The males of Trypoxylon scrobiferum Richards and T. anapaike Amarante are described for the first time and their genitalia illustrated. These species are demonstrated to represent a monophyletic group, and the scrobiferum species group is established for them. The scrobiferum species group is assigned to the subgenus Trypoxylon. This represents a new subgeneric combination for T. scrobiferum Richards.
Hymenoptera; Sphecidae; Crabronidae; Crabroninae; Trypoxylini; Trypoxylon; Trypargilum; Systematics