bar:eratopįrom: -65.5 till: -23.03 color:paleogene text: Paleogeneįrom: -23.03 till: -2.588 color:neogene text: Neogeneįrom: -2.588 till: 0 color:quaternary text: Q.Īlign:left fontsize:M mark:(line,white) width:5 anchor:till align:leftĬolor:eocene bar:NAM1 from: -11.6 till:Đ text: Astroscopusįrom: -0.0117 till: 0 color:holocene text: H. ScaleMinor = unit:year increment:1 start:-65.5 ScaleMajor = unit:year increment:5 start:-65.5 PlotArea = left:10px bottom:50px top:10px right:10px ImageSize = width:1000px height:auto barincrement:15px They are unique among electric fish in not possessing electroreceptors, meaning that they do not use an electric sense to locate prey. These two genera within stargazers represent one of eight independent evolutions of bioelectrogenesis. Astroscopus species have a single electric organ consisting of modified eye muscles, while Uranoscopus species have theirs derived from sonic muscles. The species within the genera Astroscopus and Uranoscopus can also cause electric shocks. Stargazers are venomous they have two large venomous spines situated behind their opercles and above their pectoral fins. Lengths range from 18 up to 90 cm, for the giant stargazer Kathetostoma giganteum. Both the dorsal and anal fins are relatively long some lack dorsal spines. Some species have a worm-shaped lure growing out of the floors of their mouths, which they can wiggle to attract prey's attention. Their usual habit is to bury themselves in sand, and leap upwards to ambush prey ( benthic fish and invertebrates) that pass overhead. In addition to the top-mounted eyes, a stargazer also has a large, upward-facing mouth in a large head.
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