"The deep sea remains as Earth's last frontier, and this study provides a sneak-peek into the least known communities of the Galapagos Islands," said CDF marine scientist Pelayo Salinas de Leon, who led the study and announced its findings.
The expedition explored, for the first time, three steep-sided underwater mountains, or seamounts, located near the islands of Darwin and Wolf in the archipelago's north. The area is home to the world's largest shark population.
"These pristine seamounts are within the Galapagos Marine Reserve and are protected from destructive human practices, such as fishing with bottom trawls or deep-sea mining, that are known to have catastrophic impacts upon fragile communities. Now, it is our responsibility to make sure they remain pristine for the generations to come," Salinas de Leon said.
"The many discoveries made on this expedition showcase the importance of deep-sea exploration to developing an understanding of our oceans," said Nicole Raineault, chief scientist of the Ocean Exploration Trust.
"Since we never know what we're going to find, we utilise land-based scientists who watch the ROV dives from home and communicate directly with the shipboard team in real-time, to help determine what is truly new and worthy of further investigation or sampling.
"Scientists studying the resulting video, data, and specimens make an astonishing number of discoveries, reminding us how little we know about the deep sea," said Raineault.
The Galapagos archipelago, located 1,000km (620 miles) west of Ecuador, is a fragile ecosystem that harbours the largest number of different animal species on the planet.
The news came after Ecuador raised concerns about the presence of a massive Chinese fishing fleeting near the protected waters surrounding the islands.
In recent weeks, Ecuador's navy conducted a patrol mission that included a flyover of the region where the vessels are fishing, as well as reconnaissance by military patrol ships.
A total of 340 ships were reportedly spotted in the area, the navy said, compared with some 260 reported last month.
Ecuador's navy commander, Rear Admiral Darwin Jarrin, said the navy had approached Colombia and Peru to share information and seek a regional response to the vessels, most of which can hold up to 1,000 tonnes of catch.
Ecuador and China have begun negotiations about the fishing fleet, according to reports.
Yolanda Kakabadse, Ecuador's former minister of the environment, told Public Radio International that the Galapagos should be "the last place on Earth to be affected by irresponsible actions of any sort".