and Canalipalpata.

[2] The prostomium is characterised by a pair of sensory palps which gives the subclass its name and which are lacking in the other main taxon of polychaetes, the Scolecida.

Canalipalpata is equivalent to the old taxonomic group "Sedentaria", worms that stay in one place, living in a self-made tube composed of mud or sand cemented together with mucus.

Members of Canalipalpata are worms with elongated grooved palp structures used for feeding and the order is divided into suborders Sabellida, Spionida and Terebellida.

[4] The World Register of Marine Species considers Palpata a "nomen dubium" and divides the polychaetes into three subclasses, Aciculata, Canalipalpata and Scolecida.