Brasilocaenis, Puthz, 1975

Keys to Brasilocaenis View in CoL nymphs from Brazil

1 Dorsal surface of the operculate gill smooth................................................................ 2 Dorsal surface of the operculate gill covered with short robust spines or microspines ( Fig. 6C View FIGURE 6 )........................ 3

2 Posterior tarsal claw with about 30 denticles; long and sharp posterolateral projections on abdominal segments V–VIII (see Figs. 3G View FIGURE 3 and 2C View FIGURE 2 in Nascimento et al. 2021)............................................. Brasilocaenis atawallpa Posterior tarsal claw with about 20 denticles; short posterolateral projections on abdominal segments V–VIII (see Figs. 33 and 16 in Lima et al. 2016)......................................................................... B. elidioi

3 Dorsal surface of the operculate gill covered with short robust spines (see Figs. 10B and 10D in Lima et al. 2019; triangular meso and metacoxal processes........................................................................... 4 Dorsal surface of the operculate gill covered with microspines ( Fig. 6C View FIGURE 6 ); semicircular meso and metacoxal processes ( Fig. 8B–C View FIGURE 8 )..................................................................................... B. mendesi View in CoL

4 Long meso and metacoxal processes with pointed apex (see Fig. 9D in Malzacher, 1986); anterolateral margin of the pronotum rounded or pointed.................................................................................... 5 Short meso and metacoxal processes with rounded apex (see Fig. 9E in Malzacher, 1986); rounded anterolateral margin of the pronotum (see Fig 8B View FIGURE 8 in Malzacher, 1986)........................................................... B. puthzi View in CoL

5 Anterolateral margin of the pronotum rounded (see Fig 13B in Lima et al. 2019)............................ B. renata Anterolateral View in CoL margin of the pronotum pointed (see Fig 8A View FIGURE 8 in Malzacher, 1986)............................. B. irmleri View in CoL