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Vertebrate Natural History - Mouth Shapes

Mouth Shapes Terminal --When upper and lower jaws meet at anterior extreme of the fish Usually active predators that run down prey e.g., Subterminal/Inferior --When upper jaw extends beyond lower jaw Usually benthic feeders that pick prey on or out of substrate e.g., Deep-sea spiny eels Superior --When lower jaw extends beyond upper jaw Usually benthic "sit and wait" predators or surface feeders e.g., Monkfishes, Topminnows Fish Scales Ganoid -- Rhomboid shape and composed of hard inorganic substance called ganoine e.g., Gars, Sturgeons ctenoia Ctenoid -- Characterized by ctenii -- small spines on trailing edge of the scale Reduce laminar flow and aid in swimming e.g., Basses, Sunfishes External characteristics of a generalised bony fish spinius dorsal fin origin of dorsal fin dorsal surface nosterior anterlor soft dorsal lfin nape coudal fin scutes eye latera /line nostril mouth glll cover nm -pectoralfin chin- coudal peduncle base of pectoral fin anus barbel ventral surtace anal fin Reproduced with permission from the Museum of New Zealand ventral or pelvic fin