A leerie is a leerie is a leerie, right? Wrong. Turns out there are probably four leerie types and they have all been sharing the same scientific name for way too long.
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Like most people, from time to time I fall down a Google rabbit hole.
Does a platypus have nipples?
What is Duduzane Zuma’s address in Dubai?
What WAS that leaking off Rudy Giuliani’s head?
While all of those subjects and their answers (no nipples; the 18th floor of the Burj Khalifa in Dubai; and liquefied baby seals) are all fascinating, sometimes it’s a case of ask and ye shall not find.
Sometimes a computer says “no”.
The non-answer that’s been bothering me for a while is the Latin name for leervis, Lichia amia. The problem is that there is just one Latin name when there appear to be several species of ‘leervis’, ‘leerfish’ or ‘garrick’ swimming around. Take a search deep dive into the taxonomic background of leervis yourself. What comes back is just Lichia amia. That’s it.
“There is a kind of leervis caught off Gabon that looks different to the one we get down here in South Africa. It’s boxy in shape and spotty.”
Now, I know first-hand that there is a kind of leervis caught off Gabon that looks different to the one we get down here in South Africa. It’s boxy in shape and spotty. There’s also another one that you find in the Mediterranean that looks more like our one but is even bigger. And then, of course, there’s our local leerie, the Crease Fly-smashing, queenfish-like predator of our oceans and estuaries. At a glance it looks pretty similar to the Med version.
I dug around old posts on online fishing forums where I made a little progress, but not enough. Seasoned anglers speculated that there were four distinct leervis – the Mediterranean, the Tropical West African (also found in Northern Angola), the Southern Angolan and the South African. To get some scientific clarity, I mailed Prof. Warren Potts, Associate Professor in the Department of Ichthyology and Fisheries Science at Rhodes University. He roped in his ichthyology colleagues Dr Alex Winkler and Dr Ed Butler, who both work from or with Rhodes University. Our back and forth revealed a few surprises:
SAME SAME BUT DIFFERENT
So, are all Lichia amia alike or are there different species?
Potts had this to say, “There are three populations of warm temperate leervis that are found in South Africa, Namibia and in the Mediterranean. We compared the genetics of the South African and Angolan population and found deep genetic divergence (they are probably separate species). Based on the large differences that we found between the Angolan and South African populations, we also expect the Med fish to be different.”
Ed weighed in with, “I have never experienced the Mediterranean species in the flesh, but have encountered the other three. The species in South Africa and southern Angola pretty much look the same and the Med species fits in here too. The three populations look more or less the same, but may have a number of biological, genetic or other differences and may well be separate species. However, the tropical variant encountered in northern Angola/ Gabon etc. is very different… well, at least in appearance. It has a much deeper body in relation to its length (almost like a West coast steenbras does in comparison with our white steenbras, for example). They also have beautiful markings/dots along their flanks, which our leerie don’t really have. The first time I saw one whilst working from the Kwanza River in Angola, we knew immediately that it was something different and I actually ended up stuffing it into a suitcase in between all my clothes and flying it back to South Africa a few days later.”
Potts says, “In terms of the biology of the tropical leerfish from West Africa, we are really not too sure. For now, we assume that it is similar to the warm temperate species, with spawning at sea, recruitment into estuaries and increasing use of the coastal ocean as they mature. We have no idea of their size at maturity or how fast they grow, but their feeding is probably similar (primarily piscivorous).”
THE ORIGINAL LEERVIS
The funny thing is that it turns out the ‘rare’, ‘new’ (to me), ‘tropical’ leervis that set me off on this taxonomic goose chase is probably the original Lichia amia. The rest of the gang with the shape, colour and lateral lines we know so well, are likely to be the variants.
Potts explains, “The original description of Leerfish (then called Scomber amia) was by Linnaeus in 1758. This was based on a description of a specimen captured in West Africa and is the tropical leerfish. This specimen does not look like the warm temperate leerfish, but someone, at some stage, obviously felt that they were the same species and hence the South African, Angolan and Mediterranean Leerfish have always been called Lichia amia. So, at the moment, we have a taxonomic mess.
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