New Scissurellidae and Anatomidae from the geographic and political Americas are described, with many long-standing misidentifications being corrected, and some comparisons to described species complementing the contribution. Sinezona kayae n. sp., previously mis-identified as the South African Sin. insignis, and Sin. hawaiiensis n. sp. without a selenizone, are described from Hawaii. Sinezona carolarum n. sp. is added to the Panamic province with a more depressed shell than the more common Sin. rimuloides (Carpenter, 1865), and a proportionally shorter selenizone. Coronadoa demisispira n. sp. from the Panamic and northeastern Pacific provinces is the third species in the genus, living sympatrically in the southern range of C. simonsae Bartsch, 1946. The new species is characterized by a shell with lower profile and a wider umbilicus. Anatoma alternatisculpta n. sp. from the Caribbean is most similar to A. proxima (Dall, 1927), but has conspicuously different sculpture on shoulder and base. Anatoma plicatazona n. sp. from the Caribbean has markedly upturned keels of the selenizone. Anatoma disciformis (Golikov & Sirenko, 1980) is reported from Alaska and illustrated for the first time by SEM. Thieleella kelseyi (Dall, 1905) is resurrected for what has previously been misidentified as the European Anatoma crispata (Fleming, 1828) in the northeastern Pacific, with a neotype designated, as the holotype is missing. Thieleella peruviana n. sp. from Peru is similar to T. kelseyi but has a taller shell and differs in the morphology of lateral tooth 5 of the radula. Thieleella bathypacifica n. sp. from the Panamic province is a deep-water species (2500 m), and known from a single specimen only. The species shows a marked angulation on teleoconch I at the spiral cord in the position of the selenizone; additionally it has a radula with marginal teeth showing a distinct posterior food groove. The bodies of two species (T. kelseyi, T. peruviana) were examined by SEM. An accessory cephalic tentacle between the anterior most epipodial tentacle and the eye stalk was encountered. The epipodial sense organ is recognized for the first time in Anatomidae, and the presence of bursicles on the gill is confirmed.