'Lachrymal Saber' revealed!


#1

Because why wouldn’t a fish have a couple of switchblades hidden in its face?

image

(Subject requests ‘delightful creatures’ classification; suggests that organisms that use their lachrymal features for crying would do well to comply.)


#2

This maxillary rotation results in a subsequent rotation of the lachrymal that we hypothesize reduces predation on stonefishes.

Yeah, I guess it might do just that…

On the other hand:

Smith isn’t sure why the fish evolved this trait. The obvious assumption is it’s defensive, given the projected spines expand the width of the head, making the fish harder to swallow and more likely to puncture a would-be predator. Similar defensive measures exist: the deep-sea lanternshark, for example, has glowing “lightsabers” on its dorsal spine that are believed to defend against predators. But Smith hasn’t seen the lachrymal saber used defensively, except in photographs of mail-cheeked fishes getting eaten.

“I went into this assuming it was an anti-predator, complex anatomical thing that grew that way and now as every day goes on, I start questioning that more and more,” Smith says. “Part of it is I can never get the stupid things to do it … I mean you would think if it was just anti-predator, if I bumped the tank they would immediately get them out.” The other option, he says, is that it might be for attracting mates, though he points out that both genders appear to have the sabers.

In other words, for now, the eye spike is still a mystery.


#3

Clown loaches, which are popular aquarium fish, have similar spines:


#4

Do they operate under the motto “Clown Loach: who’s laughing now?”