Bentharca xenophoricola (Kuroda, 1929) and Bentharca rubrotincta Kuroda & Habe in Habe, 1958, from Japan are re-examined. Based on comparison with the material of Bentharca asperula (Dall, 1881) and Asperarca nodulosa (Müller, 1776), the type species of Bentharca Verrill & Bush, 1898, and Asperarca Sacco, 1898, respectively, as well as on the description, pictures, and photos of Deltaodon tugelae Barnard, 1962, the type species of Deltaodon Barnard, 1962, the following new combinations are suggested: Asperarca xenophoricola (Kuroda, 1930) and Deltaodon rubrotincta (Kuroda & Habe in Habe, 1958). Asperarca xenophoricola has an elongate, inflated, thick shell, with a weakly hirsute periostracum, commarginal lamellate ridges made nodulose by the closely spaced, high radial riblets, and narrow, slightly curved hinge plate, with teeth divided into anterior and posterior sets by a narrow edentulous gap. The anterior set of this species has 7–14 long teeth; the posterior set 6–9 oblique teeth that diverge to a varying degree. This species occurs off Japan, China, and southeastern Australia at depths from 50 to 500 m. Deltaodon rubrotincta has a high, moderately inflated, thick, reddish-brown shell, with white rays and spots, commarginal lamellate ridges and high, nodules, widely spaced radial ribs, a broad, strongly curved hinge plate, with teeth divided into anterior and posterior sets by a shallow, oblique groove. The anterior set of this species forms an oval group of 4–7 long, mostly curved, boomerang-shaped teeth. The posterior set has 9–18 long, oblique teeth that diverge to a varying degree. This species occurs off Japan and China at depths from 100 to 200 m. Expanded descriptions of these species are presented.