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              Shortnose Boxfish (Rhynchostracion nasus) 
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              Shortnose Pufferfish (Canthigaster epilampra) 
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              Shy Hamlet (Hypoplectrus guttavarius) 
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              Sidespot Wrasse, Male (Pseudojuloides mesostigma) 
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              Silverspot Squirrelfish (Sargocentron caudimaculatum) 
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              Singapore Angelfish (Chaetodontoplus mesoleucus) 
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              Singular Bannerfish (Heniochus singularis) 
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              Six Line Wrasse (Pseudocheilinus hexataenia) 
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              Sixbar Angelfish, Adult (Pomacanthus sexstriatus) 
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              Sixbar Angelfish, Juvenile (Pomacanthus sexstriatus) 
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              Skunk Clownfish (Amphiprion akallopisos) 
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              Skunk Tilefish (Hoplolatilus marcosi) 
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              Sleeper Banded Goby (Amblygobius phalaena) 
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              Sleeper Blue Dot Goby (Valenciennea sexguttata) 
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              Sleeper Gold Head Goby (Valenciennea strigata) 
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              Sleeper Mural Goby (Valenciennea muralis) 
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              Sleeper Railway Glider Goby (Valenciennea helsdingenii) 
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              Sleeper Striped Goby (Valenciennea longipinnis) 
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              Slender-Spined Globefish Pufferfish (Diodon nicthemerus) 
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              Slingjaw Wrasse (Epibulus insidiator) 
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              Slippery Dick Wrasse (Halichoeres bivittatus) 
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              Slippery Dick Wrasse, Juvenile (Halichoeres bivittatus juv) 
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              Small Mouth Grunt (Haemulon chrysargyreum) 
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              Smalltail Pencil Wrasse, Male (Pseudojuloides polackorum) 
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              Smith's Blenny (Meiacanthus smithii) 
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              Smith's Damselfish (Pomacentrus smithi) 
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              Smokey Damselfish (Pomacentrus sp. (P. chrysurus or P. littoralis)) 
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              Smooth Trunkfish (Rhinesomus triqueter) 
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              Snooty Wrasse (Cheilinus oxycephalus) 
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              Snow Onyx Clownfish (Amphiprion ocellaris x percula)