Saurida

Russell, Barry C., 2015, A new species of Saurida (Pisces: Synodontidae) from the Mascarene Plateau, Western Indian Ocean, Zootaxa 3947 (3), pp. 440-446 : 445

Key to species of Saurida of the Western Indian Ocean

1a. Longest ray of dorsal fin 2–3 times as long as last ray; scale in axil of pectoral fin short and broad; all fins with series of dark bars or spots.......................................................................................... 2

1b Longest ray of dorsal fin>3 times as long as last ray; scale in pectoral-fin axil long and pointed; fins (except first dorsal and caudal rays in some species) without dark bars or spots........................................................ 3

2a Pectoral fin short, tip just reaching insertion of pelvic fins, reaches a vertical through fourth predorsal scale only; pectoral fins usually with 12 (rarely 11 or 13) rays; vomer toothless; inner palatine teeth in 2 distinct rows; dark pigment always present on gill filaments and upper half of peritoneal cavity.................................... S. nebulosa (Indo-West Pacific)

2b Pectoral fin long, tip extending beyond insertion of pelvic fins, reaches a vertical through second or third predorsal scales; pectoral fins with 13 (rarely 12 or 14) rays; small patch of teeth on vomer; inner palatine teeth in about 3 poorly-defined rows; gill filaments often without pigment; peritoneal pigment usually restricted to narrow band over the kidneys............................................................................................... S. gracilis (Indo-West Pacific)

3a Pectoral fin very long, extending beyond line between origin of dorsal fin and origin of pelvic fins, its length 18–24% of SL....................................................................... S. longimanus (Western Indian Ocean)

3b Pectoral fin short or moderately long, not reaching to or extending a little beyond line between origin of dorsal fin and origin of pelvic fins, its length <18% of SL........................................................................ 4

4a Lateral line scales 50–53; pectoral fins not or only just reaching to base of pelvic fins; caudal peduncle, depressed, slightly wider than deep; middle rays of pelvic fins dusky.................................. S. tumbil (Western Indian Ocean)

4b Lateral line scales 53–55; pectoral fins reaching beyond base of pelvic fins; caudal peduncle compressed, deeper than wide; pelvic fins unpigmented................................................................................ 5

5a Outer palatines with 3 rows of teeth anteriorly; diameter of eye 20–25% of head length; body pigment extending 4–5 scale rows below lateral line; stomach dark pigmented anteriorly, intestine black......................... S. golanii (Red Sea)

5b Outer palatines with 2 rows of teeth anteriorly; diameter of eye 15–18% of head length; body pigment extending only 1–2 scale rows below lateral line; stomach and intestine pale whitish...... S. tweddlei n. sp. (Mascarene Plateau, Indian Ocean)