The conodont fauna extracted from a boulder in the Lorentz River (southern Irian Jaya) is described. Arguments are put forward that the elements of Distomodus dubius (Rhodes, 1953) sensu Jeppsson, 1972 are part of the apparatus of species of Coryssognathus Link & Druce, 1972, a genus that ontogenetically acquires an apparatus of multidenticulate elements on account of the phenomenon that one coniform element of each of the several (curvature-transition ?) series successively incorporates its - to that time independently growing - coniform neighbours within its lamellae. Attention is called to the fact that probably also the apparatus of Distomodus kentuckyensis Branson & Branson, 1947 - as described by Cooper (1975) had a similar ontogeny and that it needs to be investigated whether other species assigned to Distomodus are congeneric.