Key to Lutosa species based on females

1. Subgenital plate predominantly triangular, never emarginated.................................................. 2

- Subgenital plate rectangular wider than long, with emarginate posterior border, in a sinuous notch and with rounded lateral borders (Fig. 1F)........................................................................ L. morsellii n. sp.

2. Lateral lobe of the pronotum and the lateral surface of the thorax and abdomen mostly ocher or yellow in the lower half. Subgenital plate triangular................................................................................. 3

- Body without yellowish coloration on the lateral surface (Fig. 9A). Subgenital plate rectangular, three times longer than wide, and with a rounded posterior border (Fig. 9D)..................................................... L. goeldiana

3. Fore tibia with tympana................................................................................ 4

- Fore tibia without tympana (Fig. 10C)........................................................... L. paranensis

4. Lower posterior corner of the lateral lobes of the pronotum not curving inward. Subgenital plate triangular, with the posterior border mostly rounded. Posterior border of the last sternite generally straight, not conspicuously covering the base of the subgenital plate......................................................................................... 5

- Lower posterior corner of the lateral lobes of the pronotum moderately curving inward (Fig. 4A). Subgenital plate triangular, with the apex angulated (Fig. 4D). Posterior border of the last sternite covering the base of the subgenital plate and with a shallow notch in the center.................................................................. L. quaresmai n. sp.

5. Epiproct triangular or semicircular, apex of subgenital plate rounded............................................. 6

- Epiproct pentagonal (Fig. 5D), apex of subgenital plate truncate (Fig. 5F)............................... L. marginalis

6. Abdominal sternites without sclerotized modifications........................................................ 7

- Sixth abdominal sternites with a black sclerotized thickening in the central region of the posterior border; seventh sternites with a pair of parallel grooves in distal third......................................................... L. brasiliensis

7. Central division of the tenth tergite narrow, progressively widening from the anterior margin towards the base of the cerci. Epiproct semicircle-shaped, mostly covered at the base over the lateral edges, by the last tergite....................... 8

- Central division of the tenth tergite (wider than the previous case), with similar width from the anterior margin to the base of the cerci. Epiproct rectangular, with the posterior border straight, and not covered at the base by the lateral plates of the last abdominal segment............................................................................. L. imitata

8. Tympana ovoid and conspicuous. Subgenital plate almost as long as wide, ovipositor progressively curving upwards................................................................................................. L. normalis

- Outer tympanum, smaller than the inner one. Subgenital plate two times wider than long, ovipositor curving rapidly upwards........................................................................................... L. anomala