Key to nymphs of Corinnella species

1 Labrum with shallow distomedial emargination (Fig. 4a of Boldrini et al. 2013); posterior margin of terga with rounded spines (Fig. 11 of Boldrini et al. 2013); tarsal claw with seven to nine denticles, inner and outer denticles distinctly longer (Fig. 10c of Boldrini et al. 2013)............................................................................ C. thomasi

- Labrum with broad distomedial emargination (Fig. 2a); posterior margin of terga with pointed spines (Fig. 3c); tarsal claw with four denticles, one denticle distinctly longer (Fig. 3b)......................................................... 2

2 General coloration dark grey (Figs. 1c, 1d); distomedial emargination of labrum with small notches; all femora heavily washed with gray medially, apical ¼ washed with red (Figs. 1c, 3a); gills with costal and anal margins pigmented, pigmentation of tra- chea restricted to middle portion (Fig. 3c); apex of hypopharynx rounded (Fig. 2f)..................... C. lourii, sp. nov.

- General coloration brown; distomedial emargination of labrum without process; femur one with brown stripe close to ventral margin (Fig. 7 of Dominique et al. 2005); gills with costal and anal margins unpigmented, pigmentation of trachea extending from base to apex (Fig. 10 of Dominique et al. 2005); apex of hypopharynx concave (Fig. 3 of Dominique et al. 2005)................................................................................................... C. eximia