Monday, May 6, 2013

The Ugliest Fish in the World, by Zach Moran

What classifies a fish as ugly? Is it the morphological characteristics the fish exhibits or its habits of character that define its ugliness? There are nearly 30,000 species of fish, each having been shaped by the forces of evolution and natural selection. These processes have allowed fish to become one of the most dominant polyphyletic groups on this planet, but in some species, it has caused their physiology to take the appearance of ghastly monsters. This essay’s purpose is to focus on a group of some ugly fish, what makes them so gruesome, and what habits they have that earned them the title “The Ugliest Fish in the World”?
 The Wells catfish Silurus glanis is found in many countries of Europe including France, Germany, and Spain. It is a gargantuan creature, reaching lengths of eight feet and nearly three hundred pounds (Brittonn et al. 2007). This beast inhabits warm, murky waters where it can ambush prey that happens to wander by. It has a long body with mottled brown and grey skin. It is powered by an elongated caudle peduncle and fin earning it the title “sheet fish” (Brittonn et al. 2007). Towards the anterior of this giant is a massive head, with a cavernous mouth filled with rows of rasping teeth. This gives the Wells Catfish a torpedo shaped body perfect for swimming in an aquatic environment. Prolific growth rates and insatiable hunger have made this catfish one of the most dominant predators in the habitats it resides. This becomes an issue when The Wells Catfish is introduced outside its native habitat causing the decimation of native populations of fish and aquatic life. 
Wels Catfish    photos from

The Asian Sheepshead Wrasse Semicossyphus reticulatus is a large fish within the family Labridae. It inhabits Pacific waters where it feeds upon other fish species. Unfortunately for the Asian Sheepshead Wrasse, it suffers from severe hyperostosis (McGrouther, 2010). This causes the Asian Sheepshead Wrasse to have grotesque nodule growths on its forehead and chin. These swellings may be due to hormones produced during mating season (McGrouther, 2010). The Asian Sheepshead Wrasse’s mouth is something out of a dentist’s nightmare, with teeth snarled in every direction. This accompanied by such terrible facial features are what earns the Asian Sheepshead Wrasse the term ugly. 
Asian Sheepshead Wrasse   photo from

The Goosefish of the family Lophiidae is a truly terrifying fish with dental hardware out of a horror film. Its mouth and head is nearly two thirds of its entire body allowing this beast to eat anything that will fit down its maw. Everything from baby sharks to seagulls has been found in its distorted belly (Banta, 1941). The Goosefish is propelled by a pair of huge ambulatory pelvic fins that move it slowly across the bottom of the sea floor. The body is covered with loose patches of skin that give this fish the appearance of a dish mop. Perched upon its head is a fleshy appendage that the Goosefish uses to lure in prey. This morphology allows the Goosefish to be perfectly camouflaged on the bottom of the ocean where it lurks, waiting to ambush its next unsuspecting meal.
Goosefish   photo

 The Greenland Shark Somniosus microcephalus is the largest shark in the family Squatinidae. It occupies the frigid waters of the Arctic and North Atlantic ranging as deep as six thousand feet below sea level. The Greenland shark has a long heterocercal tail, blunt rostrum, and like most sharks its body is covered in placoid scales. It is one of the slowest moving fishes on the planet due mostly to the cold water it lives in. Greenland Sharks are notoriously slow swimmers and yet despite this, they are able to prey upon seals. Research has found that the Greenland Sharks eat the seals that are sleeping underwater to avoid polar bears (Watanabe, Lyderson, Fisk & Kovacs, 2012).

Greenland Shark

The wolfish Anarhichus lupus is the monster that made us scared to come out from under our covers at night. It is a huge fish reaching lengths of nearly two and a half meters in length and weights of forty-five kilograms. The most distinguishing feature of the wolffish is its teeth. Large anterior conical canines and massive lateral and palatine molars give this Monstrosity some of the most impressive dental hardware found in the animal kingdom (Helfman, Collette, Facey & Bowen, 2009). Also called the wolf-eel, the wolffish has a body covered in Purple and greenish skin. It lives underneath rocks and shelves of the reefs where it waits to ambush prey.

