One of the iconic traditional dishes of Brazil's Northeastern cultural region (Nordeste in Portuguese) is a seafood soup or stew called "caldo de sururu." It's a simple dish, a peasant dish, and it's normally served in waterfront bars, or by vendors on Brazilian beaches. It's delicious and filling, and locally it is reputed to have therapeutic effects in regards to hangovers, and enhancing effects for male potency. I've eaten the soup myself, but cannot vouch for either of these effects!
It's clear, when eating caldo de sururu, that sururu is some sort of shellfish, although the sururu have already been shelled in the preparation of the caldo, so there is not much in the way of hints to help one identify the animal itself. It's as if one tried to picture what a clam looked like from eating clam chowder. I was curious exactly what a sururu was, and no one here could exactly tell me. So I began to do some research using trusty (?) tools like Wikipedia and Google.
The sururu, it turns out, is a bivalve mollusk like clams, oysters and mussels. I had previously thought that was probably the case, as one nickname for sururu locally here in Fortaleza is "the poor man's oyster (a ostra dos pobres). Google images gave me this photo of a sururu, and it certainly looked like some sort of mussel to me:
I also found a photo of sururu once it had been shelled, and it continued to look like a mussel:
After some searching, I discovered the taxonomic name for the sururu - Mytella charruana. From there, I knew I could track it down outside Brazil, and outside the gastronomic universe. When I checked for Mytella charruna in Google Images, I found this intriguing photo:
Why was there a red circle around the sururu and a red band through it? What was/is the problem? Time for some more internet research. I soon discovered why. If you'd like to know what the problem is, click on "read more" below.
Googling Mytella charruana, I discovered first that sururu does have a common name in English: Charru Mussel. And I discovered why I'd found the "banned" image of the sururu on a site called GIST - The Global Invasive Species Team. On their page of alerts I found this:
More details about the sururu as an invasive species can be found on the same site. From everything I've been able to read on Brazilian websites, there is no problem with overpopulation of sururu here in Brazil - but this is its natural habitat and there are probably natural limitations on population. Once again it appears that when an animal species moves or is moved to a new environment it has the potential to increase population dramatically and to the detriment of local species.This tropical mussel has been found in the Mosquito Lagoon portion of the Indian River Lagoon, Florida. All indications are that this mussel is reproducing---nearly 600 individual mussels have been collected from the lagoon. This mussel could displace natives and adversely affect commercially important oysters. It has now also been found in Georgia!
So if you do happen to come to Brazil and discover that you love caldo de sururu, please don't take some live specimens home with you to introduce into your local waterways. Enjoy them here, and go home empty-handed!
There is a recipe for caldo de sururu in the following posting.