Bathyscaphe Trieste
On 23 January 1960, she reached the ocean floor in the Challenger Deep (the deepest southern part of the Mariana Trench), carrying Jacques Piccard and Don Walsh. This was the first time a vessel, manned or unmanned, had reached the deepest known point of the Earth's oceans. The onboard systems indicated a depth of , although this was revised later to ; fairly recently, more accurate measurements have found Challenger Deep to be between and deep.
Pseudoliparis amblystomopsis
In October 2008, a team from British and Japanese institutes discovered a shoal of "Pseudoliparis amblystomopsis" at a depth of about in the Japan Trench. These were, at the time, the deepest living fish ever recorded on film. The record was surpassed by a type of snailfish filmed at a depth of in December 2014, and extended in May 2017 when another snailfish was filmed at a depth of . This deepest-water so-called "ethereal snailfish" remain undescribed, but a close relative found only slightly shallower in the Mariana Trench was described as "Pseudoliparis swirei" in late 2017.