Key to Brazilian genera of Plecoptera based on last­instar nymphs 1 Thoracic gills present (Fig. 1), sometimes subanal lobe gill also present; mandible with apical teeth sharp, molar region inconspicuous (Fig. 3); maxillae with setal rows below lacinial teeth (Fig. 5); labium with poorly developed glossae and well developed round paraglossae (Fig. 7); pronotum ellipsoid with posterior margin with median concavity (Fig. 9); paraproct small and quadrangular, not visible in ventral view (Fig. 11) ......................................................................... Perlidae … 2 1' Thoracic gills absent, anal gill rosette always present (Fig. 2); mandibles with apical teeth blunt, molar region well developed (Fig. 4); maxillae with rows of setae on apex of lacinia, covering partially or completely lacinial teeth (Fig. 6); labium with glossa and paraglossa well developed, subequal and digitiform (Fig. 8); pronotum subquadrangular, posterior margin without median concavity (Fig. 10a) or with large triangular anterolateral projections (Fig. 10b); paraproct large and triangular, visible on ventral view (Fig. 12). ............................. Gripopterygidae … 5 FIGURES 1­ 3 ­5­7­9­11. Perlidae. 2­4­6­8­10 a­10b­12. Gripopterygidae. 1. Anacroneuria sp., ventral view showing thoracic gills (tg).; 2. Gripopteryx sp., dorsal view showing the anal gill rosette (gr).; 3. Kempnyia sp., right mandible ventral view; 4. Gripopteryx sp., right mandible ventral view; 5. Kempnyia sp, right maxilla ventral view; 6. Guaranyperla sp., right maxilla ventral view; 7. Kempnyia sp., labium; 8. Gripopteryx sp., labium; 9. Anacroneuria, head and pronotum (dorsal view); 10a. Paragripopteryx sp., head and pronotum (dorsal view); 10b. Guaraniperla sp., head and pronotum (dorsal view); 11. Macrogynoplax sp., end of abdomen (ventral view) showing paraprocta (p); 12. Paragripopteryx sp.., end of abdomen (ventral view showing paraprocta (p). FIGURES 13­15­17­19­21 Macrogynoplax, 14­16­18­20­22­ Anacroneuria. 13 and 14. left mandible, ventral view; 15 and 16. left maxilla, ventral view; 17 and 18. labium; 19 and 20. head and pronotum; 21 and 22. left foreleg, lateral view. 2 (1) Mandibular basal teeth acute and prominent (Fig. 13); maxillae with inner margin concave (Fig. 15); maxillary and labial palpi slender, 2nd and 3rd segments of maxillary palpus at least 5 times as long as wide, 2nd segment of labial palpus at least 7 times as long as wide. (Figs 15, 17); posterior margin of pronotum with lateral expansion (Fig. 19); foreleg raptorial (Fig. 21) .............................. Macrogynoplax 2’ Mandibular basal teeth blunt (Fig. 14); maxillae with inner margin not concave (Fig. 16); maxillary and labial palpi not so slender as in Macrogynoplax, 2nd and 3rd segments of maxillary palpus less than 5 times as long as wide and 2nd segment of labial palpus less than 7 times as long as wide (Figs 16, 18); posterior margin of pronotum without lateral expansion (Fig. 20); foreleg not raptorial (Fig. 22) ..... 3 3 (2’) Two ocelli present; post­frontal line with median portion not curving anteriorly between ocelli (Fig. 23); interocellar distance 1/3 or less of distance from each ocellus to adjacent eye (Fig. 23); maxillae with dorsal patch of small setae adjacent to inner margin (Fig. 25); fore femora usually with transverse row of well developed setae (Fig. 27); supra­coxal gills SC2 and SC3 absent (Fig. 29); pleural gill III composed by three rami basally, inserted ventrally, and very apparent in ventral view; subanal lobe gills absent (Fig. 31) ............................... Anacroneuria 3’ Two or three ocelli present; post­frontal line with median portion curving anteriorly in between paired ocelli (Fig. 24); interocellar distance 2/3 of distance from each ocellus to adjacent eye (Fig. 24); maxillae without dorsal patch of small setae adjacent to inner margin (Fig. 26); fore femora without transverse row of well developed setae (Fig. 28); supra­coxal gills SC1, SC2 and SC3 present (Fig. 30); pleural gill III composed by single ramus basally, inserted laterally, and not very apparent in ventral view; subanal lobe gills present or absent (Fig. 32) ............... 4 4 (3’) Femur with ventral sulcus extending from apex to near the base (Fig. 33) ............. ................................................................................................ Enderleina (see text) 4’ Femur with ventral sulcus restricted to apical 2/3 (Fig. 34) ................... Kempnyia 5 (1’) Pronotum with large triangular anterolateral projection, flanking head (Fig. 10b); dorsum with vesicular setae (Fig. 35); abdominal tergum X with elongate median posterior projection (Fig. 36) ............................................................ Guaranyperla 5’ Pronotum without anterolateral projection (Fig. 10a); dorsum without vesicular setae; abdominal tergum X without posterior median projection (Fig. 37), if median projection present, it is spine­like and curved ventrally (Fig. 38) ........... 6 6 (5’) Thoracic and abdominal terga with spines, sometimes thoracic spines small (Figs 38, 39) Gripopteryx 6’ Thoracic and abdominal terga without spines (Fig. 40) ........................................ 7 7 (6’) Mandible with setae present on molar region and/or posterad (Fig. 41); femora without ventral spine (Fig. 43) ..................................................... Paragripopteryx 7’ Mandibles glabrous (Fig. 42); femora with ventral spine (Fig. 44) .......... Tupiperla

Published as part of Olifiers, Martina H., Dorvillé, Luís F. M., Nessimian, Jorge L. & Hamada, Neusa, 2004, A key to Brazilian genera of Plecoptera (Insecta) based on nymphs, pp. 1-15 in Zootaxa 651 on pages 4-7, DOI: 10.5281/zenodo.158008