This is not a bag of smelt.
Fish are notoriously insufficiently labeled. And sometimes, they are entirely mislabeled, as we will see in this example.
On my last trip to our local Asian supermarket, I also picked up this package of frozen fish. Smelt is one of my favorite fish to eat — various smelt species are eaten in many countries, often deep-fried or grilled whole, with female fish often full of rich, creamy eggs inside. So I was excited to bring this batch home and have a smelt species to write about.
Although the packaging said “smelt” in three different languages — English, French and Chinese — when I opened the bag, something else fell out.
The fish in my hand had two dorsal fins — the fins along the fish’s back. Both, however, were supported by thin bones, or rays.
True smelts belong to Family Osmeridae and various other families in Order Osmeriformes. True smelts only have one dorsal fin with rays, while the second dorsal fin, located closer to the tail, looks more like a little fleshy nub. This type of fin is called an adipose fin — you can also find them on salmon, trout and most catfish.
The dorsal fins were a good clue, and narrowed down the possible families of fishes. Also helpful was the country of origin: wild-caught in Peru.
A round of searches online revealed the fish’s identity: the Chilean or Peruvian silverside (Odontesthes regia), a small fish topping at 5 inches (13 cm) native to the estuaries and coasts of Chile and Peru.
Silversides belong to Order Atheriniformes, which also contains the freshwater rainbowfishes popular in the aquarium trade, as well as the odd priapiumfishes, in which the male fish has a sex organ extending from underneath its head.
Less bizarre but no less interesting a relative is the California grunion (Leuresthes tenuis), famous for its spawning orgies onto sandy beaches at night. The California grunion is a close relative of our Peruvian silversides, both belonging to the silverside family Atherinopsidae.
In Peru, the Peruvian silverside is referred to as pejerrey, a name also used elsewhere in South America for other silverside species. Pejerrey is “highly appreciated in South America, especially in Peru and Chile where it is considered a fish of excellent gastronomic quality” (Orellana and Toledo 2007). Online recipes show photos of pejerrey sandwiches, and as my Peruvian colleague from graduate school Martin Romero Wolf tells me, “We eat it deep fried or in ceviche. It good and cheap. Has a sort of strong taste.”
So pejerrey is what we will call it, to reflect its Peruvian heritage. Now for the fun of it, let’s check on the other names on the the package label.
Eperlan, the French word used, is the name for the European smelt (Osmerus eperlanus) of northern European lakes and seas — a true smelt.
香魚, the Chinese characters used, refers to yet another species on yet another continent, specifically the sweetfish (Plecoglossus altivelis) of East Asian rivers and seas. It is known as ayu in Japan — and it is also a true smelt.
One label. Three names. Three species. Three continents.
But what’s the difference, really? All are small, silvery fish what roam the seas and estuaries, and if you wanted to sell pejerrey to audiences unfamiliar with names like “pejerrey” or “silversides”, you might choose to grab another name that the local audience has context of.
Yet here lies the inevitable disappointment. Those who know the difference will be disappointed. There are indeed differences among the three fish — pejerrey, éperlan, ayu — and having had both ayu and pejerrey, I can say that they differ greatly in their flavors and tastes. Not to speak of their ecologies and cultural contexts.
So I choose not to be oblivious to mislabeled fish. If these days we can make a big fuss about the difference between kale varieties or grape varietals, I think the better thing to do is to better know a fish — and appreciate their splendid biological and gastronomical diversity.
Odonteshes regia (Humboldt, 1821)
Pejerrey (click for names in other languages)
FishBase Page: http://fishbase.org/summary/8172
— Ben Young Landis