Key to the adult species of the genus Pareques .

1a. Dark bar on upper head between eyes absent; broad oblique dark bar from dorsal-fin origin to anal fin absent............ 2

1b. Dark bar on upper head between eyes present; broad oblique dark bar from dorsal fin origin to anal fin present.............................................................................................. P. iwamotoi (Atlantic)

2a. 35–45 dorsal-fin soft rays.............................................................................. 3

2b. 32–33 dorsal-fin soft rays............................................................... P. perissa (Pacific)

3a. First dorsal fin without yellow rear edge; 7–8 anal-fin rays.................................................... 4

3b. First dorsal fin with yellow rear edge; 6–7 anal-fin rays.................................... P. fuscovittatus (Pacific) 4a. Chin with 5 pores..................................................................................... 5

4b. Chin with 6 pores.................................................................... P. umbrosus (Atlantic)

5a. 50–59 scales at lateral line.............................................................................. 6

5b. 44–49 scales at lateral line........................................................... P. acuminatus (Atlantic)

6a. 35–41 dorsal-fin soft rays.............................................................................. 7

6b. 42–45 dorsal-fin soft rays................................................................. P. sp. A (Pacific)

7a. 12–15 gill rakers on first arch, stripes on head and body....................................... P. lineatus (Atlantic)

7b. 15–17 gill rakers on first arch, stripes only on body or absent.................................................. 8

8a. Four thin black horizontal stripes on body; 35–38 dorsal-fin soft rays............................. P. lanfeari (Pacific)

8b. Charcoal grey, no stripes on body; 40–41 dorsal-fin soft rays..................................... P. viola (Pacific)