Wolfish     photo

From the dark abyss of the deep ocean arises the ugly Anglerfish Lophius piscatorius. Its body is a robust balloon with snarled teeth at one end and stumpy caudal fin at the other. Perched upon its head is a bioluminescent lure that is used to capture unsuspecting prey. The anglerfish is capable of swallowing prey nearly twice the size of itself due to its huge mouth and flexible stomach (Preciado, Velasco, Olaso & Landa, 2006). Since it is difficult to find mates, male anglerfish will actually weld themselves onto the female becoming a parasitic pair of testes. It is described by National Geographic as “What may be one of the ugliest animals on the planet”.
Anglerfish    photo

The batfish is a fish of the family Ogcocephalidae. It is quite an ugly fish with the appearance of a dumbstruck staring frog. Underneath its dorso-ventrally flattened body are pelvic and anal fins that have been modified into leg-like structures. The Batfish uses these structures to gently tip toe across the bottom of the ocean without being seen by predators. Batfish males also become parasitic although this trait has evolved separately from anglerfish (Helfman, Collette, Facey & Bowen, 2009). It is unequaled as an opportunistic feeder using its huge mouth to engulf prey bigger than its own head.

Redlipped Batfish   Photo
The lumpfish Cyclopterus lumpus is small fish that inhabits the waters of the Atlantic. Although it is one of the most advanced Scorpaeniformes (Helfman, Collette, Facey & Bowen, 2009), this fish looks like a creature from outer space. Mute colors coat the lumpfish helping it stay camouflaged on the sea floor. Its body is a lump of flesh topped with a head that has the appearance of a brain lying underneath transparent skin. Although very little is known of lumpfish eating habits, there have been reports of them eating jellyfish and amphipod crustaceans (Everman & Jordan, 1896). Offspring also show prolific growth rates. For example, in the laboratory lumpfish can triple in size from three point eight inches to twelve inches in one year (Everman & Jordan, 1896). 
Lumpfish   photo

The hagfish is a member of the order Myxiniformes. With an eel-like body and a cartilaginous backbone, this ancient species of fish has the nasty adaptation of secreting a protein rich mucous from pores in its body. Think of snot on steroids, the mucous is used as a defense mechanism that chokes predators when they try to eat the hagfish (Gouglass, Levy, Chiu & Gosline, 2005). The hagfish is also a scavenger, feeding off of decaying organic matter in the anoxic waters of the Ocean floor. Its feeding habits are particularly nasty, squirming its way inside the body of the corpse and then eating its way out from the inside. 
Hagfish    photo

The Blobfish Psychrotlutes marcidus is found off of the coast of Australia (Binolhan & Ortanez). It is the couch potato of the deep sea as its feeding habits consist of sitting in one spot waiting for food to drift by close enough for it to be eaten. This combined with neutral buoyancy allow the Blobfish to be very energy efficient. Due to the fact that the Blobfish inhabits deep waters (Binolhan & Ortanez) its internal skeleton is gelatinous, consisting nearly entirely of flesh. As a result, when brought to the surface, the Blobfish appears to melt as though it is made of candle wax. Its face is almost human-like with a downturned frown, droopy nose and flabby jowls. The Blobfish is famous for being the ugliest fish in the world. Source after source lists this fish as ugly, morose, depressed, and ghastly in appearance. This is true as the Blobfish wins the ugliest fish in the world title by a landslide!
Blogfish     photo

We are blessed to live in a time of incredible biodiversity. Among this incredible diversity is the extant group known as the fishes. A group so rich in life that nearly every possible morphological shape imaginable has been created over millions of years of evolution. Some groups have been so drastically changed that their appearance can be described as ugly. It is without a doubt that the fishes listed above are indeed ugly. However in a way they are marvelous structures of evolution. So adapted to their environment that they could exist in no other niche on the planet. In conclusion we should revere and respect these fish for being so ugly because this has allowed them to survive while other species have gone extinct.


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Banta, A. (1941). Another avivorious angler or goosefish. (1941). Science Magazine, 93(2407), 158.
Gouglass, F., Levy, N., Chiu, S., & Gosline, J. (2005). Composition, morphology, and mechanics of hagfish slime. (2005). Journal of Experimental Biology,208(24), 4611.
Preciado, I., Velasco, F., Olaso, I., & Landa, J. (2006). Feeding ecology of black anglerfish. (2006). Journal of the Marine Biological Association of the United Kingdom, 86(4), 877.
Watanabe, Y., Lyderson, C., Fisk, A., & Kovacs, K. (2012). The slowest fish:swim speed and tail-beat frequency of Greenland sharks. (2012). Journal of Experimental Marine Biology and Ecology, 426-427(7), 5.
Helfman, G., Collette, B., Facey, D., & Bowen, B. (2009). The diversity of fishes. (2nd ed.). West Sussex: John Wiley & Sons Ltd.
McGrouther, M. (2010, September 03). Asian sheepshead wrasse. Retrieved from
Everman. , & Jordan, (1896). Lumpfish. (1896). The Lumpfishes: Family Cyclopteridae, (2096), 459. Retrieved from
Binolhan, C., & Ortanez, A. (n.d.). Psychrotlutes marcinus: The blobfish. Retrieved from

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