†FAMILY POECILASMATIDAE ANNANDALE, 1909

Diagnosis: Monophyletic by molecular analyses; five shell plates, but often reduced in size or partly or completely lost. Epibiotic species.

Comment: The family cannot be diagnosed at present by morphological apomorphies. The family includes members of the abandoned Oxynaspitidae Gruvel, 1905 because its members are nested among the Poecilasmatidae . Yamamori & Kato (2020) showed that the former Microlepadidae Hoek, 1907 is nested within species of Octolasmis; therefore, this family is abandoned. The monophyly and relationships of most genera remain unanalysed.

†† Archoxynaspis Van Syoc & Dekelboum, 2011 (one species)

Dianajonesia Koçak & Kemal, 2008 (nine species)

Dichelaspis Darwin, 1852 (five species)

† Glyptelasma Pilsbry, 1907 (11 species)

Megalasma Hoek, 1883 (five species)

Microlepas Hoek, 1907 (two species)

Minyaspis Van Syoc & Dekelboum, 2011 (15 species)

Octolasmis Gray, 1825 (30 species)

Oxynaspis Darwin, 1852 (13 species)

Pagurolepas Stubbings, 1940 (two species)

Poecilasma Darwin, 1852 (eight species)

Rugilepas Grygier & Newman, 1991 (one species)

Scleraspis Van Syoc & Dekelboum, 2012 (one species)

Trilasmis Hinds, 1844 (one species)