Are colossal squid real? Specimens, images and evidence

A species established before it was filmed alive

Mesonychoteuthis hamiltoni, the colossal squid, is supported by physical remains and museum specimens. Evidence from remains recovered from predators helped establish the species long before modern ROV video. The name dates to formal naming in 1925; Te Papa’s preserved specimen was caught in the Ross Sea in February 2007 by the vessel San Aspiring. [1] [2]

That chronology distinguishes existence from direct observation. A specimen can establish anatomy through inspectable physical material even when no camera has recorded a living animal in its habitat. A verified video adds evidence of movement and appearance in context, but it does not replace the specimen record. [2]

What the 2025 footage confirms

On March 9, 2025, ROV SuBastian filmed a transparent juvenile near the South Sandwich Islands at 600 metres. It was about 30 centimetres long. Independent squid specialists checked the footage, with hooks along the middle of its arms serving as a key diagnostic feature. [3]

The footage was announced on April 15, 2025, and described as the first confirmed footage of a colossal squid alive in its natural deep habitat. That is a claim about confirmed live footage, not first discovery, first evidence of existence or the first physical specimen. [3]

Read hooks, body form and life stage together

The squid belongs to Cranchiidae, the glass-squid family. Diagnostic hooks on the arms and tentacles help distinguish it, and museum collections provide material for anatomical inspection. In footage, specialists used the hooks along the arm middles to support identification. A visual resemblance alone is weaker evidence than a diagnostic feature reviewed by specialists. [2] [3]

The filmed animal’s transparency and small size differ strikingly from the massive, opaque adults familiar from specimens. This is not a contradiction: the images and specimens represent different life stages and forms. As a clearly hypothetical evidence exercise, compare a 30-centimetre transparent animal in video with a large preserved female. Their appearances might seem unrelated until a diagnostic feature such as arm hooks and specialist review connect the evidence. [3] [2]

What a juvenile cannot establish about adults

Schmidt reports adult mass estimates up to approximately 500 kilograms. That estimate concerns adults, not the juvenile filmed at 600 metres; the young animal’s observation does not establish adult size, mass or ecology. Maximum dimensions remain constrained by the small number of large specimens, so an upper estimate should not be treated as routine adult size. [3]

A specimen, prey remains and an ROV observation answer different questions. Physical material permits anatomical study; predator remains can preserve evidence of an otherwise rarely encountered squid; a video shows an animal alive at a particular moment and site. A single juvenile observation cannot establish adult behavior, habitat use or the species’ full life cycle. [2] [3]

Colossal squid and giant squid are different taxa. Footage or behavior attributed to Architeuthis cannot be used as evidence for Mesonychoteuthis. Keeping the names and evidence types separate is necessary when assessing claims about these elusive animals. [3]