Within the lightless depths of the Gulf of Alaska, roughly 3,251 m (two miles) under the floor, a softball-sized golden object clinging to a rock left marine scientists and most people equally baffled. Was it an egg? A sponge? One thing altogether unknown? New analysis led by the Smithsonian Nationwide Museum of Pure Historical past suggests a much more intriguing reply: the ‘golden orb’ is the stays of a not often seen species of anemone.
This ‘golden orb’ was discovered at a depth of about 3,300 m within the Gulf of Alaska. Picture credit score: NOAA Ocean Exploration, Seascape Alaska.
The ‘golden orb’ was collected on August 30, 2023, by the remotely operated automobile Deep Discoverer, launched from the U.S. exploration vessel Okeanos Explorer.
Round 10 cm (4 inches) throughout, the mysterious object was discovered amongst small glass sponges on the seafloor southwest of Walker Seamount within the Gulf of Alaska.
Its clean, metallic sheen and torn opening shortly sparked hypothesis about its origin.
“Preliminary examination of the gross morphology revealed the specimen to haven’t any indication of typical animal anatomy (mouth, intestine, muscle tissues, and many others.), however fairly to encompass a free aggregation of fibrous materials lined by a clean, layered floor,” stated research first writer Dr. Steven Auscavitch and colleagues.
Additional examination beneath mild microscopy revealed that the floor was filled with specialised stinging buildings distinctive to Hexacorallia, a bunch of cnidarians that features sea anemones and stony corals.
Relicanthus daphneae has pale purple or pink tentacles that may lengthen nearly 2.1 m (7 toes) lengthy. Picture credit score: Craig Smith & Diva Amon, ABYSSLINE Venture.
The researchers additionally examined the same specimen collected in 2021 throughout an expedition on Schmidt Ocean Institute’s Analysis Vessel Falkor and located comparable stinging buildings.
Genetic evaluation confirmed the connection: DNA recovered from the ‘golden orb’ matched Relicanthus daphneae, an enigmatic deep-sea anemone species recognized for its massive measurement and lengthy, flowing tentacles.
Collectively, the proof pointed to a stunning conclusion: the ‘golden orb’ was not a residing organism however a organic remnant that shaped on the base of the anemone.
The specimen was the a part of a Relicanthus daphneae person who connected to the rock substrate.
“The specimen represents a novel microhabitat consisting of a remnant cuticle initially secreted by Relicanthus daphneae, itself a not often encountered and just lately described species, which happens between 1,200 and 4,000 m (0.75-2.5 miles), and microbial group residing on and beneath its cuticle and tissue,” the scientists stated.
“These important discoveries enabled by assortment would have been unlikely have been it not for its uncommon golden shade and the specimen’s mysterious egg-like look.”
This Relicanthus daphneae was noticed throughout a 2016 expedition on NOAA Ship Okeanos Explorer within the Mariana Islands area. Picture credit score: NOAA Ocean Exploration, Deepwater Exploration of the Marianas.
Although seldom collected, Relicanthus daphneae is considered globally distributed.
Particular person polyps can attain about 30 cm (12 inches) throughout, with lengthy, sinuous tentacles which will stretch twice that width.
Observations counsel the animals perch on rocks or sponges, extending their tentacles into passing currents to seize prey.
They might additionally transfer throughout the seafloor, probably abandoning trails of the identical golden cuticle.
Precisely why they shed this materials stays unsure. One chance is a type of asexual copy referred to as pedal laceration.
“Our findings underscore the extent to which the biodiversity and organismal biology of obscure deep sea fauna broadly stay unresolved and spotlight the worth of whole-specimen collections and rigorous taxonomic follow-up in telepresence-enabled ocean exploration,” the authors concluded.
Their paper was revealed on-line April 21, 2026 on the bioRxiv preprint server.
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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, revealed on-line April 21, 2026; doi: 10.64898/2026.04.17.719276
