Amborotubus clarkei, new genus and species from a lowland transitional forest in the Department of Santa Cruz de la Sierra, Bolivia, is described and illustrated based on two female specimens. It is placed into the monotypic Amborotubini new tribe based on the following characters: clypeus bilobed, epipharynx with two anterior setose lobes visible in dorsal view, antennal fossa contiguous with subclypeal area and anterior portion of labrum excavated, mentum platelike and concealing labium and maxilla, pronotal carina asetose, hypomeron with glabrous ocular rests, mesoventrite visible in ventral view, femora and tibiae flattened, tarsal pads transverse and poorly developed, ovipositor with apical styli. The relationship of Amborotubus to other nitidulines is unknown. It is similar in appearance to members of the Australian tribe Cychramptodini, but differs in many morphological details.