(Microdesmidae) General Information: There are 10 genera and over 70 species of dartfishes and wormfishes. They have elongated bodies, deeply embedded scales, and no lateral line. Dartfishes have a vertical mouth (no protrusive lower jaw like the wormfishes) and a subdivided dorsal fin. Many dartfishes have a spike-like anterior dorsal fin. They are small fishes with bright colors. Diet: Zooplankton Final Note: Dartfishes must be kept in aquaria with sealed lids to prevent them from landing on the floor. If metal halide lamps are used over the aquaria, they must be lifted 10 inches above the water (at least) to prevent the dartfishes from being 'fried' on the lamps when they jump.