Largest sea urchin
Last updated: April 7, 2019 at 17:04 pm
Sperosoma giganteum — Test diameter of 38 cm (15 in) (Test: Urchin body without spines). Diadema setosum has a smaller test (10 cm / 4 in) but its spines are the longest measuring more than 30 cm (12 in).
Gilpin, D. (2006). Echinoderms - Starfish, Urchins, and Other Echinoderms. p. 41.
Please note that comments are moderated: (1) Stay on topic (2) Be respectful (3) Refrain from vulgarity and abusive language (4) Do not make personal complaints about a person’s character, business, work or associations (5) Do not publish materials that violate copyright. OFFENDING COMMENTS WILL BE DELETED.
If you have claim to a diving or underwater record or first, if you know of a significant first or record not listed here, or if you can demonstrate that any of the information on this website is false or outdated, please complete the form on the record submission page.
In order to ensure your browsing experience is as enjoyable as possible, banners are kept to an absolute minimum, which means that advertising revenues alone cannot sustain this 100% FREE publication. Researching and updating the Diving Almanac requires a lot of time and dedication. If you believe the diving community needs a central body of information to record, validate and make available our shared history and accomplishments, please show your support by making a contribution to the Diving Almanac via PayPal (Porbeagle Press). Thank you!
First to dive the Five Deeps
By Jeffrey Gallant
Victor Vescovo was the first human to dive to the deepest point in each of the Earth's oceans using the deep submergence vehicle [...]
Read More
Deepest submersible dive (Solo | Men)
By Jeffrey Gallant
10,925 m (35,843 ft) — Victor Vescovo (USA) aboard the DSV Limiting Factor (Triton 36000/2 model submersible) | Five Deeps Expedition, April 28, 2019 [...]
Read More
Deepest fish (Observed)
By Jeffrey Gallant
The Swire's snailfish (Pseudoliparis swirei) was captured on video at the depth of 8,178 m (26,831 ft) in 2017. This species, more commonly referred to as the Mariana snailfish [...]
Read More
Deepest diving submersible (In service)
By Jeffrey Gallant
The DSV Limiting Factor dived four times to the bottom of the Challenger Deep in April-May 2019, including the deepest dive ever made by a submersible [...]
Read More
Deepest dive by a head of state
By Jeffrey Gallant
5,109 m (16,762 ft) — HSH Prince Albert II accompanied Victor Vescovo to the deepest point of the Mediterranean Sea, the Calypso Deep, on [...]
Read More
Deepest watch (Prototype)
By Jeffrey Gallant
10,925 m (35,843 ft) — Omega Seamaster Planet Ocean Ultra Deep Professional. Two of the Omega timepieces were strapped to the manipulator [...]
Read More
Deepest point in Earth’s oceans
By Jeffrey Gallant
10,994 m (36,070 ft) — The Challenger Deep, located in the Mariana Trench, 250 miles (400 km) southwest of Guam in the Pacific Ocean, is the deepest [...]
Read More
Deepest submersible dive (Ocean)
By Jeffrey Gallant
10,925 m (35,843 ft) — Victor Vescovo (USA) aboard the DSV Limiting Factor (Triton 36000/2 model submersible) | April 28, 2019 | Challenger Deep [...]
Read More
Oldest diver (Men)
By Jeffrey Gallant
99 — William Lambert (USA) celebrated his 99th anniversary with a birthday dive in Pearl Lake, Illinois, on September 5, 2019. He remained at the depth of 9.7 m (32 ft) for 20 minutes [...]
Read More
Fastest drift dive
By Jeffrey Gallant
17.68 knots (32.74 km/h / 20.34 mph) — Sechelt Rapids (Skookumchuck Narrows), British Columbia, Canada. It is estimated that for a 3.6 m (12 ft) tide, 757 billion litres of seawater flow [...]
Read More
Largest jellyfish
By Jeffrey Gallant
Lion’s mane jellyfish (Cyanea capillata) — The largest individuals have a bell diameter of 2.3 m (7.5 ft) with over 800 tentacles; some reaching lengths of 37 m (120 ft). Despite its [...]
Read More
Deepest octopus
By Jeffrey Gallant
Dumbo octopus (Grimpoteuthis) — 6957 m (22,825 ft), Java Trench (Indian Ocean). The octopus was remotely observed using an autonomous baited camera and trap lander in [...]
Read More
First documented case of hydrogen psychosis
By Jeffrey Gallant
Capt Steve Zissou suffered from the debilitating effects of Crazy Eye after witnessing the demise of his diving companion and partner, Esteban du Plantier [...]
Read More
Clearest water
By Jeffrey Gallant
80 m (262 ft) or the approximate visibility of distilled water. A few locations are claimed to equal the visibility of distilled water, including the Weddell Sea (Antarctica), New Zealand’s [...]
Read More
First underwater colony
By Jeffrey Gallant
1963 — Conshelf II (France). Seven divers lived underwater off Sha’ab Rumi (Sudan) in the Red Sea for one month under the supervision of Jacques-Yves Cousteau. The colony [...]
Read More
Most fin patents
By Jeffrey Gallant
Bob Evans (USA) — Since 1971, he has patented 33 revolutionary fin designs including the Force Fin Tan Delta (polyurethane) which is part of the permanent collections of the New York [...]
Read More
Largest glacier calving ever filmed
By Jeffrey Gallant
The largest glacier calving event ever recorded took place on May 28, 2008, when Adam LeWinter and Director Jeff Orlowski were filming the Ilulissat Glacier [...]
Read More
First aquanaut (Men)
By Jeffrey Gallant
1962 — Robert Sténuit | Man-in-the-Sea I project by Edwin A. Link. Sténuit spent 24 hours and 15 minutes in a submersible decompression chamber (SDC) at a depth of 61 m (200 ft) [...]
Read More
Longest migration (Shark)
By Jeffrey Gallant
20,142 km (12,516 miles) — A whale shark (Rinchodon typus) was tracked by satellite from Panama to the Mariana Trench between April 2012 and [...]
Read More
Oldest active scuba club
By Jeffrey Gallant
1938 — Göteborgs Amatördykarklubb (Gothenburg Amateur Diving Club). The club, which was founded on October 22, 1938, began its activities after receiving two Le Prieur [...]
Read More
Jeffrey Gallant is the Editor-in-Chief and Records Keeper of the Diving Almanac. He is also a contributing editor of DIVER Magazine, and the scientific director of the Greenland Shark and Elasmobranch Education and Research Group (GEERG). Jeffrey started diving in 1982.
