The stargazers are a family, Uranoscopidae (from Ancient Greek οὐρανός (ouranós), meaning "sky, heaven", and σκοπέω (skopéō), meaning "to look"), of perciform ray-finned fish that have eyes on top of their heads (hence the name). The family includes about 51 species (one extinct) in eight genera, all marine and found worldwide in shallow and deep saltwaters.
Description
In addition to the top-mounted eyes, a stargazer also has a large, upward-facing mouth in a large head. Their usual habit is to bury themselves in sand, and leap upwards to ambush prey (benthic fish and invertebrates) that pass overhead. Some species have a worm-shaped lure growing out of the floors of their mouths, which they can wiggle to attract prey's attention. Both the dorsal and anal fins are relatively long; some lack dorsal spines. Lengths range from 18 up to 90 cm, for the giant stargazer Kathetostoma giganteum.
Stargazers are venomous; they have two large venomous spines situated behind their opercles and above their pectoral fins. The species within the genera Astroscopus and Uranoscopus can also cause electric shocks. Astroscopus species have a single electric organ consisting of modified eye muscles, while Uranoscopus species have theirs derived from sonic muscles. These two genera within stargazers represent one of eight independent evolutions of bioelectrogenesis. Uniquely, they are used only for hunting or defence, as the fish does not electrolocate.
Genera
Uranscopidae contains the following genera:
<gallery mode=packed heights=100px>
File:FMIB 45715 Kathetostoma nigrofasciatum.jpeg|Deepwater stargazer<br />(Kathetostoma nigrofasciatum)
File:Northern Stargazer.JPG|Northern stargazer<br />(Astroscopus guttatus)
File:Uranoscopus sulphureus.jpg|Whitemargin stargazer<br />(Uranoscopus sulphureus)
File:FMIB 51513 Star-Gazer Astroscopus y-graecum.jpeg|Southern stargazer<br />(Astroscopus y-graecum)
</gallery>
Timeline
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