The first species of Euthriofusus from pliocene deposits of the Indo-Westpacific area was described by Cossmann (1903, p. 126, pl. 4 fig. 20) as E. inopinatus, type locality: pliocene of Karikal, India. Cossmann classed it as a Euthriofusus with some hesitation, because it did not show all the features characteristic of that genus. Recently I examined a large series of Clavilithes verbeeki (K. Martin, 1895) from lower pleistocene beds of Java, and it appeared that the young shells of that species match exactly the description and figure of E. inopinatus Cossmann. Consequently Cossmann’s name falls as a synonym²).