Researchers have recently described four new species of deep-sea scale worms with beautiful iridescent scales and sparkly bristle-like hairs. Nicknamed ‘glitter worms’ these new species are not just visually stunning but also extremely interesting.
On land worms are arguably one of the most simple and un-interesting animals you can find, but under the waves their deep sea cousins can dazzle and amaze us with vivid colours and fascinating behaviours. Something recently made clear by the discovery of four new species of deep-sea scale worms, scientifically known as Peinaleopolynoe, by researchers from America and France. Due to their vibrantly colourful scales and glittery bristles these new specimens have been nicknamed the ‘glitter worms’, with one species even being named after famous rock & roll musician and sequin lover Elvis Presley. However despite their beautiful appearance, these iridescent scales are likely to play a much more crucial role than just looking good, as well as aiding in some truly bizarre behaviour.
Deep sea discovery
The new species of glitter worms were described by a team of researchers from the Scripps Institution of Oceanography, at the University of California, and Paris-Sorbonne University. They published their findings in a recent paper in the journal ZooKeys last month. The specimens used to identify the new species were collected at 3,700m depth at the Pescardo Basin in the Gulf of California. The new species include Peinaleopolynoe goffrediae, P. mineoi, P. orphanage & P. elvisi (named after rock & roll legend Elvis Presely). They are all deep-sea scale worms, distant relatives of terrestrial earthworms, with overlapping scales that give them their names.
The most striking thing about these newly discovered worms is obviously their iridescent scales and vibrantly colourful bristles which make them so visibly stunning. Normally these types of colourful decorations would play a role in attracting a mate or as a warning for predators over their toxic properties. However at depths of greater than 1000m it is unlikely that any animals, including scale worms (who have no defined eyes), can actually see these beautiful scales at all. This has led many scientists to believe that the iridescence of glitter worms has no functional significance at all. Instead the researchers believe that the scales themselves are what is important and not their colour. They suspect that their main purpose is to provide protection to the worms from attacks by other worms, as illustrated by the damage to some shells on the collected specimens.
So rather than using their colourful scales to attract other worms, the most likely scenario is that they are actually to protect them from rivals instead. Little is known about what causes this infighting between worms, but it is most likely to be competition over limited resources in the deep (i.e. food, mates or territory). However thanks to video captured by researchers we now know what it looks like. The clip (seen below), which was first shared online last year by one of the paper’s author Greg Rouse, shows an encounter between two glitter worms surrounding a hydrothermal vents. The encounter is sped up 4x in the video to make it more interesting, but regardless it still highlights a very strangely choreographed fight between two worms that seem to be both sizing each other up and trying to land the odd bite.
Whatever the bizarre behaviour shown in the video is really for is still unknown, but from what we know about these new worms it is likely that it they are not fighting over food. That is because these colourful critters are actually seafloor scavengers. In fact three out of the four new species were discovered feeding on a decaying whale carcass, commonly known as a whale fall. It therefore seems likely that this is one of their main sources of food and because the whales are so big, and shared between so many different scavengers like octopus and sea stars, there is plenty to go around and nothing to fight over. So whatever their strange stand-offs are really about remains a mystery and highlights how little we still know about the deep ocean.