Key to the males of species of Rhaucus

(not including R. trilineatus)

1. DS with transverse-colored stripes on scutal grooves (see Figs. 2A, 6A and 15A in García & Kury, 2017)............... 2

- DS with reticular pattern on lateral sides of cephalothorax or extended laterally on abdomen (figs 2A and 5A)............ 4

2. Area III of the dorsal scutum with mammiliform tubercles (see Figs. 2D and 3B in García & Kury, 2017)............... 3

- Area III of the scutum with acuminate tubercles (Fig. 2B and 5B), Fe IV with two longitudinal rows of tubercles increasing in size distally (see Fig. 7E in García & Kury, 2017); dorsal process of glans spoon-shaped (see Fig. 8F in García & Kury, 2017)..................................................................................... R. quinquelineatus

3. Fe III with two ventral longitudinal rows of tubercles equal in size (see Fig. 3D in García & Kury, 2017), MS B areolate (Fig. 7B)...................................................................................... R. vulneratus

- Fe III with a row of outstanding tubercles (see Fig. 16D in García & Kury, 2017; MS B volcano-shaped (Fig. 4D)... R. florezi

4. Area III of DS with dome-shaped tubercles (see Fig. 9C and 12C in García & Kury, 2017)........................... 5

- Area III of DS with acuminate tubercles (Fig. 2B and 5B)..................................................... 6

5. Fe IV with ventral tubercles not well developed increasing in size distally (see Fig. 13E in García & Kury, 2017); Pa IV with outstanding tubercles on the apical portion; dorsal process of glans finger-shaped elongate (see Fig. 14G in García & Kury, 2017)....................................................................................... R. robustus

- Fe IV with two ventral rows of tubercles increasing in size distally (see Fig. 10E in García & Kury, 2017); Pa IV with retrolateral outstanding tubercles; dorsal process of glans finger-shaped, short (see Fig. 11G in García & Kury, 2017)....... R. serripes

6. Fe IV with two longitudinal rows of tubercles being outstanding at the distal portion of the Fe (Fig. 3E)................. 7

- Fe IV with two well developed rows of tubercles covering all length of Fe (Fig. 3G)................................ 8

7. Pattern of color with almost complete arborescent chevron, complex omega stripe and abdominal grooves with patches (Figs. 5A); dorsal process of glans spoon-shaped (Fig. 7C–D); MS B areolate (Fig. 7B).................... R. gaiterus sp. nov.

- Pattern of color formed by two lateral longitudinal patches from the prosoma to the posterior areas of the DS (Fig. 8A–B); dorsal process of glans finger-shaped (Fig. 8E–F); MS E and B volcano-shaped (Fig. 8D)........ R. marmoratus comb.nov.

8. Fe III with two ventral longitudinal rows of tubercles equal in size; VP with distal corners not laterally extended (see Fig. 8C–D in García & Damron, 2019)............................................................ R. serratus comb. nov.

- Fe III with two ventral longitudinal rows of tubercles increasing in size distally (Fig. 3F); VP with distal corners laterally extended (Fig. 4A, B and F)............................................................................. 9

9. Color pattern with patches on the prosoma, extended toward the lateral portion of the abdominal scutum, and patches on areas IV and V (Fig. 2A–B); dorsal process of glans spoon-shaped, wide distally (Fig. 4A)................... R. artifex sp. nov.

- Color pattern with patches on lateral sides of prosoma, extended internally on area I, surrounding the paramedian tubercles on this area (see Fig. 2A–B in García & Ahumada, 2018); dorsal process of glans spoon-shaped, narrow distally (see Fig. 7C in García & Kury, 2018)...................................................................... R. papilionaceus