N.B.: considered a senior synonym of Utopiellum Strand, 1901b: 31 [urn:lsid:nmbe.ch:spidergen:05241] (type Erigone mirabilis L. Koch, 1879 = Hilaira herniosa (Thorell, 1875)) by Holm, 1945b: 28, of Arctilaira Chamberlin, 1921c: 39 [urn:lsid:nmbe.ch:spidergen:05242] (type A. bellans Chamberlin, 1921 = Hilaira vexatrix (O. Pickard-Cambridge, 1877)) by Holm, 1960b: 119, and of Soudinus Crosby & Bishop, 1936b: 59 [urn:lsid:nmbe.ch:spidergen:05240] (type Gongylidium canaliculatum Emerton, 1915) by Marusik et al., 1993a: 68; not a junior synonym of Leptothrix Menge, 1869 (Merrett, Locket & Millidge, 1985: 397, contra Millidge, 1977); not a senior synonym of Oreoneta Chyzer & Kulczyński, 1894 (Saaristo & Marusik, 2004a: 208, not accepted by Breitling, 2021: 21).