New species of fish described as a ‘living fossil’ found in deep waters off Bermuda
Scientists have discovered a new species of fish – described as a “living fossil” – in the deep waters off Bermuda.
Polymixia hollisterea – a species of spiny-rayed beardfish – was named in honour of Gloria Hollister, a pioneering female marine biologist involved in the record-setting bathysphere dives off Bermuda in the 1930s.
While the species does not have a common name, it has been proposed that it is known as the Bermuda beardfish.
According to the winter edition of the Department of Environment and Natural Resource’s Envirotalk newsletter, the new species was caught in 1997 by Craig Soares and Richard Allen.
Two of the unusual fish were caught on a deep line off Easter Blue Cut in 1,600ft of water and were donated to the Bermuda Aquarium Museum and Zoo, where they were preserved.
The fish were initially identified as another species, the more common Polymixia lowei, but careful reassessment of the bones in the fin structures and new genetic data have revealed them to be a different species.
The only other known specimen of Polymixia hollisterea was found in the north central section of the Gulf of Mexico.
Researchers Terry Grande and Mark Wilson of Loyola University Chicago, formally published a description of the new species in the scientific journal Ichthyology & Herpetology.
Dr Grande and Dr Wilson both came to the island in 2018 to study the fish and their findings were recently published.
Polymixia are known commonly as beardfish because of their barbels – whisker-like sensors that come out of their lower jaw used to find food in murky waters.
Several Polymixia lowei have been caught on the deep slope off South Shore, along with a single Polymixia nobilis, which was found off Challenger Bank by Bobby Doe in 1973.
Robbie Smith, curator of the National History Museum, said: “Species of Polymixia have been called ‘living fossils’ because of their unusual retention of primitive features, and because Polymixia is the last survivor of a Cretaceous radiation of polymixiiform fishes, over 65 million years ago.
“There are only ten species of Polymixia known globally, so it is remarkable we have three here.”
Dr Smith added that the decision to name the new species after Gloria Hollister was a fitting tribute to the groundbreaking researcher.
He said: “She was a key member of William Beebe’s Bathysphere Expeditions on Nonsuch Island in the 1930s, which set world records for deep-sea descent and biological observations off Bermuda.
“Gloria set a record herself for deepest descent by a woman, which stood for decades.
“Hollister also described new species of fishes and she perfected a method for clearing fish specimens and staining their bones, allowing study of the skeleton through transparent flesh – a method still widely used with slight modification today.”
Ms Hollister, who died in 1988, also worked with William Beebe exploring tropical jungles in Guyana, did pioneering work for the Red Cross Blood Bank during the Second World War and was an advocate for land conservation.