Key to species of Opeatocerata (males)
(the following species are known only from female specimens: O. cooperi and O. rubida)
1 Tergites with brown to black spots (Figs 3, 47, 64, 90, 123, 170, 185, 195, 203)................................... 2
- Tergites without spots (Figs 8, 17, 26, 33, 80, 100,107, 114, 129, 138, 152, 161).................................. 9
2 Tergites with paramedian spots occupying half or more than half of the tergites (Figs 64, 90, 170, 195, 203)............ 3
- Tergites with paramedian spots occupying less than half of the tergites (Figs 47, 123, 185).......................... 7
3 Phallus long, ending well beyond the hypandrium apex in lateral view (Figs 72, 209).............................. 6
- Phallus short, ending before or just beyond the hypandrium apex in lateral view (Figs 98, 178, 199)................... 4
4 Phallus with trilobate apex (Figs 199, 200)......................................... O. trilobata Câmara & Rafael
- Phallus with a single lobe apically (Figs 98, 178)........................................................... 5
5 Tergites with paramedian subtriangular spots in dorsal view (Fig. 93)........................ O. hadrophallus sp. nov.
- Tergites with paramedian subretangular spots in dorsal view (Fig. 173).............................. O. stubbsi Smith
6 Phallus curved down (Fig. 72). Epandrial lobe acuminate at apex (Fig. 68)....................... O. curvipenis sp. nov.
- Phallus curved up (Fig. 209). Epandrial lobe truncate at apex (Fig. 205)......................... O. zuleideae sp. nov.
7 Anterior cercus with reclinate dorsal projection in lateral view (Fig. 51). Posterior cercus without dorsal projections (Fig. 52). Subepandrial sclerite V-shaped in dorsal view (Fig. 54)............................... O. chaetohypandrialis sp. nov.
- Anterior cercus with proclinate dorsal projection in lateral view (Figs 124, 189). Posterior cercus with a dorsal triangular pro- jection (Figs 125, 190). Subepandrial sclerite U-shaped in dorsal view (Fig. 192).................................. 8
8 Tergites with paramedian suboval spots in dorsal view (Fig. 188). Epandrial lobe slightly bilobate in lateral view (Fig.189). Phallus with a subapical dorsal spine-like projection (Fig. 193)................................ O. tanimboca sp. nov.
- Tergites brown on lateral margin, without paramedian spots in dorsal view (Fig. 123). Epandrium with a single lobe in lateral view (Fig. 124). Phallus without a subapical spine-like projection (Fig. 126).............. O. melanderi Câmara & Rafael
9 Phallus without dorsal appendix (Figs 88, 121, 144)........................................................ 10
- Phallus with dorsal appendix (Figs 15, 24, 32, 40, 55, 107, 136, 159, 167)...................................... 12
10 Tergite 8 undivided (Fig. 83). Posterior cercus without dorsal projection (Fig. 78)............ O. cylindrophallus sp. nov.
- Tergite 8 divided in two plates (Fig. 4). Posterior cercus with a basal pointed dorsal projection (Figs 118, 141)......... 11
11 Subepandrial sclerite longer than bacilliform sclerite in dorsal view (Fig. 120). Posterior cercus with a dorso-median subtrian- gular projection (Fig. 118)......................................................... O. megalophallus sp. nov.
- Subepandrial sclerite shorter than bacilliform sclerite in dorsal view (Fig. 143). Posterior cercus without a dorso-median pro- jection (Fig. 141).................................................................... O. nhamunda sp. nov.
12 Phallus with a dorsal subbasal appendix (Figs 15, 136)..................................................... 13
- Phallus with a dorsal subapical appendix (Figs 24, 32, 40, 55, 107, 159, 167).................................... 14
13 Anterior cercus with dorsal pro and reclinate projections in lateral view (Figs 132). Phallus without ventral appendix (Fig. 136)..................................................................................... O. mourai sp. nov.
- Anterior cercus with dorsal proclinate projection in lateral view (Fig. 11). Phallus with subapical ventral appendix (Fig. 15)...................................................................................... O. agudeloi sp. nov.
14 Phallus with wide dorsal subapical appendix (Figs 24, 32, 40, 55)............................................. 15
- Phallus with narrow dorsal subapical appendix (Figs 107, 159, 167)........................................... 17
15 Posterior cercus pointed at apex in lateral view (Figs 20) and without dorsal projections (Fig. 21).... O. ampullaria sp. nov.
- Posterior cercus rounded at apex in lateral view (Figs 28, 36) and with a pointed dorsal projection (Figs 29, 37)........ 16
16 Anterior cercus with proclinate dorsal projection in lateral view (Fig. 46). Subepandrial sclerite longer than bacilliform sclerite in dorsal view (Fig. 39).............................................................. O. brasiliensis sp. nov.
- Anterior cercus with reclinate dorsal projection in lateral view (Fig. 28). Subepandrial sclerite shorter than bacilliform sclerite in dorsal view (Fig. 31)................................................................... O. bare sp. nov.
17 Posterior cercus with a basal pointed and a median subtriangular projections (Fig. 104).................. O. lopesi Smith
- Posterior cercus without dorsal projections (Figs 156, 164).................................................. 18
18 Phallus with lateral spines (Fig. 168). Epandrial lobe with rounded apex in lateral view (Fig. 163).... O. spinipenis sp. nov.
- Phallus without lateral spines (Fig. 159). Epandrial lobe with truncated apex in lateral view (Fig. 155).... O. smithi sp. nov.