Key to males of Australian species of Goniagnathus.

1. Aedeagal shaft bearing prominent lateral processes over most of apical half (Figures 38–39, 43–44).....2

– Aedeagal shaft lacking processes, except short denticulations subapically in some species......................3

2. Pygofer (Figure 35) broadly rounded, lacking processes; aedeagus, in posterior view (Figure 39), broadly lanceolate with strong lateral serrations; brachypterous in known specimens.............................................. ............................................................................................................... Goniagnathus crocodontis sp.nov.

– Pygofer (Figure 40) apically obliquely truncate, with short triangular dorsal tooth and ventrally prominent posteriorly; aedeagus, in posterior view (Figure 44), narrow with long lateral teeth; macropterous in known specimens ...................................................................................... Goniagnathus pectinatus sp.nov.

3. Aedeagal shaft (Figures 16, 22) long and fine elongate with preapical process or serrations on anterior margin; Pygofer ventrally produced (Figure 13) or rounded (Figure 19); macropterous in known specimens.............................................................................................................................................................4

– Aedeagal shaft (Figure 32) short, thick, lacking processes preapically; pygofer (Figure 29) shallowly emarginate ventrally to form two short ventral processes; brachypterous in known specimens................... ................................................................................................................. Goniagnathus venenensis sp.nov.

4. Pygofer with dorsal tooth, posteroventrally rounded, not prominent (Figure 19); aedeagus with row of short anterior serrations preapically on each side (Figures 22–24) .......... Goniagnathus centralis (Evans)

– Pygofer apically rounded without dorsal tooth, prominently produced posteroventrally (Figure 13); aedeagus apically sagittate with anterior preapical tooth on each side (Figure 16) ............................................... .................................................................................................................... Goniagnathus osmelaki sp.nov.