#labridae

Slippery Dick (Halichoeres bivittatus), family Labridae, order Labriformes, found in the tropical western Atlantic

Feel free to taste.

Like many wrasses, this fish starts life as a female, and becomes male later in life.

A ringtail Maori wrasse (Oxycheilinus unifasciatus) in Honaunau Bay, Hawai'i

NEW DISCOVERIES ON WRASSES USING TOOLS TO CRACK OPEN PREY

New observations have significantly expanded our understanding of anvil use in wrasses, particularly among South American wrasses, Halichoeres species. This tool-use behavior, in which wrasses use hard surfaces to break open prey, was once thought to be rare and restricted to a few species and locations. However, recent findings from Southern Brazil and the Turks and Caicos Islands indicate that anvil use is far more widespread than previously recorded. Wrasses have been observed using a variety of hard surfaces, including rocks, rubble, and even live conch shells, to crack open crabs, sea urchins, and molluscs, demonstrating remarkable behavioral flexibility.

A key feature of this behavior is its adaptability. Wrasses do not rely on a single anvil or striking point during an event; instead, they are highly opportunistic, shifting between different surfaces as needed. This flexibility enables them to exploit a diverse range of prey and enhances their foraging efficiency. Notably, no strong preference for one side of the body was observed during anvil use, suggesting that wrasses are not lateralized in the same way that tool-using primates often are.

-Sequence of a yellowhead wrasse, Halichoeres garnoti, striking a brittle star arm on rubble by swinging its head from the left to the right

The discovery of anvil use in additional wrasse species suggests that this behavior may be far more widespread than previously believed. To fully grasp the extent of anvil use across various species and regions, further focused research is essential. Controlled experiments offering prey to wrasses could yield valuable insights into the evolution of this behavior, its ecological advantages, and its broader evolutionary significance.

video: A yellowhead wrasse (Halichoeres garnoti) cracking open a brittle star to access the meat inside, using rocks and rubbles, and even a live conch, by C.E. O'Brien

Carpenter's flasher wrasse!

Collection of taxidermy fish

Let's Hear it for the Humphead Wrasse

The humphead wrasse, Cheilinus undulatus, is also known as the Māori wrasse, Napoleon wrasse, or the blue- tooth grouper. They can usually be found around coral reefs and steep rocky cliffs in the Indo-Pacific, particularly on the east coast of Africa, the west coast of India, and the tropical waters of southeast Asia and the Great Barrier Reef.

The Māori wrasse gets its name from the distinctive markings that adults carry. Males are blue-green or purple, while females are more often red or orange. Both have unique patterns of lines and dots covering their heads, and stripes running down the rest of their body; early researchers compared the patterns on their heads to the tattoos traditionally used by the Māori people. In addition to its striking coloration, C. undulatus is also known for being the largest member of the wrasse family. Males can reach up to 2 m (6.5 ft) long and weigh up to 180 kg (396 lbs), while females tend to be smaller. Males also have a large 'hump' on their foreheads, hence the name humphead wrasse.

Another feature of note in C. undulatus is the set of large teeth fused into a parrot-like beak. They use this beak to predate upon hard-shelled animals like mollusks, urchins, sea stars, and crustaceans. On occasion, they also feed on smaller fish and moray eels. Due to their size, adults have very few natural predators aside from sharks, but larvae and small juveniles are more often opportunistically hunted by other fish.

Like many coral reef fish, the humphead wrasse is a protogynous hermaphrodite. This means that most individuals begin life as a female, and become male later in life-- known as 'super males', they are larger than males who did not transition. Individuals first become sexually mature at 5-7 years old, and females begin transitioning to male at 9-12 years old. Spawning occurs a few times a year, and during this period over a hundred adults can congregate in an area. The female releases about 20 eggs into the water column, where they are fertilized by her chosen partner. Three to four weeks later, the eggs hatch and the larvae migrate to the nearby reef.

Conservation status: C. undulatus is considered Endangered by the IUCN. Populations have declined due to overfishing and by-catch mortalities, loss of their food sources, habitat destruction, and capture of juveniles for the aquarium trade.

If you send me proof that you’ve made a donation to UNRWA or another organization benefiting Palestinians– including esim donations– I’ll make art of any animal of your choosing.

Photos

Andrew J. Green

Lluís Masuet