DIVE DRY WITH DR. BILL #808: FENDING OFF THE SABERTOOTH
My early ancestors feared cats... big cats known as sabertooths with large canine teeth. Yes, contrary to many popular tales they were cats rather than tigers. Perhaps the best known of the several species that existed was Smilodon fatalis. No doubt several of my predecessors on this planet sadly learned why the species name was fatalis. These cats were social hunters and could take down elephants and mammoths so early Homo sapiens weren't too much of a challenge except when armed with a stout spear. I've often wondered if I received some of their genetic material due to my large canines or fangs.
My readers know that I rarely write about mammals unless they are seals, sea lions, dolphins or whales. However, there is a vicious group of small fish known as sabertooth or fang blennies that many marine critters fear. I have seen members of this group of species in a number of dive destinations throughout the world. I have filmed them attacking fish including angelfish, barberfish, boxfish, wrasses and even morays and stingrays!
My first encounter was years ago in the Gulf of California (aka Sea of Cortez), Mexico. I was serving as marine biologist and underwater videographer on several Lindblad Expeditions cruise ships, primarily in the islands off the coast from Loreto to La Paz. I noticed these small, thin fish attacking several fish as well as hiding in empty worm and snail tubes. I quickly found out they were sabertooth blennies (Plagiotremus azaleus) thanks to the field guides on board.
Now attacking a relatively defenseless species like an angelfish is one thing. To watch them swim rapidly up to and bite a blue boxfish, moray or a stingray was another. They nip small bits of flesh off the target fish as well as "tasty" tidbits of mucus (yech). I have also read that they will eat fish scales (and not the ones used to weigh your catch). The skin of a boxfish is armored and also exudes a toxin when they are disturbed. Morays could make a quick snack out of the much smaller blennies.
One day I was filming a bullseye stingray when it started jumping about as if it was being attacked, and then buried itself in the sand. I couldn't tell what was hapening thru the small viewfinder of my video camera. When I reviewed the footage on my computer screen, I was surprised to find the stingray was being attacked by a sabertooth blenny. The species in Mexico takes advantage of an unrelated fish, the rainbow wrasse (Thalassoma lucasanum), which is similar in size and appearance. It joins small groups of the wrasses so it can sneak around often undetected by its target.
Sabertooths are home bodies when they aren't out causing havoc for other species. They insert their sleek bodies into abandoned worm and snail tubes with only their head poking out. I've seen this in other related species throughout the world as well. The female lays her eggs inside the male's tube and he is stuck with egg care until they hatch. The larvae are planktonic and drift a while in the currents to see the world before settling down.
On a number of my exotic dive trips to warm, tropical waters I have seen other species which are generally referred to as fangblennies. The yellowtail fangblenny (Meiacanthus atrodorsalis) was occasionally captured on film while in the Philippines. It is also known as the lyretail, forktail or eye-lash harptail fang blenny and a host of other common names. It apparently feeds on zooplankton and bottom-dwelling invertebrates using two enormous (relative to its small size) fangs, but they are used for defense rather than feeding.
While diving in my favorite destination, Palau, I had several chances to video the bluestriped fangblenny (Plagiotremus rhinorhynchos). It, too, has a number of common names so stick with the scientific one. Like the fangblenny in Mexico, it mimics the common bluestreak cleaner wrasse (Labroides dimidiatus). Many host fish come to cleaning stations to have parasites removed by these cleaners. The fangblenny hangs with them and the fish that come to be cleaned may not know the difference until the fangblenny darts in and nips them.
And a few years ago I encountered the scale-eating sabertooth blenny (Plagiotremus tapeinosoma) in the Egyptian Red Sea. As its common name suggests, it darts out to grab the scales of other fish. Somehow that does not sound very appetizing or nutritious, but perhaps that's a result of cultural differences. However, I have a feeling it also ingests skin and mucus like its relatives.
Fortunately divers have little to fear from these vicious sabertooths. They will occasionally nip a diver, but it is generally a nuisance rather than a PITA (or elsewhere). I was surprised to learn that some of these blennies use an interesting strategy. Some species of fish develop painful toxins as a form of defense. Some members of this group of fish do the opposite. They create an opioid-like venom that acts like heroin or opium. When swallowed by a predator, these fangblennies release the substance causing their nemesis to become disoriented and they are often spit out. Next time I have surgery, I may ask my doctor to give me a dose to dull the pain (although it will have no effect on the bill I receive).
© 2019 Dr. Bill Bushing. For the entire archived set of over 800 "Dive Dry" columns, visit my website Star Thrower Educational Multimedia (S.T.E.M.) Home Page
Image caption: Yellowtail fangblenny from the Philippines and bluestriped fangblenny from Palau; scale-eating sabertooth from Egypt and the Mexican species of sabertooth from the Sea of Cortez.
