In the abyssal plains of the Gulf of Alaska, precisely at a depth of approximately 3,251 meters (two miles), a golden, softball-sized artifact adhered to a rocky substrate perplexed marine biologists and the general public alike. Queries arose: could it be an egg? A sponge? Or perhaps an enigma of unknown origin? Subsequent scientific investigations spearheaded by the Smithsonian National Museum of Natural History have proposed a far more compelling explanation: the ‘golden orb’ represents the vestigial remains of a seldom-observed anemone species.
This ‘golden orb’ was found at a depth of about 3,300 m in the Gulf of Alaska. Image credit: NOAA Ocean Exploration, Seascape Alaska.
The peculiar ‘golden orb’ was retrieved on August 30, 2023, by the remotely operated vehicle Deep Discoverer, which was deployed from the U.S. research vessel Okeanos Explorer.
Measuring roughly 10 centimeters (4 inches) in diameter, this enigmatic object was discovered amidst a cluster of delicate glass sponges on the seabed southwest of Walker Seamount in the Gulf of Alaska.
Its lustrous, metallic appearance and a distinctive aperture immediately fueled speculation regarding its provenance.
“Our initial macroscopic evaluation indicated that the specimen lacked discernible typical animal structures, such as a mouth, digestive tract, or muscular tissues. Instead, it appeared to comprise a loose agglomeration of fibrous material enveloped by a smooth, stratified exterior,” reported lead author Dr. Steven Auscavitch and his research team.
Subsequent high-magnification microscopic examination revealed that the surface was densely populated with unique stinging organelles characteristic of Hexacorallia, a diverse phylum of cnidarians that encompasses sea anemones and reef-building corals.
Relicanthus daphneae possesses pale purple or pink tentacles that can extend to lengths approaching 2.1 meters (7 feet). Image credit: Craig Smith & Diva Amon, ABYSSLINE Project.
The researchers also meticulously analyzed a comparable specimen recovered in 2021 during an expedition aboard the Schmidt Ocean Institute’s Research Vessel Falkor, identifying similar microscopic stinging structures.
Genetic sequencing corroborated this association: Deoxyribonucleic acid extracted from the ‘golden orb’ exhibited a definitive match with Relicanthus daphneae, a reclusive species of deep-sea anemone distinguished by its substantial size and elongated, flowing tentacles.
Collectively, these findings coalesced to support a surprising deduction: the ‘golden orb’ was not a living entity but rather a biological remnant originating from the base of the anemone.
This specimen represented the basal portion of a Relicanthus daphneae individual, which had been affixed to the rocky substratum.
“The specimen constitutes a novel microhabitat comprising a residual cuticle, originally secreted by Relicanthus daphneae – itself a species rarely encountered and recently cataloged, thriving between depths of 1,200 and 4,000 meters (0.75-2.5 miles) – along with a microbial community residing on and beneath its cuticle and encompassing tissues,” the scientists elaborated.
“These significant discoveries, facilitated by specimen retrieval, would likely not have been realized were it not for the object’s peculiar golden hue and its perplexing, egg-like morphology.”
This Relicanthus daphneae was documented during a 2016 expedition aboard the NOAA Ship Okeanos Explorer in the Mariana Islands region. Image credit: NOAA Ocean Exploration, Deepwater Exploration of the Marianas.
Although infrequently collected, Relicanthus daphneae is presumed to have a worldwide distribution.
Individual polyps can achieve diameters of approximately 30 centimeters (12 inches), further complemented by long, undulating tentacles that may extend to twice that width.
Ecological observations suggest that these organisms affix themselves to rocks or sponges, extending their tentacles into prevailing currents to capture passing sustenance.
It is also conceivable that they traverse the seafloor, potentially leaving behind traces of this same golden cuticle.
The precise rationale for the shedding of this material remains a subject of scientific inquiry. One plausible hypothesis involves a form of asexual reproduction known as pedal laceration.
“Our findings underscore the profound extent to which the biodiversity and organismal biology of obscure deep-sea fauna broadly remain undetermined. They also highlight the indispensable value of comprehensive specimen collections and rigorous taxonomic follow-up in the context of telepresence-enabled oceanographic exploration,” the authors concluded.
Their dissertation was disseminated online on April 21, 2026, via the bioRxiv preprint repository.
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Steven R. Auscavitch et al. The Curious Case of the Golden Orb – Relict of Relicanthus daphneae (Cnidaria, Anthozoa, Hexacorallia), a deep sea anemone. bioRxiv, published online April 21, 2026; doi: 10.64898/2026.04.17.719276
