Giant invertebrates (sea serpent type)

This article is about the sea serpent type. For general giant invertebrates, see the category invertebrates or the page invertebrates in cryptozoology.

"Marvin the Monster," an unidentified, serpentine marine invertebrate photographed by the ROV Mobot off the Pacific coast of the United States.

Giant invertebrates are a Heuvelmans type of sea serpent, a wastebin category containing reports of giant, elongate tunicates and ctenophores, expanded to include cnidarians and ribbon worms by Michael Woodley. This type is also present, under the same name, in the Marshall system. Based on a theory propounded by Roy P. Mackal after the publication of Bernard Heuvelmans' In the Wake of the Sea-Serpents (1968), giant invertebrates have not received as much attention as the other Heuvelmans types, and have no equivalent in the other main classification systems. It is unclear if Bernard Heuvelmans intended the category to contain only new species, or oversized specimens of known species.

Mackal reinterpreted the yellow belly as a salp↗ chain and thus a synonym for this type, and, while the many-finned sea serpent has also been reinterpreted as a giant invertebrate, it does not fit the type's profile. Dale A. Drinnon has identified another category of cryptid marine invertebrates, unknown invertebrates, which includes the arthropod kajanok, as well as a distinct giant jellyfish category.

List of sightings

• Table Bay (South Africa, 1857)
• Mobot (U.S. Oregon, 1963)
• Sandy Hook Marine Laboratory (U.S. New Jersey, 1963)
• George Hale (Gulf of Mexico, ~1970s)

Significant sightings

Sandy Hook (1963)

A very long, transparent sea creature identified as a marine invertebrate was observed by several biologists and divers of the vessel Challenger during a research dive off New Jersey's Sandy Hook Marine Laboratory, in a heavily-polluted yet biodiverse area called the "mud pit," on 18 July 1963. Under the direction of Lionel Walford (1905 – 1979), two divers were being lowered into the water in a shark cage, when one of them, Robert Wicklund, saw what he later described as a 40 ft (12 m) long serpentine animal, 5 in (12 cm) "thick" and 7–8 (17–20 cm) in wide. Walford, who almost missed it because it was transparent, compared it to a sea serpent, but stated that "it is an invertebrate." He later decided that it had been a giant Venus girdle (Cestum veneris), far larger than any recorded specimen.

Marine biologist John Clark made a cruise around the "mud pit" the following month, and reported seeing what he identified as a 40 ft (12 m) salp chain, which he believed was the animal originally reported. A Belmar fisherman named Elmer Tiger also later reported seeing a 30–40 ft (9–12 m) long, transparent animal in the sea south of Sandy Hook. However, Walford later told Gardner Soule that the animal had been a very large oarfish (Regalecus glesne), which are serpentine and covered in silvery scales, an explanation accepted by several secondary sources.

Mobot (Santa Barbara, 1962)

The underwater robot Mobot, designed by Shell Oil Company to scan the seafloor for oil deposits, filmed an invertebrate "sea serpent," nicknamed Marvin, off Santa Barbara in February 1961 or 1962. Photographer Forrest Adrian and drilling foreman Paul Martin, watching the footage live from the drilling ship Eureka, estimated that the creature was 15 ft (4 m) in length, but only 6 in (15 cm) in diameter, and described it as moving with a distinctive corkscrew or spiral motion. It remained in view for more than an hour. Adrian was recording the live feed during the animal's appearance, and stills from the footage show that it was "wound about by ridges." Thought to have been a colonial organism, Marvin was variably speculated by Los Angeles marine biologists to be a salp chain, a ctenophore, or a siphonophore, but identification was not possible based on the footage, and it remains unclassified.

Gulf of Mexico (~1970s)

An anonymous user, later interviewed by Chad Arment, claimed on an early online newsgroup that a friend of his named George Hale, working in the Gulf of Mexico during the 1970s, reportedly often saw strange giant invertebrates, including "giant headless glowing living firehoses," as well as an undescribed predator which fed on the "firehoses".

“

I used to have a friend who was at one time an undersea welder for Gulf Oil in the 70's and did work on the oil rigs way out in the Gulf of Mexico. He gave it up because he was seeing things down there that were beyond his ability to comprehend and even describe. And he wasn't the only one. At one oil rig, the welding crew were getting used to seeing this 'giant headless glowing living firehose' that would zoom in from out of nowhere at incredible Nascar speeds and would keep on zooming past the welders for up to fifteen minutes!

”