Two new spider genera, Rhinocosmetus gen. nov. and Rhinoliparus gen. nov. belonging to the family Theridiidae are described. They share the presence in males of a clypeus protrusion of which the frontal top is provided with specialized bent setae, with swollen and recurved tip, we call cotyledonoid setae. In the males of Rhinocosmetus gen. nov., the clypeal protrusion is very long and finger shaped. Other characteristics are the position of the cymbium on the prolateral side of the bulbus and the distal prong of the theridiid tegular apophysis curved prolaterad. Females often have copulatory ducts with very wide stretches and two pairs of spermathecae. Rhinocosmetus gen. nov. contains seventeen species of which fourteen are here described as new. The newly described species are: Rhinocosmetus argentatus sp. nov. (♂♀) the type species of the genus, Rhinocosmetus atropyga sp. nov. (♂♀), Rhinocosmetus cochleatus sp. nov. (♂♀), Rhinocosmetus djojosudharmoi sp. nov. (♂), Rhinocosmetus dolichogaster sp. nov. (♀), Rhinocosmetus dolichorhinus sp. nov. (♂♀), Rhinocosmetus gretathunbergae sp. nov. (♂♀), Rhinocosmetus gunungleuser sp. nov. (♀), Rhinocosmetus lombok sp. nov. (♂), Rhinocosmetus megarhinus sp. nov. (♂♀), Rhinocosmetus nasicornis sp. nov. (♂♀), Rhinocosmetus pinocchio sp. nov. (♂), Rhinocosmetus skoliorhinus sp. nov. (♂♀) and Rhinocosmetus sumba sp. nov. (♀). Argyrodes carnicobarensis Tikader, 1977 formerly synonymized with Faiditus xiphias, is revalidated and transferred here (Rhinocosmetus carnicobarensis (Tikader, 1977) sp. rev., comb. nov.) together with Argyrodes nasutus O. Pickard- Cambridge, 1880 = Rhinocosmetus nasutus (O. Pickard-Cambridge, 1880) comb. nov. and Faiditus xiphias (Thorell, 1887) = Rhinocosmetus xiphias (Thorell, 1887) comb. nov. Males of Rhinoliparus gen. nov. have a short, thick clypeal protrusion and very long first legs, whereas the cymbium is in the usual dorsal position on the bulbus and the distal prong of the theridiid tegular apophysis is curved prolaterad. Females have entrance ducts with wide stretches. Rhinoliparus gen nov. contains nine species of which four are here described as new: Rhinoliparus nafithiamae sp. nov. (♂♀), the type species, Rhinoliparus missai sp. nov. (♂♀), Rhinoliparus platyrhinus sp. nov. (♂) and Rhinoliparus queensland sp. nov. (♂). The following species are transferred here: Argyrodes kulczynskii (Roewer, 1942) = Rhinoliparus kulczynskii (Roewer, 1942) comb. nov., Argyrodes lanyuensis Yoshida, Tso & Severinghaus, 1998 = Rhinoliparus lanyuensis (Yoshida, Tso & Severinghaus, 1998) comb. nov., Argyrodes mertoni Strand, 1911 = Rhinoliparus mertoni (Strand, 1911) comb. nov., Argyrodes neocaledonicus Berland, 1924 = Rhinoliparus neocaledonicus (Berland, 1924) comb. nov. and Argyrodes rainbow (Roewer, 1942) = Rhinoliparus rainbowi (Roewer, 1942) comb. nov.