Polymixia lowei
Polymixia lowei, commonly known as the beardfish or Barbudo, is a small species of fish belonging to the Polymixiidae family, which contains only one genus, Polymixia. This species can reach a length of approximately 11.5 inches (29 centimeters) and is characterized by its metallic blue body with a silvery belly and blueish-grey, blunt head. Notable features include long hyoid barbels at the corners of its mouth, a long dorsal fin, and black-tipped dorsal and caudal fins. Polymixia lowei primarily inhabits the deep waters of the Atlantic Ocean, ranging from the coast of New York to the Gulf of Mexico and extending to French Guinea, typically dwelling at depths between 490 and 1,970 feet (150 to 600 meters).
As carnivores, they feed on various marine prey such as crustaceans, shrimp, crabs, octopus, squid, and cuttlefish. Their swimming mechanism involves a coordinated movement of fins, providing stability and propulsion. While their respiratory system functions similarly to other fish, filtering oxygen from water through their gills, little is known about their lifespan. The unique adaptations and characteristics of Polymixia lowei make it a fascinating subject for those interested in marine biology and deep-sea ecosystems.
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Polymixia lowei
Polymixia lowei, also called Barbudo or beardfish, are one of the 10 fish species in the beardfish family Polymixiidae, which has only one genus, Polymixia. These small fish live deep in the Indian, Pacific, and Atlantic Oceans.
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Polymixiiformes
Family: Polymixidae
Genus: Polymixia
Species: Lowei
Polymixia lowei grows to about 11 1/2 inches (29 centimeters) long. Their bodies are metallic, or like-metal, blue with silvery bellies. Their round, blunt heads are blueish-grey. Like other beard fish, they have a pair of long barbels, or whiskers, hanging from the corners of their mouths, called hyoid barbels. Their nose is longer than their upper jaw. Beardfish also have black tips to their dorsal, or back, and caudal, or tail, fins. Like other beard fish, Polymixia lowei each have a long dorsal fin that runs along the length of its back with five dorsal spines and 26 to 32 soft dorsal rays.
Polymixia lowei are bottom-dwelling creatures inhabiting the Atlantic Ocean from the coast of New York to the Gulf of Mexico and as far south as French Guinea. They occupy depths of 165 to 1,970 feet (50 to 600 meters) but usually live between 490 to 1,970 feet (150 to 600 meters) deep. They are carnivores or meat-eating. They eat crustaceans, shrimp, crab, octopus, squid, and cuttlefish.
Polymixia lowei swim using their fins. They balance by the steady positioning of their dorsal and anal, or back and belly, fins, while their caudal, or tail, fins swish from side to side propelling them through the water.
Like other fish, Polymixia lowei get the oxygen they need from the water in which they live. They take water into their mouths, keep the oxygen in that water, and then filter out the chemical wastes through the gills on the sides of their bodies.
Nothing is known of the life span of Polymixia lowei.
Bibliography
"Fish Identification: Find Species." Fish Base, fishbase.mnhn.fr/identification/SpeciesList.php?genus=Polymixia. Accessed 15 Apr. 2024.
"Polymixia Lowei Günther, 1859." Fish Base, fishbase.mnhn.fr/summary/Polymixia-lowei.html. Accessed 15 Apr. 2024.
"Species: Polymixia Lowei, Beardfish." Smithsonian Tropical Research Center, biogeodb.stri.si.edu/caribbean/en/thefishes/species/3055. Accessed 15 Apr. 2024.