Honeycomb Cowfish in Cozumel July 20 2021

The afternoon dive on July 20th was relaxing. There was very little current and we were at a shallow dive site. This meant we could go slower and spend more time looking at sea life.

I was fortunate enough to encounter a Honeycomb Cowfish near one of the coral formations. I have always liked this fish because of the unusual body shape and their honeycomb color pattern.

The website mexican-fish.com tells us,

The Honeycomb Cowfish, Acanthostracion polygonius, is a member of the Boxfish or Ostraciidae Family, that is also known as the Cowfish and the Trunkfish and in Mexico as torito hexagonal. Their common name stems from the honeycomb like pattern and “horns” with sloped face and pronounced forehead.

https://mexican-fish.com/honeycomb-cowfish/

The article taught me that their, “deep triangular shaped body that is enclosed is a “carapace” made up of hexagonally-shaped plates fused together to form a shell or true carapace.”

The Florida Museum Website has more detail about the carapace. They describe it as, “consisting of thickened hexagonal scale plates that are firmly attached to each other with the exception of the cheeks to allow for respiration movements. There are openings in the carapace for the mouth, eyes, gills, fins, and the flexible caudal peduncle.”

Towards the end of the article they say, “Larger fish are potential predators of the honeycomb cowfish, however it may be undesirable as a prey item due to its protective external armor, the carapace.”

Whitespotted Filefish in Cozumel on July 19 2021

During one of the dives on July 19th I encountered a pair of Whitespotted Filefish.

A page from the Dive Paradise website tells us, “They have scales, although very small, and feel like sandpaper – not dissimilar to a shark’s skin. This roughness is how the Filefish got its name. Reportedly their dried skin was once used to finish wooden boats.”

They go on to say,

Every Filefish has a sharp spine on its head just above its eyes. It erects the spine when threatened as a defensive move. Its primary defense is to erect its dorsal and pectoral fins plus the spine to make it difficult for a predator to eat or to extract from its hiding place if back in a little cave.

https://diveparadise.com/2017/11/05/american-whitespotted-filefish-cozumel-reefs/

It looks like I made the darker filefish nervous since it’s spine was up as it approached me, and what I assume is it’s mate. Since both sexes can change color, that’s not a good way to tell which is the male and which is the female. The website says, “It is difficult to differentiate between males and females. The male fish are said to have slightly larger appendages extending from their bodies at the base of their tails.”

When the orange colored filefish turned it’s tale towards me I can see what I think are the “appendages extending from their bodies at the base of their tails.” Although it’s still difficult to tell for sure, this would make the orange colored filefish the male.

Foureye Butterflyfish in Cozumel, July 19, 2021

A tropical fish that I enjoy watching is the Foureye Butterflyfish since they are often in pairs. The Florida Museum website tells us, “This is one of the few fish that seems to mate for life.”

The website continues to say,

Male and female foureye butterflies form pairs early in life. These pairs can be long lasting, suggesting that a monogamous relationship may exist between the pair members. If the two fish get separated, one partner will swim upward for a better view in an effort to rejoin the other partner. Courtship between the two is prolonged and energetic. Often the fish will circle each other, head to tail, until one fish breaks and runs, with the other close behind. They will chase each other all about the reef, and chase away any lone foureye that approaches them. Actual spawning takes place at dusk. The female releases from 3000 to 4000 eggs a night. The eggs are small, pelagic, and hatch within a day.

https://www.floridamuseum.ufl.edu/discover-fish/species-profiles/chaetodon-capistratus/

Although the fish are beautiful, take a look at how healthy the coral is that they are swimming near! After seeing so many diseased and dead coral in Florida, healthy coral is a welcomed sight. Although coral identification can be a challenge for me, based on the star coral identification page on the scubadiverslife.com website, I think we are seeing Mountainous Star Coral and Lettuce Coral.

Queen Triggerfish in Cozumel, Mexico on July 21, 2021

It took me most of the week to get a good video of a Queen Triggerfish. Notice how it changes color as it swims by. Since many of my favorite fish can change color, I became interested in learning how it happens.

The New World Encyclopedia tells us,

Chromatophore is a pigment-containing and light-reflecting cell, found in various invertebrate and cold-blooded vertebrate animals, that can help bring about changes in color or brightness in the organism. Among animals with such cells are various crustaceans, cephalopods, amphibians, fish, and reptiles. Through aggregation or dispersion of the pigment and reorientation of reflective plates in single cells (in most animals) or through the muscular movement of complex chromatophore organs (in cephalopods), the color or brightness of the entire organism or part of the organism can change, which is useful for camouflage, signaling, temperature regulation, and protection from radiation.

https://www.newworldencyclopedia.org/entry/Chromatophore

It looks like this Queen Triggerfish was changing color to blend with the surroundings for camouflage.