When I was reading everything I could find about nature as a kid in the 1970s, I remember seeing the figure 300 a lot, as in 300 total species. Figures like 320-330 was pretty common. But no one - not an amateur, not an ichthyologist - in those days would have claimed there were 500+.
Well, one official count stands at 512. That may be a little high or low, given the differences of opinion in what's a separate species. But Douglas Long, writing in DeepSea News, counted six new species in 2015 alone. These include the small but incredibly cool ninja lanternshark (
The fast, powerful shortfin mako has the classic look people think of when they hear "shark." (NOAA)
The U.S. government lists the basking shark, a harmless filter-feeder the size of a small bus, as a "species of concern" because of exploitation for its fins. (NOAA)