Excerpts from Jim Conrad's
from the March 8, 2015 Newsletter issued from Río
Lagartos, on the north-central coast of Yucatán, MÉXICO
At low tide Rayo and I were wading ankle-deep in a Shoalgrass bed that normally lay too deep for such exploration. Spotting a funny looking fish nicely camouflaged atop the mud among Shoalgrass leaves, Rayo scooped the critter into the cut-off bottom of an old Purex jug. That's the three-inch-long (8cm) fish above.
It almost looks like a catfish, but note the long fin atop the body, the dorsal fin, which catfish don't have. Rayo said he'd met this species before, because one day his barefooted brother Jorge stepped on one, causing his foot and lower leg to swell and hurt for three or four days. Therefore, instead of taking the fish into his hand for a better view, unceremoniously he dumped it onto an alga-encrusted rock barely poking from the water. To our surprise, the fish quickly stood itself right-side-up, supporting its body with its side, or pelvic, fins, as if it had a mind to walk off with them. You can see this below:
In that picture you can see that something funny is going on with the eye. Before flipping the fish back into the water I got the close-up eye shot shown below:
It was hard to identify this fish, but it appears to be the rather common Spotted Scorpionfish, SCORPAENA PLUMIERI. My difficulty arises from the fact that the species' appearance changes as it ages. The vast majority of pictures of this species on the Internet show adults, and we have a young one. Spotted Scorpionfish reach almost 18 inches in length (45cm), and can weight nearly 3½ pounds (1.6kg). As Spotted Scorpionfish age and grow, their body surface acquires an impressive collection of warts, bumps and fleshy appendages that contribute to the fish's camouflage, making it look like an alga-encrusted rock. Also, I read that normally the fish is rusty hued, but in shallow water, where we found ours, it becomes grayish, like ours. Some big Spotted Scorpionfish are surprisingly brightly colored and outlandishly shaped. You might enjoy seeing an older one photographed in Honduras at http://www.flmnh.ufl.edu/fish/gallery/photoout.asp?id=6822.
TheDivingBlog.Com website said that scorpionfish are members of "the infamous scorpionfish family." "Infamous," probably because The Scorpionfish Family, the Scorpaenidae, includes many of the world's most venomous species. As Jorge can testify, scorpionfish have venomous spines on their backs. The family also may be "infamous" because among its members are the Lionfish, an invasive species native to the Indo-Pacific, currently threatening coral reefs in our area. One study suggests that they may ultimately decrease Atlantic reef diversity by up to 80%.
But that's invasive Lionfish, and here we have the native Spotted Scorpionfish, which does nothing more aggressive than envenom any creature that mistreats it. Normally Spotted Scorpionfish feed on crustaceans and other smaller fish, using the lie-in-wait strategy. They suck in small prey who wander too close to their mouths by simply snapping open their big mouths incredibly fast, causing water containing critters to rush into the vacuum created by the sudden opening. Predators of Spotted Scorpionfish include large snappers, sharks, rays and moray eels.
And what of those eyes? Lots of people take close-up pictures of the eyes, but so far I can't find any explanation for their strange appearance. I do read that among scorpionfish species eyes often are set atop the head, enabling them to see what's going on when they bury themselves in sand, with their eyes poking out.