Least concern
989 species| Photo | English | සිංහල | தமிழ் | Scientific name | IUCN | Endemic |
|---|---|---|---|---|---|---|
| Saddled Shrimpgoby | — | — | Cryptocentrus leucostictus | LC | — | |
| Saltwater Crocodile | ගැට කිඹුලා | உப்புநீர் முதலை | Crocodylus porosus | LC | — | |
| Sanderling | — | வெள்ளை உள்ளான் | Calidris alba | LC | — | |
| Sandwich Tern | — | — | Thalasseus sandvicensis | LC | — | |
| Saunders’s Tern | — | கருப்பு இறக்கைத் தண்டு சிறிய ஆலா | Sternula saundersi | LC | — | |
| Saw-scaled Viper | වැලි පොළඟා | சுருட்டை விரியன் | Echis carinatus | LC | — | |
| Scaly-Breasted Munia | — | புள்ளிச் சில்லை | Lonchura punctulata | LC | — | |
| Scarlet Adjutant | — | — | Aethriamanta brevipennis | LC | — | |
| Scarlet Basker | — | — | Urothemis signata | LC | — | |
| Scarlet Skimmer | — | — | Crocothemis servilia | LC | — | |
| Schneider’s Toad | — | — | Duttaphrynus scaber | LC | — | |
| Scissor-Tailed Fusilier | — | — | Caesio caerulaurea | LC | — | |
| Scissortail Sergeant | — | — | Abudefduf sexfasciatus | LC | — | |
| Scrawled Filefish | — | — | Aluterus scriptus | LC | — | |
| Semicircle Angelfish | — | — | Pomacanthus semicirculatus | LC | — | |
| Sharksucker | — | உருவுமீன் | Echeneis naucrates | LC | — | |
| Sharptooth Snapper | — | — | Pristipomoides typus | LC | — | |
| Shikra | — | வைரி | Tachyspiza badia | LC | — | |
| Shining Gossamerwing | — | — | Euphaea splendens | LC | Endemic | |
| Short-Finned Pilot Whale | — | குறுந்துடுப்பு வலவம் திமிங்கிலம் | Globicephala macrorhynchus | LC | — | |
| Shorthead Sabretooth Blenny | — | — | Petroscirtes breviceps | LC | — | |
| Shortnose Boxfish | — | — | Ostracion nasus | LC | — | |
| Shortnose Tripodfish | — | — | Triacanthus biaculeatus | LC | — | |
| Sicyopterus griseus | — | — | Sicyopterus griseus | LC | — | |
| Silver Moony | — | — | Monodactylus argenteus | LC | — | |
| Silver Puffer | — | — | Lagocephalus sceleratus | LC | — | |
| Similar Damsel | — | — | Pomacentrus similis | LC | — | |
| Sinuate Clubtail | — | — | Burmagomphus pyramidalis | LC | — | |
| Sirkeer Malkoha | — | கள்ளிக்குயில் | Taccocua leschenaultii | LC | — | |
| Sixband Parrotfish | — | — | Scarus frenatus | LC | — | |
| Sixbar Wrasse | — | — | Thalassoma hardwicke | LC | — | |
| Sixspot Glidergoby | — | — | Valenciennea sexguttata | LC | — | |
| Slaty-Breasted Rail | — | நீலமார்புச் சம்பங்கோழி | Lewinia striata | LC | — | |
| Slaty-Legged Crake | — | கருங்கால் கானாங்கோழி | Rallina eurizonoides | LC | — | |
| Sleepy Goby | — | — | Psammogobius biocellatus | LC | — | |
| Slender Blue Skimmer | — | — | Orthetrum luzonicum | LC | — | |
| Slender Sea Snake | — | — | Microcephalophis gracilis | LC | — | |
| Slender Skimmer | — | — | Orthetrum sabina | LC | — | |
| Slender-Billed Gull | — | — | Chroicocephalus genei | LC | — | |
| Small Branded Swift | — | வயல் தாவி | Pelopidas mathias | LC | — | |
| Small Minivet | — | சிறிய மின்சிட்டு | Pericrocotus cinnamomeus | LC | — | |
| Small Pratincole | — | சின்னத்தோல் குருவி | Glareola lactea | LC | — | |
| Smallspotted Dart | — | — | Trachinotus baillonii | LC | — | |
| Smalltooth Emperor | — | — | Lethrinus microdon | LC | — | |
| Smith’s Fangblenny | — | — | Meiacanthus smithi | LC | — | |
| Snakehead Gudgeon | — | — | Ophiocara porocephalum | LC | — | |
| Snakeskin Gourami | — | — | Trichopodus pectoralis | LC | — | |
| Snowflake Moray | — | — | Echidna nebulosa | LC | — |
