Brasilocaenis, Puthz, 1975

Oliveira, Laura Almeida De, Corrêa, Amanda Da Silva, Lima, Lucas R. C. & Couceiro, Sheyla R. M., 2025, Life stages of Brasilocaenis mendesi Malzacher, 1998 (Ephemeroptera: Caenidae) with redescription of male imago, Zootaxa 5692 (3), pp. 506-518 : 517

Keys to Brasilocaenis 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 )........................ 3

2 Posterior tarsal claw with about 30 denticles; long and sharp posterolateral projections on abdominal segments V–VIII (see Figs. 3G and 2C 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 ); semicircular meso and metacoxal processes ( Fig. 8B–C )..................................................................................... B. mendesi

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 in Malzacher, 1986)........................................................... B. puthzi

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

Figures

FIGURE 2. Male imago, Brasilocaenis mendesi Malzacher. A, habitus in dorsal view; B, habitus in lateral view; C, habitus in ventral view; D, details of pro- and mesosternum (ventral view); E, details of thorax (lateral view). (Scale = 0.5 mm).

FIGURE 3. Male genitalia, Brasilocaenis mendesi Malzacher.A–D, variations of styliger plate (dashed line indicates posterior margin). (Scale = 0.1 mm).

FIGURE 6. Nymph, Brasilocaenis mendesi Malzacher. A, habitus in dorsal view; B, habitus in ventral view; C, opercular gill (dorsal view; D, opercular gill (detail of the central row of microtrichia); E, enlarged detail of the central row of microtrichia; F, gill. (Scale: Figs. 6A–B = 1 mm; 6C, F = 0.5 mm; 6D = 20 μm; 6F = 10 μm).

FIGURE 8. Nymph, Brasilocaenis mendesi Malzacher. A, foreleg; B, middle leg; C, hind leg; D, fore tarsal claw; E, middle tarsal claw; F, hind tarsal claw. (Scale: Figs. 8A–C = 0.5 mm; D–F = 0.05 mm).