Two puzzlers from the northern end of the Sea of Cortez

[Sorrows]

Not sure if anybody here can help, because all I have is a photo of his home:

Btw, the nests appear perfectly built--using some fairly large pebbles and they went a looonngggg way down. From time to time, I could see the claws--obviously, some sort of shrimp. Another diver suggested a shrimpgoby, but I never saw any fish around. Went searching at night for these things, thinking perhaps they would come out more in the dark, but no dice. Does anybody have any ideas?

Also, is it possible there could be flashlight fish near the surface at night in the Sea of Cortez? After one night dive, when we were already back on the zodiac and had given up our cameras (I didn't even have one with me) we could see a bunch of little flashing lights right next to us in the water. Not phosphorenscence--one diver said they were like fairies...Tinkerbell...right under the surface. I have never seen anything like that before, and the (very experienced) DM did not know what it could be. Honestly, we weren't under the influence of mind-altering drugs and there were several of us who witnessed this display. Any ideas what it could have been?

Thanking you in advance--

 

[Tjack]

Mantis Shrimp???

I see the blue flash on night dives often enough, when I try and track down the source I find Squirrel fish every time.

 

[Sorrows]

Sorry, Tjack, I didn't see your response. Thank you! I think it must have been a dark mantis shrimp? Not a peacock, because I did catch a glimpse of its claws.

As for the little flashing fish--no, it wasn't squirrel fish; they were right near the surface of the water and they were very tiny. Very weird!

Thanks again!