My early ancestors feared cats... big cats known as sabertooths with large canine teeth. Yes, contrary to many popular tales they were cats rather than tigers. Perhaps the best known of the several species that existed was Smilodon fatalis. No doubt several of my predecessors on this planet sadly learned why the species name was fatalis. These cats were social hunters and could take down elephants and mammoths so early Homo sapiens weren't too much of a challenge except when armed with a stout spear. I've often wondered if I received some of their genetic material due to my large canines or fangs.
My readers know that I rarely write about mammals unless they are seals, sea lions, dolphins or whales. However, there is a vicious group of small fish known as sabertooth or fang blennies that many marine critters fear. I have seen members of this group of species in a number of dive destinations throughout the world. I have filmed them attacking fish including angelfish, barberfish, boxfish, wrasses and even morays and stingrays!
My first encounter was years ago in the Gulf of California (aka Sea of Cortez), Mexico. I was serving as marine biologist and underwater videographer on several Lindblad Expeditions cruise ships, primarily in the islands off the coast from Loreto to La Paz. I noticed these small, thin fish attacking several fish as well as hiding in empty worm and snail tubes. I quickly found out they were sabertooth blennies (Plagiotremus azaleus) thanks to the field guides on board.
Now attacking a relatively defenseless species like an angelfish is one thing. To watch them swim rapidly up to and bite a blue boxfish, moray or a stingray was another. They nip small bits of flesh off the target fish as well as "tasty" tidbits of mucus (yech). I have also read that they will eat fish scales (and not the ones used to weigh your catch). The skin of a boxfish is armored and also exudes a toxin when they are disturbed. Morays could make a quick snack out of the much smaller blennies.
One day I was filming a bullseye stingray when it started jumping about as if it was being attacked, and then buried itself in the sand. I couldn't tell what was hapening thru the small viewfinder of my video camera. When I reviewed the footage on my computer screen, I was surprised to find the stingray was being attacked by a sabertooth blenny. The species in Mexico takes advantage of an unrelated fish, the rainbow wrasse (Thalassoma lucasanum), which is similar in size and appearance. It joins small groups of the wrasses so it can sneak around often undetected by its target.
Sabertooths are home bodies when they aren't out causing havoc for other species. They insert their sleek bodies into abandoned worm and snail tubes with only their head poking out. I've seen this in other related species throughout the world as well. The female lays her eggs inside the male's tube and he is stuck with egg care until they hatch. The larvae are planktonic and drift a while in the currents to see the world before settling down.
On a number of my exotic dive trips to warm, tropical waters I have seen other species which are generally referred to as fangblennies. The yellowtail fangblenny (Meiacanthus atrodorsalis) was occasionally captured on film while in the Philippines. It is also known as the lyretail, forktail or eye-lash harptail fang blenny and a host of other common names. It apparently feeds on zooplankton and bottom-dwelling invertebrates using two enormous (relative to its small size) fangs, but they are used for defense rather than feeding.
While diving in my favorite destination, Palau, I had several chances to video the bluestriped fangblenny (Plagiotremus rhinorhynchos). It, too, has a number of common names so stick with the scientific one. Like the fangblenny in Mexico, it mimics the common bluestreak cleaner wrasse (Labroides dimidiatus). Many host fish come to cleaning stations to have parasites removed by these cleaners. The fangblenny hangs with them and the fish that come to be cleaned may not know the difference until the fangblenny darts in and nips them.
And a few years ago I encountered the scale-eating sabertooth blenny (Plagiotremus tapeinosoma) in the Egyptian Red Sea. As its common name suggests, it darts out to grab the scales of other fish. Somehow that does not sound very appetizing or nutritious, but perhaps that's a result of cultural differences. However, I have a feeling it also ingests skin and mucus like its relatives.
Fortunately divers have little to fear from these vicious sabertooths. They will occasionally nip a diver, but it is generally a nuisance rather than a PITA (or elsewhere). I was surprised to learn that some of these blennies use an interesting strategy. Some species of fish develop painful toxins as a form of defense. Some members of this group of fish do the opposite. They create an opioid-like venom that acts like heroin or opium. When swallowed by a predator, these fangblennies release the substance causing their nemesis to become disoriented and they are often spit out. Next time I have surgery, I may ask my doctor to give me a dose to dull the pain (although it will have no effect on the bill I receive).
© 2019 Dr. Bill Bushing. For the entire archived set of over 800 "Dive Dry" columns, visit my website Star Thrower Educational Multimedia (S.T.E.M.) Home Page
Image caption: Yellowtail fangblenny from the Philippines and bluestriped fangblenny from Palau; scale-eating sabertooth from Egypt and the Mexican species of sabertooth from the Sea of Cortez.
