Mold pigs! Trapped in amber! 30 million years ago!

Watch out, water bears. You've got some competition in the cute, weird, tiny animal department.

Amanda Kooser
Freelance writer Amanda C. Kooser covers gadgets and tech news with a twist for CNET. When not wallowing in weird gear and iPad apps for cats, she can be found tinkering with her 1956 DeSoto.
Amanda Kooser
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Amber expert George Poinar Jr. refers to this as a "mold pig."

George Poinar Jr.

If you think tardigrades are adorable, then I've got a new critter for you to coo over. Meet the "mold pig," a microinvertebrate that lived 30 million years ago during the mid-Tertiary period, a time when mammals were really starting to strut their stuff.

We know about this delightfully chonky-looking creature because several hundred got themselves trapped in amber. They were later discovered in the Dominican Republic. Amber expert George Poinar Jr. from Oregon State University published a paper on these intriguing creatures in the journal Invertebrate Biology in late September.   

The mold pigs share some characteristics with mites and tardigrades (also known as water bears), but are their own thing. Poinar officially named the invertebrates "Sialomorpha dominicana," with "sialomorpha" derived from the Greek words for "fat hog" and "shape." But you can just call them by their catchier nickname: mold pigs.

"Every now and then we'll find small, fragile, previously unknown fossil invertebrates in specialized habitats," Poinar said in a Monday release from OSU. "And occasionally, as in the present case, a fragment of the original habitat from millions of years ago is preserved too."

Poinar analyzed the amber and found the mold pigs mostly dined on fungi and grew through a molting process where they shed their exoskeletons. 

The mold pigs are mysterious. "We don't know when the Sialomorpha lineage originated, how long it lasted, or whether there are descendants living today," Poinar said. 

Amber is a great equalizer when it comes to small animals. Each piece is like a postcard from the deep past. Some have spiders with freaky tails, some have birds with weirdly long toes, and sometimes you get mold pigs -- pretty much the best microinvertebrate name ever.

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