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Sad news mars this bleak wintry day. The Shedd Aquarium’s beloved Australian lungfish “Granddad” has passed away. Granddad enjoyed basking sluggishly in his shallow pool until he beguiled viewers into not paying close attention to him, then he would rise to the top of his puddle and take a deep gasping (and very audible) slurp of air. Lungfish are said to be among the most endearing of pet fish and Granddad enjoyed it when aquarium keepers gently petted him. He also loved eating a nutritious vegetable paste or clams or shrimp… although his particular favorite was “worm Wednesday”. His diet changed several times during his tenure at the aquarium, as keepers learned more about how to look after him and as standards for lungfish husbandry progressed. In his early days, he ate crayfish gathered from the pond in a local Chicago cemetery!
With his muscular pectoral and dorsal fins, Grandad was quite magnificent, in a torpid way–like an intelligent cucumber spattered with mud and gold. At the time of his passing, he was the oldest fish in any public zoo or aquarium in the world. Shedd acquired him (as a full grown adult) in 1933. After a lengthy trip across the Pacific, he traveled across the United States in 3 days in a specially outfitted life-support railroad car.
A revealing historical passage from the Shedd aquarium’s lengthy and moving obituary describes the excitement over Granddad’s acquisition, “In anticipation of overflow crowds from the soon-to-open Century of Progress International Exposition just south of Shedd, aquarium director Walter Chute had written to the director of the Sydney aquarium with a wish list of fresh- and saltwater species. ‘We are, of course, particularly desirous of securing one or two specimens of Neoceratodus forsteri,’ he wrote, using the lungfish’s scientific name.”
Although these days I am closer to the African lungfish who live at the Bronx zoo, I saw Grandad back in the 90s when I lived in South Chicago and I was duly impressed by him. Indeed, in a memorable conversation during college, a group of my closest friends and I were talking about what we would wish to have as accessories if we were action figures. Although my buddies came up with lots of cool plasma guns, miniature vehicles, and humorous inside joke items, I feel I won the conversation by saying “lungfish.” Reading about Granddad only reinforces this feeling (although possibly these days, the “Wayne” action figure would have an avant-garde flounder rather than a clever lungfish).
Although Grandad was only around a century old when he left this world, lungfish have been here a lot longer. The sarcopterygians are nearly 350 million years old. Living Sarcopterygians include only the coelocanths and lungfish (although all amphibians, reptile, birds, and mammals descend directly from them and could arguably be considered Sarcopterygians). After 8 years of writing, I have been running out of things to say about catfish. Once again, Granddad reminds me that there is an even wider and crazier world of fish out there.
For example, did you know that lungfish have the largest genome among the vertebrates? It takes a lot more information to produce a “Grandad” then it does to make Einstein or Rihanna! Although we will miss our long-lived friend (and his mate, who died in 1980), he is survived by a passel of younger Neoceratodus forsteri, who can still be visited at the aquarium. Additionally the Australians are very protective of their dear lungfish. Although they are rare, the government watches after their habitat quite carefully. With any luck the lungfish in the Shedd aquarium will be around another 84 years, and the ones in Queensland will last another 350 million. Maybe we can take them with us to the stars and start some entirely new tetrapod lineages!
Happy news from the ocean depths: marine biologists have discovered an endearingly cute deep sea octopus in the cold deep ocean waters off the continental shelf of California. The newfound octopus is about the size of a fist and looks a lot like the ghosts from Pac-man. The creatures’ default color seems to be a rich orange-pink. It has big soulful black eyes and little fins atop its head which look like cartoon cat ears.
Stephanie Bush, an octopus scientist (!!!) from the Monterey Bay Aquarium Research Institute has spent nearly a year studying the new octopus which she classifies as belonging to the “flapjack” octopuses (a family of animals which sound like they merit additional attention from Ferrebeekeeper). The genus of the octopus is thus pre-established as “Opisthoteuthis” but she is toying with “adorabilis” as a species name (which sounds like a wise choice in the internet era).
So far very little is known about these cute mollusks which live in coastal Pacific waters at depths between 200 and 600 meters. Every one of the dozen specimens thus far found has been female. According to Bush, “They spend most of their time on the bottom, sitting on the sediment, but they need to move around to find food, [&] mates.” I am curious what the male octopuses are like. I presume they are pink and adorable as well, but sexual dimorphism is not unknown among cephalopods. Also, how widespread are these animals? Do they live beyond the California coast?
We need to know so much more. Dr. Bush needs to get back to work, and we are definitely going to need more pictures!
I have always liked looking at underwater ambush predators like wobbegongs, wolf fish, stargazers, and frogfish. There is something appealing about the way that a pile of pebbles will suddenly resolve into a wide toothy mouth with little pebble eyes. In freshwater environments from Nepal down through India, Myanmar, Bangladesh, and into Indonesia, the niche for highly camouflaged bottom predators is filled by Chaco Chaco, the frogmouth catfish.
