Plesiolebias

Costa, Wilson J. E. M., 2007, Taxonomy of the plesiolebiasine killifish genera Pituna, Plesiolebias and Maratecoara (Teleostei: Cyprinodontiformes: Rivulidae), with descriptions of nine new species, Zootaxa 1410, pp. 1-41 : 20-21

Key to species of the genus Plesiolebias

1a. Pelvic-fin rays 8–9; pelvic-fins each with a long filamentous ray in males; eye yellow in males; anterior portion of flank, at least, with oblique black bars in males; red stripe of anterior portion of flanks, when present, never anteriorly reaching orbit; basal portion of dorsal fin red in males; a black spot on posterior portion of anal fin in males, most prominent in preserved specimens. ................................. 2

1b. Pelvic-fin rays 7; pelvic-fins each without filamentous rays; eye bright green in males; never oblique black bars on flanks in males; red stripe of anterior portion of flanks always anteriorly reaching orbit; basal portion of dorsal fin with transverse rows of dark red and white spots in males; never a black spot on posterior portion of anal fin in males..................................................................................................... 6

2a(1a). Body depth 23.2–25.7 % SL in males, 23.0–26.0 % SL in females; sparse bright dots on flank in males; 3 white bars on basal portion of anal fin in males...................................................................... 3

2b(1a). Body depth 28.6–32.6 % SL in males, 26.4–30.3 % SL in females; oblique rows of bright dots on flanks of males; 4–5 white bars on basal portion of anal fin in males................................................... 4

3a(2a). No red mark on anterior portion of flanks in males; no black bar on preopercle; 5–7 oblique bars on flanks in females; 24–25 scales in longitudinal series ......................................... P. fragilis , new species

3b(2a). A red stripe on anterior portion of flanks in males; a black bar on preopercle; 8–9 oblique bars on flank in females; 22–23 scales in longitudinal series ...................... P. altamira Costa & Nielsen, new species

4a(2b). Dorsal-fin origin on vertical between base of 3rd and 5th anal-fin rays; no red mark on anterodorsal portion of head in males ..................................................................................................... P. lacerdai Costa

4b(2b). Dorsal fin-origin on vertical between base of 5th and 8th anal-fin rays; red stripe on anterodorsal portion of head in males.............................................................................................................................. 5

5a(4b). Dorsal fin-origin at vertical between base of 5th and 6th anal-fin rays; 15–16 anal-fin rays; red pigmentation restricted to basal third of dorsal fin in males; small white spots on dorsal-fin base in males ..... ........................................................................................... P. filamentosus Costa & Brasil, new species

5b(4b). Dorsal fin-origin on vertical between base of 7th and 8th anal-fin rays; 17–18 anal-fin rays; red pigmentation extending to basal two thirds of dorsal fin in males; white bars on dorsal-fin base in males ....... ................................................................................................. P. xavantei (Costa, Lacerda & Tanizaki)

6a(1b). Dorsal-fin origin on vertical between base of 7th and 9th anal-fin rays; oblique rows of dark brown dots restricted to the median portion of flank, sometimes absent ................................................................. 7

6b(1b). Dorsal-fin origin on vertical through base of 5th or 6th anal-fin ray; dark brown dots and elongated spots on whole flank in females ........................................................ P. glaucopterus (Costa & Lacerda)

7a(6a). Anal-fin base with white elongate spots in males; 1 + 27–31 + 1 infraorbital neuromasts..................... ...................................................................................... P. canabravensis Costa & Nielsen, new species

7b(6a). Anal-fin base with long curved bars in males, ventral tips anteriorly directed, often converging to a point on anterior margin of fin; 1 + 16–22 + 1 infraorbital neuromasts .................... P. aruana (Lazara)