Identification key to Cerozodus species (males)

1. Postpedicel discoidal or rounded (Figs 2A–B, 6A–B, 8A–B); stylus about three times the postpedicel length; lobe of stylus comprising approximately 1/3 to ¼ the length of the second article of stylus, short and pronounced ventrally............. 2

1’. Postpedicel conical (Figs 14A–B, 18A–B); stylus about two times the postpedicel length; lobe of stylus approximately half the length of the second article of stylus, long and less pronounced ventrally......................................... 3

2. Hypandrium with tongue-like projection at mid-posterior margin bifid (Fig. 3D); gonocoxite lacking a very short conic projection laterally, sub-apically (Fig. 4B–C); gonocoxite in lateral view without indentation ventrally, sub-apically (Fig. 4D– E) and strongly inwardly curved apically (Fig. 4B–C)............................................................................................. Cerozodus brachylobus Vieira, Rafael & Limeira-de-Oliveira, 2013 (Maranhão) .

2’. Hypandrium with tongue-like projection at mid-posterior margin rounded, not bifid (Fig. 9D); gonocoxite with a very short conic projection laterally, sub-apically (Fig. 10B–C); gonocoxite in lateral view with a U-shaped indentation ventrally, subapically (Fig. 10D–E) and slightly inwardly curved apically (Fig. 10B–C)............................................................ Cerozodus nodicornis (Wiedemann, 1828) (Mato Grosso, Mato Grosso do Sul, Goiás and São Paulo).

3. External margin of epandrial arms abruptly inwardly curved distally, forming a slight concavity sub-apically (Figs 15B–C, 15G– H); hypandrium with tongue-like projection at posterior margin bifid (Fig. 15D); gonocoxite with a very short conic projection on external margin sub-apically (Fig. 16B–C); subepandrial sclerite flat, without a pair of small vesicle-like protuberances ventrally (Fig. 16H–I)........................................ Cerozodus ayalai sp. nov. (Maranhão and Tocantins).

3’. External margin of epandrial arms smoothly inwardly curved distally (Figs 19B–C, 19G–H); hypandrium with tongue-like projection at posterior margin rounded, not bifid (Fig. 19D); gonocoxite with a rounded indentation sub-apically connecting internal and external margins (Fig. 20B–C); subepandrial sclerite with a pair of small vesicle-like protuberances ventrally (Fig. 20H–I)...................................... Cerozodus platylobus sp. nov. (Mato Grosso and Mato Grosso do Sul).