Rachel Arnold is one of the world’s two frogfish scientists. The other is her professor at the University of Washington, where she’s currently working toward a Ph.D. So far, Arnold, 32, is credited with discovering two new frogfish species.

Q: First off, how many frogfish species exist?
A: Right now, there are 49.

Q: Right now?
A: New species are being described — that is, becoming officially named and recognized — all the time. Some as-of-yet unknown species have been collected but remain sitting in collections until funding becomes available to ship them to labs.

Q: Were you tempted to name either of your discoveries after yourself?
A: No. That’s poor form. It’s an honor to have a species named after you, but it wouldn’t be cool to name it after yourself. I named one after my mentor, Ted Pietsch, so that one is Pietsch’s frogfish.

Q: What’s been your most amazing encounter?
A: Frogfish behavior is so cool, but it’s really hard to see anything other than them just sitting there. That’s where recreational divers have played a huge role. One diver filmed the psychedelic frogfish bouncing off the reef using its pelvic fins to swim. We know frogfish swim via fluttering and a jet propulsion unique to their species, but this pelvic-fin swimming was all new.

Q: Anything else?
A: When frogfish mate, the male pushes the female toward the surface, where she releases a raft of eggs. We didn’t know until we saw on YouTube that the male spins the raft before he performs his role.

Q: You dive all over in the name of science. Any favorite spots?
A: I always steer divers to a town in southern Australia called Edithburgh — it’s an area that’s so untouched. There you’ll find not only a huge variety of frogfish, including the tasseled anglerfish, but leafy sea dragons and pajama squid.

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