One species of clam has returned from the dead.
It is also known as Cymatioa cookiThe clam was only found as a fossil and scientists assumed that the species had been extinct for over 400.000 years. When Jeff Goddard was looking for sea snails off California’s coast in 2018, he noticed something unusual: A translucent, white bivalve measuring 11 millimeters long.
Goddard of University of California Santa Barbara photographed the clam to avoid disturbing it. He also shared the images with another colleague. Paul Valentich-Scott, curator of malacology at the Santa Barbara Museum of Natural History, didn’t recognize the marine critter either, which made him happy. “New discoveries are part of why we’re in science,” Valentich-Scott says.
In 2019, the pair captured a live specimen and returned it to the museum to examine its similarities with other fossil species. It bore striking similarities to a fossil bivalve that George Willett, a paleontologist, first described in 1930s.
Willett named it after Edna Cook, an amateur collector of shells who noticed the fossil as unique among her collection of over 30,000.
“Once I physically saw that original specimen that Willett had used for his description, I knew right away” that the live clam was the same species, Valentich-Scott says.
Scientists are still puzzled over why the critters have evaded science for so long. One theory is that C. cooki’s preferred habitat is farther south in Baja, Calif., perhaps in a remote area. A mass of warm waters may have washed some larvae towards Santa Barbara. Goddard and Valentich Scott have so far found at most two, but possibly four of these clams.
“It’s rare to find something first as a fossil and then living,” says David Jablonski, a paleontologist at the University of Chicago who was not involved in the research.
The triumphant reappearance This is C. Cookie, described November 7 in ZooKeysThe clam is placed amongst a group believed to be back-from the-dead creatures, dubbed Taxa Lazarus (SN: 11/13/07). Even with the vast array of animal specimens available to modern scientists, Jablonski says, “there’s always more to find.”
