A marine biologist at UC Santa Barbara has discovered four new species of sponge in the kelp forests off Southern California.
The novel specimens weren’t dredged from the murky depths or found on some distant seamount, but collected locally from popular dive spots.
Associate Professor Thomas Turner collected hundreds of samples by hand from dives he conducted all around Southern California, then sequenced their genes to determine their species.
The four species described in a new paper in the journal Zootaxa appear as nondescript beige patches on kelp forest rocks.
“When I got the DNA, I was shocked to learn that they were in Scopolinida, which is almost entirely tropical,” he said. Species in this order of the sponge family were unknown on the West Coast.
“They live out in the open; divers have been swimming past them for decades,” Turner said. “They’re all over Southern California, super common. Just no scientist has ever picked one up and looked at it to try to figure out what it was.”
In 2020, Turner discovered another new species of sponge, which he named Galaxia gaviotensis, in waters off Santa Barbara.
Sponges diverged from all other animals over 600 million years ago, with the major subgroups parting ways not long after that. “So, the amount of independent evolution within sponges is comparable to that within all other animals,” explained Turner.
Because they diverged from other animals so long ago, they can potentially tell scientists a lot about life’s evolution.