We're looking at the 15 members of the genus Pterois - shallow water fish found off Indo-Pacific coasts and attaining a length somewhat more or somewhat less than 30 cm (1 foot).
The most immediate thing you notice is their unique, savage beauty.
They are utterly festooned with all manner of elaborate, decorative, sticky-out bits. It's all a bit confusing and surely, an interference and burden in the Lionfish's life. It looks like running in stiletto heels or something.
At least some of these adornments don't seem to serve any obvious purpose. That's those long tentacles above the eyes. Some of the other stuff is a little more clear.
That extravagant mane of pectoral fins isn't venomous. The dorsal, pelvic and anal fins however, are. They have fin rays which end in a sharp point, with venom glands at the base. This venom has been shown to weaken the heart of some animals, causing a drop in blood pressure. In humans it can cause terrible pain, vomiting and fever, but death is rare.
|Broadbarred Firefish, aka Spotfin Lionfish|
Top view, head on the bottom right.
Lionfish are voracious predators of small fish and invertebrates. Those gigantic pectoral fins are opened out wide to corner prey and cut off escape. With remarkable control over their swim bladder they can get into position, pointing up, down and even upside down to ready the attack. They then swallow their victim whole with unbelievable speed.
You can imagine the terrible problems that could occur if someone unthinkingly emptied their fish tank and threw a hungry, venomous predator into a non-native ocean.
Well, you're in luck! Because you don't have to imagine.
Having been spotted off the east coast of the US in 2002, the Red Lionfish (Pterois volitans) has since spread from North Carolina all the way down to the Caribbean. Outliers have even been found off New York and Bermuda, perhaps after travelling on the Gulf Stream when they were tiny larvae.
It also helps that they can produce up to 15,000 eggs at a time. It occurs after complicated courtship rituals which no-one seems to talk about. (They are "not well documented". Pro lingo!) It may be at this time that those tentacles have some sort of use. Perhaps facial tentacles are a lot more sexy than I've ever considered.
Studies of the Red Lionfish indicate that they may produce eggs every month all year round. Or maybe the observers have simply been fooled by the indomitable rise of this ravishing fiend. Either way... oh dear.
Image: brian.gratwicke via Flickr
Exquisite and excruciating.
A mixed blessing.