The frogmouth catfish grows to a size of 8 inches (20 centimeters) and feeds on tiny shrimp and minnows. The animal is mostly head and can swallow creatures nearly as large as itself. Although the frogmouth catfish is already camouflaged, it prefers to bury itself in the mud or sand so that only its tiny black eyes protrude from the substrate.
The catfish are extremely committed to their camouflage and even when captured they will not move (although they growl menacingly when removed from the water). When kept in aquariums they rapidly raise the acidity of the tank which suggests that they either have potent gastric juices (for digesting large prey) or they might emit an unpleasant taste. Aquarium keepers sometimes keep the little predatory catfish in tanks which appear to be empty except for a blank spot of mud. The frogmouth catfish will only accept live food. Here is a video of one eating some shrimp!
Today features a short post concerning one of the strangest looking groups of catfish—which is truly saying something since the entire order of catfish appears rather odd. Brachyplatystoma is a genus of catfish from central South America which includes the largest catfish from that continent, Brachyplatystoma filamentosum, the so-called Goliath catfish or Piraiba, which is capable of reaching up to 3.6 metres (12 ft) in length and can weigh up to 200 kg (450 pounds). The Piraiba is hunted for food and sport both with hooks and with harpoons. All Brachyplatystoma catfish are swift sleek fish which live by hunting, but whereas the other species mostly hunt fish, the Piraiba has been known to eat primates. Specimens have been found with monkeys in their digestive system and attacks on humans are darkly rumored (although ichthyologists scoff that the mighty fish only scavenges the remains of such terrestrial animals).
The other Brachyplatystoma catfish species are smaller than the giant Brachyplatystoma filamentosum, but they all have the elongated flattened nose which characterizes the genus. One of these species, B. tigrinum, has especially lovely stripes. Although an unusual fish, it is caught in sufficient quantities to be available in specialty stores for home aquariums, where its long nose, pretty stripes, and interesting behavior fetch a premium price.
I wanted to add one final post to my armor posts of last week. Although I posted about chitons, Chinese helmets, glyptodons, gothic armor, and Athena, I left out a post about catfish. Ferrebeekeeper has already featured one post about the armored catfish of the Loricariidae family (an extremely large and diverse family of suckermouth catfish from South America), however there is a second different family of armored catfish, the Callichthyidae, which are characterized by two rows of bony plates (or scutes) running the length of their body. The Callichthyidae are comprised of 9 genera of catfish (and taxonomists will probably discover a few more in the future) including the Corydoras genus, which includes some of the most endearing and popular tropical aquarium fish.
Callichthyidae literally means “beautiful fish” in Greek and the endearing little fish are common in virtually every freshwater habitat throughout South America. Some species of the little armored catfish are able to flourish in stagnant or swampy water by a unique physiological mechanism. The fish gulp air into their intestines where the oxygen permeates into the blood vessels. Through this fake lung they are able to survive conditions which could kill other fish and even travel overland for brief distances (although they do look rather comic expelling the air dorsally in silvery bubbles).
A distinctive (and extremely eponymous!) example of the Callichthyidae is Callichthys callichthys an eight inch drab catfish which ranges from Trinidad to Patagonia—an extremely large range for a little fish. The male of this species is a bubble nester who builds a large nest out of plant parts and bubbles formed from air and mouth secretions. Until he is perfectly satisfied with his construction he chases the female away. Only when his nest is perfect does he let her enter: then both partners work together to defend their offspring within the little floating home.
When I was a child, I kept tropical fish. The first tank I had in my bedroom was an Amazon community tank where angelfish, neons, serpa tetras and hatchetfish lived in a little miniature paradise of plastic swordplants and petrified stone. Among the very first batch of fish I added to this tank were two adorable little masked Corydoras catfish. The Corydoras genus consists of over a hundred and fifty species of small friendly armored catfishes from South America. Corydoras means helmet-skin in Greek because these fish are armored catfish with two rows of bony plates running down their bodies (like the superfamily Loricarioidea). Most of the “cories” are only an inch or two in size.
These fish are popular with hobbyists because they are extremely endearing. They race around the tank in bursts and then root enthusiastically through sand and gravel (burying their bewhiskered snout to the level of their eyes). They like to have other cories for companions. Occasionally they dart to the top of the water for a little sip of air. Like most catfish, their fins have a leading spine for protection. Unfortunately when I got my two cories, one of the two fish freaked out and deployed his spine thereby injuring the other fish’s gills. It was very touching how the catfish which accidentally harmed its friend would hover near the hurt fish nudging him (or her) to eat and to swim up for sips of air. Unfortunately it was no good and there was no way I could help the tiny injured corydoras. After a few sad days, the poor catfish was the first fatality in my tropical tank. Death came quickly to my underwater paradise and would thereafter be a frequent guest. I was very upset. I buried the fish on a big hill in a little tiny cardboard box (according it an honor that few of my other fish ever received). It was the first of my many, many failures as an aquarium keeper, but it provided me with an abiding lesson about fish personality–which is more nuanced, deep, and likeable than most people suppose.