Emarginulinae

The subfamily Emarginulinae, common name keyhole limpets and slit limpets, is a taxonomic subfamily of limpet-like sea snails, marine gastropod molluscs in the family Fissurellidae, the keyhole limpets and slit limpets.
The subfamily consists of the following tribes:

Tribe Emarginulini Children, 1834 - synonyms: Rimulidae, Anton, 1838; Zeidoridae Naef, 1913; Hemitominae Kuroda, Habe & Oyama, 1971; Clypidinidae Golikov & Starobogatov, 1989
Tribe Diodorini Odhner, 1932: this tribe has been raised to the rank of subfamily Diodorinae Odhner, 1932
Tribe Fissurellideini Pilsbry, 1890
Tribe Scutini Christiaens, 1973

Of the subfamilies in Fissurellidae, the subfamily Emarginulinae is the oldest: its earliest known species date back to the Mesozoic.
The various tribes belong to this subfamily because of the unifying features in their radula. Several tribes were formerlysynonym of subfamilies, because of the differences in their shell. The Emargulini have a caplike shell with a slit in the margin but without an apical opening. The Scutini have a flat shield-shaped shell with a vague indentation at the back. The other tribes have a caplike shell with a round, oval or triangular apical opening.
The species of this subfamily can be found attached to rocks or coral. They are Herbivores.

Genera

Agariste Monterosato, 1892Altrix Palmer, 1942Arginula Palmer, 1937Buchanania Lesson, 1831Clathrosepta McLean & Geiger, 1998Clypidina Gray, 1847Emarginella Pilsbry, 1891Emarginula Lamarck, 1801

† Entomella Cossmann, 1888 Fissurisepta Seguenza, 1863Laeviemarginula Habe, 1953Laevinesta Pilsbry & McGinty, 1952Manganesepta McLean & Geiger, 1998Montfortula Iredale, 1915
† Palaeoloxotoma Hansen, 201 Parmaphorella Strebel, 1907Pupillaea Gray, 1835Rixa Iredale, 1924Scelidotoma McLean, 1966Scutus Montfort, 1810Stromboli Berry, 1954Tugali Gray, 1843Tugalina Habe, 1953Vacerrena Iredale, 1958

;Taxa inquirenda:Clypidella Swainson, 1840Rimulanax Iredale, 1924

Synonyms

Aviscutum Iredale, 1940synonym of Scutus Montfort, 1810Entomella Cotton, 1945synonym of Emarginula Lamarck, 1801

† Loxotoma P. Fischer, 1885 synonym of † Palaeoloxotoma Hansen, 2019 Nannoscutum Iredale, 1937synonym of Scutus Montfort, 1810Notomella Cotton, 1957synonym of Emarginula Lamarck, 1801Parmophoridea Wenz, 1938synonym of Parmaphorella Strebel, 1907 Parmophorus Blainville, 1817synonym of Scutus Montfort, 1810 Plagiorhytis P. Fischer, 1885synonym of Montfortula Iredale, 1915 Rimularia Bronn, 1838synonym of Rimula Defrance, 1827 Scutum P. Fischer, 1885synonym of Scutus Montfort, 1810 Semperia Crosse, 1867synonym of Emarginula Lamarck, 1801Subzeidora Iredale, 1924synonym of Emarginula Iredale, 1924 represented as Emarginula Lamarck, 1801Tugalia Gray, 1857synonym of Tugali Gray, 1843Vacerra Iredale, 1924synonym of Vacerrena Iredale, 1958 Variegemarginula McLean, 2011synonym of Montfortula Iredale, 1915