Key to the species of Macrodactylus from Bolivia

1 Body length greater than 9 mm .......................................................................... 2

- Body length less than 9 mm ............................................................................. 7

2 Antennal club black, length equal to length of antennal stalk. Vestiture does not completely obscure dorsal surface. Length 14 mm (Figs. 1–2), male genitalia (Figs. 7–9)................................... .. M. megaphyllus Arce-Pérez & Morón

- Antennal club yellow or black, length ¾ length of antennal stalk. Dorsally glabrous or with vestiture that does not completely obscure dorsal surface.................................................................................. 3

3 Dorsally aeneus-green, glabrous. Elytra striated, greenish yellow. Clypeus, antennae, legs, and pygidium yellowish red. Length 12 mm ............................................................................. M. cupreus Blanchard

- Dorsally yellowish red or intense green, glabrous or vestiture in wide rows........................................ 4

4 Males dorsally glabrous or only with vestiture on scutellum.................................................... 5

- Males dorsally with vestiture in wide rows................................................................. 6

5 Males with pronotum intense red; with sparse, yellow setae on lateral margins; scutellum with yellowish-gray setae. Elytra intense dark green, with yellowish-green and red shine; with long and short setae intermixed. Female with elytra reddish yellow; with setae on disc; pygidium prominent, red. Length 11–12 mm .............................. M. disparilis Moser

- Males dorsally glabrous; pronotum black; elytra yellowish red, with inner suture dark, dark shadows on disc (Figs 3–4). Female with elytra darkened, basal third yellowish red; pygidium subtriangular, short, weakly convex. Length 12.5 mm. Male and female genitalia (Figs. 10–13)............................................. M. yunganus Arce-Pérez & Morón

6 Head, pronotum, and inner half of elytra nearly black; with dense, white vestiture. Pronotum with three wide rows of setae, elytra with wide band along inner half. Length 12–13 mm. Male and female genitalia (Figs. 14–17)......... M. nobilis Frey

- Head and pronotum dark green; elytra yellowish red with green shine; clypeus, legs, and pygidium yellowish red. Males without wide rows of setae on pronotum. Length 9–10 mm ........................................... M. zischkai Frey

7 Dorsal surface completely covered with yellow, short setae that obscure surface (Figs. 20–21). Male and female genitalia (Figs. 26–29)................................................................................ M. gracilis Moser

- Dorsal surface with sparse setae that exposes surface; setae arranged in wide rows, narrow rows, or dispersed............. 8

8 Pronotum and scutellum dark red, with dense yellow setae that obscure surface. Elytra reddish yellow; with two yellow, wide rows. Pygidium with abundant setae. Length 9 mm ........................................ M. signatipennis Moser

- Pronotum and scutellum reddish yellow or dark red with sparse setae, surface visible. Elytral setae arranged in narrow rows. Pygidium with sparse setae............................................................................. 9

9 Pronotum dark red; elytra yellowish red; dorsally with short, white setae, and surface visible. Length 8 mm (Figs. 18–19). Male and female genitalia (Figs. 22–25)................................................... M. bolivianus Moser

- Dorsally bright reddish yellow; pronotum thickly dotted and with white setae towards lateral margins; elytra black with metallic luster, transversely rugose, with few rows of setae. Length 9 mm ................................ M. aeneus Kirsch