Pilumnoidea is a superfamily of crabs, whose members were previously included in the Xanthoidea. The three families are unified by the free articulation of all the segments of the male crab's abdomen and by the form of the gonopods. The earliest fossils assigned to this group are of Eocene age. Classification Pilumnidae is by far the largest of the three families, with 73 of the 78 genera: Pilumnidae Samouelle, 1819 Subfamily Calmaniinae Števčić, 1991 Calmania Laurie, 1906 Subfamily Pilumninae Samouelle, 1819 Actumnus Dana, 1851 Aniptumnus Ng, 2002 Bathypilumnus Ng & L. W. H. Tan, 1984 Benthopanope Davie, 1989 Budapanopeus † Müller & Collins, 1991 Cryptopilumnus Hsueh, Huang & Ng, 2009 Danielum Vázquez-Bader & Gracia, 1995 Eohalimede † Blow & Manning, 1996 Eopilumnus † Beschin et al., 2002 Eumorphactaea † Bittner, 1875 Eurycarcinus A. Milne-Edwards, 1867 Galenopsis † A. Milne-Edwards, 1865 Glabropilumnus Balss, 1932 Gorgonariana Galil & Takeda, 1988 Heteropanope Stimpson, 1858 Heteropilumnus De Man, 1895 Latopilumnus Türkay & Schuhmacher, 1985 Lentilumnus Galil & Takeda, 1988 Lobogalenopsis † Müller & Collins, 1991 Lobopilumnus A. Milne-Edwards, 1880 Lophopilumnus Miers, 1886 Nanopilumnus Takeda, 1974 Neoactumnus T. Sakai, 1965 Parapleurophrycoides Nobili, 1906 Pilumnopeus A. Milne-Edwards, 1867 Pilumnus Leach, 1816 Priapipilumnus Davie, 1989 Pseudactumnus Balss, 1933 Serenepilumnus Türkay & Schuhmacher, 1985 Serenolumnus Galil & Takeda, 1988 Takedana Davie, 1989 Viaderiana Ward, 1942 Xestopilumnus Ng & Dai, 1997 Xlumnus Galil & Takeda, 1988 Subfamily Eumedoninae Dana, 1853 Ceratocarcinus Adams & White in White, 1847 Echinoecus Rathbun, 1894 Eumedonus H. Milne Edwards, 1837 Gonatonotus Adams & White, in White, 1847 Hapalonotus Rathbun, 1897 Harrovia Adams & White, 1849 Permanotus D. G. B. Chia & Ng, 1998 Rhabdonotus Milne-Edwards, 1879 Santeella † Blow & Manning, 1996 Tauropus D. G. B. Chia & Ng, 1998 Tiaramedon D. G. B. Chia & Ng, 1998 Viacarcinus † Blow & Manning, 1996 Zebrida White, 1847 Zebridonus D. G. B. Chia, Ng & Castro, 1995 Subfamily Rhizopinae Stimpson, 1858 Caecopilumnus Borradaile, 1902 Camptoplax Miers, 1884 Ceratoplax Stimpson, 1858 Cryptocoeloma Miers, 1884 Cryptolutea Ward, 1936 Itampolus Serène & Peyrot-Clausade, 1977 Lophoplax Tesch, 1918 Luteocarcinus Ng, 1990 Mertonia Laurie, 1906 Paranotonyx Nobili, 1905 Paraselwynia Tesch, 1918 Peleianus Serène, 1971 Pronotonyx Ward, 1936 Rhizopa Stimpson, 1858 Pseudocryptocoeloma Ward, 1936 Pseudolitochira Ward, 1942 Rhizopoides Ng, 1987 Ser Rathbun, 1931 Typhlocarcinops Rathbun, 1909 Typhlocarcinus Stimpson, 1858 Zehntneria Takeda, 1972 Subfamily Xenopthalmodinae Števčić, 2005 Arges † De Haan, 1835 Xenopthalmodes Richters, 1880 Galenidae Alcock, 1898 Dentoxanthus Stephensen, 1946 Galene