A species of marine that scientists lost sight of for almost 70 years recently made its comeback when researchers discovered evidence of a certain ocean worm’s existence in images taken by scuba divers. The worms were found coexisting with the seahorses in coral colonies from Australia to Japan, reported CNN.
The long-lost worm is Haplosyllis anthogorgicola, a type of polychaete or bristle worm. It burrows inside branching gorgonian corals at a density of up to 15 worms per cubic centimetre, and its usual size is no more than 0.24 inches (6 millimetres). However, scientists noted in the journal Proceedings of the Royal Society B: Biological Sciences that the animal hasn’t been seen in the wild since 1956, when Huzio Utinomo, a marine biologist from Kyoto University, first identified it.
Chloé Fourreau, lead study author and a doctoral student in the Molecular Invertebrate Systematics and Ecology, or MISE, Laboratory at the University of the Ryukyus in Okinawa, Japan stated that finding these worms is very difficult because of their small size and near transparency, which make them nearly invisible underwater.
When the coral was collected and sent to the lab, the researchers discovered the coral was full of microscopic worms, each less than 0.2 inches long.
Once upon a time my friend and labmate Ai, who studies pygmy seahorses, brought me a worm she found on the coral host of the seahorse…???????? pic.twitter.com/VBf69UPirh
— Chloé Fourreau (@ChaoticChloeia) November 14, 2024
The images were originally taken to study the pygmy seahorses that also live among the coral.