Little Tunny

Domain: Eukarya
Kingdom: Animalia
Phylum: Chordata
Class: Osteichthyes
Order: Perciforms
Family: Scombridae
Genus: Euthynnus
Species: Euthynnus alletteratus

My husband loves to eat tuna. If he could have it every day, I think he would! Little tunny, or little tuna, is a common species of tuna found in the tropical and subtropical waters of the Atlantic Ocean, the Caribbean Sea, the Gulf of Mexico, the Black Sea, and the Mediterranean Sea.

Euthynnus allettatus can grow up to 48 inches and averages around 20 pounds when fully grown. The fish is has countershading, dark-blue gray coloring on top that fades to a silvery-white toward the belly. It has a torpedo-like shape that cuts down on water resistance, similar to species of sharks and dolphins. The base of the tail is thin, and the tail fin is crescent-shaped, allowing the little tuna bursts of speed to evade predators or to catch its prey.

There are two distinct features that help to identify little tunny. On the dark blue-gray top of the fish are a couple of wavy lines that form unique patterns running from the dorsal fin to the tail fin. The second feature is found underneath the small pectoral fins, five to seven small dots that stand out against the silvery-white.

Little tunny are considered opportunistic feeders, which is just a fancy way of saying that this fish will eat almost anything it can get a hold of. Typically, it will feed on crustaceans, smaller fish, and squid.

There is a wide range of organisms that prey on little tunny, including larger tuna, dolphinfish, swordfish, and various species of sharks.

E. allettatus reproduce between April and November around the Atlantic Ocean. Females will release their eggs into the open water for males to fertilize. Females release their eggs multiple times throughout the reproductive months, and the species can produce almost 2 million eggs per year. Whale sharks have been found in these waters, such as off the coast of Isla Mujeres, looking to gorge themselves on fish eggs.

These fish are very important to the local fisheries, including the West Indies. They’re a good fish to consume; the meat is darker and has a stronger taste than larger commercial tuna, and it can be prepared in a number of ways. Little tunny are also good game fish, because they give fishermen a bit of a challenge.

Their population numbers are good, and the species is considered to be of least concern of extinction by the IUCN Red List. If properly regulated, little tunny would be an excellent species of tuna to introduce to larger markets to ease off the pressure of other, scarcer species of tuna.

Isla Mujeres is on my list of places to go. I’ve already decided that while we’re there we’re going to try locally sourced little tunny, if it’s available. I would love to see if my tuna-loving husband enjoys this species of tuna!

Sources and links:
Reef Fish Identification: Florida Caribbean Bahamas 4th Edition by Paul Humann and Ned Deloach
https://www.floridamuseum.ufl.edu/discover-fish/species-profiles/euthynnus-alletteratus/ ⇐more extensive breakdown of little tunny
https://myfwc.com/wildlifehabitats/profiles/saltwater/tuna/little-tunny/ ⇐ key points
http://species-identification.org/species.php?species_group=fnam&menuentry=soorten&id=1925&tab=classificatie
https://www.fishbase.se/summary/97

Mermaid’s Wineglass

Domain: Eukarya
Kingdom: Plantae
Division: Chlorophyta
Class: Dasycladophyceae
Genus: Acetabularia
Species: Acetabularia acetabulum

Have you ever wondered what kind of glasses Atlanteans drank their wine from? I mean, they were Greek, so they had to love wine. Am I right, Dionysus? Would you say that they’d drink from a Mermaid’s Wineglass?

I know, I know that was a terrible lead in but for some reason I couldn’t resist!

No, Atlanteans would not have drunk wine out of Acetabularia acetabulum (Mermaid’s Wineglass) because the whole species is a little over an inch tall. Though if they could have, that would be the ultimate recyclable glassware—or would that be grassware?

Okay, seriously, I’ll stop.

Mermaid’s wineglass is not a grass, it’s a species of algae that can be found in the Mediterranean, Red Sea, in the Eastern Atlantic Ocean off the coast of North Africa, and in the Indian Ocean. Their preferred habitat is around shallow subtidal rocks submerged in water that’s about 50−77°F, so you can spot them if you’re off diving in the Mediterranean Sea.

The Mermaid’s wineglass is aptly named because it’s shaped like a crude wine glass. The stem on the wineglass appears white, kept standing by the encrusting calcium carbonate on the outside, and a small cup like structure sits at the top. This single-celled alga reproduces by creating cysts in the cup. Once the individual dies and everything else decays, the cysts are released into the water to find a nice, dark place to sit for a bit. After napping for a time, they begin to germinate and grow more wineglasses.

I couldn’t find much more information on this species. I mistook it for a different alga that I came across while diving in Jamaica for one of my college courses. The alga I was thinking of is actually called Mermaid’s Tea Cup, which I’ll talk about in a future post.

There is more than one style of wineglass in the Mermaid line, and you can get it in white or green!

In the Atlantic around Florida and the Caribbean, there are two species of Mermaid Wineglasses. Honestly, they look very similar to me but are different for sure on the genetic level. There’s the White Mermaid’s Wineglass (Acetabularia crenulata) and the Green Mermaid’s Wineglass (Acetabularia caliculus) both of which have the same general shape as Acetabularia acetabulum but have different colors. A.caliculus is greener than A. acetabulum.

Sources:
Ocean: The Definitive Visual Guide made by the American Museum of Natural History
Reef Coral Identification: Florida, Caribbean, Bahamas 3rd edition by Paul Humann and Ned DeLoach