NOAA Identifies Mysterious 'Golden Orb' as Deep-Sea Anemone Remnant

In August 2023, during an expedition in the Gulf of Alaska, NOAA's remotely operated vehicle Deep Discoverer encountered a peculiar, golden, dome-shaped object adhered to a rock at a depth of approximately 3,300 meters. The object, measuring about 10 centimeters in diameter, featured a small hole near its base, prompting initial speculation that it might be an egg casing, a dead sea sponge, or an unidentified type of coral.

The specimen was collected and sent to the Smithsonian National Museum of Natural History for further examination. Despite extensive analysis, including morphological studies and initial DNA barcoding, the object's identity remained elusive. Allen Collins, director of NOAA Fisheries' National Systematics Laboratory, noted, "This turned into a special case that required focused efforts and expertise of several different individuals. This was a complex mystery that required morphological, genetic, deep-sea and bioinformatics expertise to solve."

Subsequent whole-genome sequencing revealed that the specimen was genetically almost identical to Relicanthus daphneae, a giant deep-sea anemone. Further analysis determined that the 'golden orb' was a remnant of the dead cells forming the base of this anemone, specifically the part that attaches to the rock substrate.

William Mowitt, acting director of NOAA Ocean Exploration, emphasized the significance of such discoveries, stating, "So often in deep ocean exploration, we find these captivating mysteries, like the 'golden orb.' With advanced techniques like DNA sequencing, we are able to solve more and more of them."

The identification of the 'golden orb' underscores the complexities of deep-sea ecosystems and highlights the importance of continued exploration to enhance our understanding of the ocean's mysteries.