Amphiglena is a clade of sabellid annelids that has 12 named species from around the world. New COI and 18S sequences were combined with some available data to generate a molecular phylogeny for Amphiglena. Two new species of Amphiglena are described as a result, using an integrative approach combining molecular evidence with morphological descriptions using histology, 3D reconstructions and electron microscopy. Amphiglena seaverae n. sp is described from Florida, USA and Amphiglena joyceae n. sp. from Edithburgh, South Australia. Our analyses also reveal a previously underemphasized species complex in the Mediterranean, with up to six undescribed species. This highlights the potential diversity of these minute annelid worms yet to be named.