New Species Of Pillbug Discovered Near L.A.

37 New Species Of Pillbug Discovered Near L.A.
The new species found in the port of L.A., Exosphaeroma pentcheffi / Kelsey Vo Bailey CC-BY 4.0

A new species of pillbug has been found, not in some remote pristine marine environment, but less than one mile from the busiest port in the United States. It was discovered whilst students from the Loyola Marymount University were on a college field trip scouring the beaches of the southernmost tip of the city of Los Angeles.  

They found the little critter “clutching on for dear life to one of the five arms of a common sea star,” according to Dean Pentcheff, a researcher from the Natural History Museum of Los Angeles County (NHM), who was leading the students during the outing. “As soon as we saw this bumpy little guy, we knew it was something special that the researchers at NHM had to see, but my class and I had no idea we were looking at a new species.”


The pillbug, known as an isopod, is directly related to the little grey woodlice found in the backyards of most homes. Whilst called bugs, they’re not actually insects at all but are in fact crustaceans. The largest ones grow to a whopping 36 centimeters (14.2 inches) and live in the deep, cold waters of the oceans, whilst the smallest species can be just 0.3 mm in length. The females brood their young in a little pouch just above the stomach.

The newly discovered specimen, which only measured around 5 mm, was handed over to the NHM where world isopod experts Dr. Regina Wetzer and Adam Wall examined it. “Once we got the specimen to the Museum, we knew it was something unusual,” explained Wall, who co-authored the paper published in ZooKeys. The tiny creature was so small that the researchers had to use a scanning electron microscope to get a proper look. 

The second species described, Exosphaeroma paydenae, found in the museum's collection. Credit: Adam Wall et al. 2015

But the discoveries didn't end there, as when trawling through the museum's massive collection of pillbugs in order to compare the new species, the researchers stumbled upon another previously unidentified specimen. Collected over a century ago on a wooden ship in Alaska, it had lain preserved and unrecognized in the museum's collection. “It was really exciting to discover a new species that had just been hiding in a collection room for 142 years, waiting for someone to come along and realize it was a new species,” said Wall.     


The new species discovered by the college students has been named Exosphaeroma pentcheffi, after the teacher who found the first specimen, whilst the Alaskan species is named Exosphaeroma paydenae

“It is amazing to think that you can discover a new species in one of the most urban places in the world like the Port of Los Angeles,” says Wall. “What is even better is that it wasn't an older guy wearing a white lab coat or a marine biologist in SCUBA gear that discovered it. It was a group of college students and their teacher in a regular college class—true citizen scientists.”  

Image in text credit: Adam Wall et al. 2015  


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